Retro1.org codex

DBOOT02 
* /---   FILE TYPE = E
* /---   BLOCK      TITLE      00 000   82/09/03  08.05 
*         IDENT  FDCBOOT,ORIGIN 
         IDENT  FDCBOOT 
*         ABS 
*ORIGIN   EQU    4000H
*         ORG    ORIGIN 
         TITLE  COMMON DISK BOOT LOADER 
* 
* 
* 
*        COMMON DISK BOOT LOADER
* 
*         (C) COPYRIGHT 1982 'CONTROL 'DATA 'CORPORATION
* 
***** 
* 
*        FLEXIBLE DISK LOAD ROUTINE FOR VIKING X, IST2, 
*        AND IST3 TERMINALS.
* 
*        VERSION        00
* 
*        PROGRAMMER      T. E. LARSON 
* 
*        'THIS LOADER IS STORED ON THE FLEXIBLE DISK AND
*        LOADED INTO THE TERMINAL MEMORY AT 4000 HEX BY A 
*        LOAD ROUTINE THAT IS RESIDENT IN THE TERMINAL ROM. 
* 
*        'THE PURPOSE OF THIS LOADER IS TO LOAD THE TERMINAL
*        RESIDENT FROM THE DISK AND PASS CONTROL TO IT. 
* 
*        'DATA FROM THE FLEXIBLE DISK CONTROLLER IS LOADED
*        INTO THE TERMINAL MEMORY BY SECTORS. 'AS EACH
*        SECTOR IS STORED, IT IS CHECKSUMED AND VERIFIED
*        USING THE SECTOR CHECKSUM FROM THE DISK CONTROLLER.
*        'IF THE SECTOR CHECKSUM IS NOT CORRECT, THE
*        LOADER WILL TRY TO RE-READ BLOCK OF DATA FROM THE
*        DISK THREE TIMES  BEFORE ABORTING AND WILL THEN
*        DISPLAY AN ERROR MESSAGE.
* 
* 
**
* 
*        FILE NUMBERS OF DISK RECORDS  (OLD)
*          3    IST2 RESIDENT 
*          4    IST2/3 INTERPRETER
*          5    IST3 RESIDENT 
*          6    IST3 ASCII RESIDENT (THE VIKING RESIDENT) 
*          7    IST3 ASCII INTERPRETER
*          8    VIKING X CONTROLWARE RESIDENT 
* 
**
* 
*        FILE NUMBERS OF DISK RECORDS  (NEW)
*          3    IST2 RESIDENT (21/12 BIT PCN) 
*          4    IST2/3 INTERPRETER
*          5    IST3 RESIDENT (21/12 BIT PCN) 
*          6    IST2/IST3 ASCII/PLATO RESIDENT
*          7    IST3 ASCII INTERPRETER
*          8    VIKING X CONTROLWARE RESIDENT 
*          9    IST3 ASCII/GRAPHICS RESIDENT
* 
**
* /---   BLOCK      LDREQU     00 000   82/03/18  07.55 
         TITLE  LOADER EQUATES
* 
*               LOADER EQUATES
* 
SECTSZ   EQU    128     SECTOR SIZE 
 
ZSTACK   EQU    5000H   MICRO PROCESSOR STACK ADDRESS 
 
INTADR   EQU    5300H   INTERPRETER FWA 
 
MLWA     EQU    7FFFH    MEMORY LWA 
 
*        TERMINAL TYPE EQUATES
 
VIKX     EQU    02           VIKING X SUB TYPE
IST3     EQU    01           IST3 SUB TYPE
IST2     EQU    00           IST2 SUB TYPE
* /---   BLOCK      ISTEQU     00 000   82/04/16  08.39 
         TITLE  IST TERMINAL EQUATES
* 
*               IST TERMINAL EQUATES
* 
CHARADR  EQU    2300H   LOAD ADDRESS OF CHARACTER SET 
* 
BLOCK0   EQU    08E5H   FWA OF BLOCK 00 OF RESIDENT.
* 
KA       EQU    41H          KEY CODE FOR THE A KEY 
KP       EQU    50H          KEY CODE FOR THE P KEY 
KG       EQU    47H          KEY CODE FOR THE G KEY 
TA       EQU    16H          TOUCH PANEL CODE FOR A 
TP       EQU    18H          TOUCH PANEL CODE FOR P 
TG       EQU    14H          TOUCH PANEL CODE FOR G 
* 
LDVAR    EQU    22B4H        LOADER VARIABLES 
CKSUMTBL EQU    22C8H        ASCII CHECKSUM TABLE FWA 
CHECKSUM EQU    22CAH        ASCII CHECKSUM 
LOADFLAG EQU    22CBH        3CH = FULL LOAD COMPLETE 
RESETFLG EQU    22CCH        3CH = SHORT RESET
MODE     EQU    22CDH        ASCII RESIDENT OPERATING MODE
LOADINFO EQU    22CEH        LOAD PARAMETERS
RUNINFO  EQU    22CFH        RUN PARAMETERS 
CLR      EQU    22D0H        LAST RESTART STORE 
M.LDFILE EQU    22E5H 
 
LDSOURCE EQU    0979H   LOAD SOURCE 
STRADR   EQU    097AH   INITIAL RESIDENT ADDRESS
FULLDF   EQU    08DEH   FULL LOAD COMPLETE FLAG 
MLWA     EQU    7FFFH   MEMORY LWA
MESADR0  EQU    99B0H   DISPLAY MESSAGE SCREEN ADDRESS
MESADR1  EQU    99C0H   DISPLAY MESSAGE SCREEN ADDRESS
MESADR2  EQU    99D0H   DISPLAY MESSAGE SCREEN ADDRESS
MESADR3  EQU    96E0H   DISPLAY MESSAGE SCREEN ADDRESS
MESADR4  EQU    9720H   DISPLAY MESSAGE SCREEN ADDRESS
MESADR5  EQU    99A0H   DISPLAY MESSAGE SCREEN ADDRESS
MESADR6  EQU    83B0H   DISPLAY MESSAGE SCREEN ADDRESS
MESADR7  EQU    9760H   DISPLAY MESSAGE SCREEN ADDRESS
NEXT     EQU    16H     NEXT KEY CODE 
 
 
* /---   BLOCK      ISTEQU     00 000   82/03/18  07.44 
* 
MNTSW    EQU    00      MAINTAINENCE SWITCHES 
KBDATA   EQU    01      KEY BOARD DATA
TPDATA   EQU    02      TOUCH PANEL DATA
IDLOW    EQU    03           READ LOWER BITS OF ID
IDUP     EQU    04           READ UPPER BITS OF ID
EXTDATI  EQU    05      INPUT EXTERNAL DATA 
EXTSTAT  EQU    06      INPUT EXTERNAL STATUS 
SYSSTAT  EQU    07      TERMINAL SYSTEM STATUS
CLADATA  EQU    08      CLA DATA
* 
PNLLTS   EQU    00      PANEL LIGHTS
TXLOW    EQU    01           TRANSMIT LOWER BITS
TXUP     EQU    02           TRANSMIT UPPER BITS
BLKERS   EQU    03      SCREEN BULK ERASE 
INTMSK   EQU    04      PROCESSOR INTERRUPT MASK
ALARM    EQU    05      SOUND AUDIBLE ALARM 
EXTDATO  EQU    06      OUTPUT EXTERNAL DATA
EXTCNTL  EQU    07      OUTPUT EXTERNAL CONTROL 
* 
*        TERMINAL SYSTEM STATUS 
* 
PCRDY    EQU    01           PLATO CHARACTER READY
HWFLG    EQU    02           HARDWARE FLAG (POWER-ON/RESET) 
PCREQ    EQU    04           PLATO CHARACTER REQUEST
KDRDY    EQU    08           KEYBOARD DATA READY
TDRDY    EQU    10H          TOUCH PANEL DATA READY 
TMOUT    EQU    20H          I/O TIME-OUT 
RESET    EQU    40H          RESET SWITCH 
BERAS    EQU    80H          BULK ERASE IN PROGRESS 
 
* /---   BLOCK      VXEQU      00 000   82/03/18  07.50 
         TITLE     VIKING X TERMINAL EQUATES
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        I/O FUNCTION EQUATES 
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        8250 UART REGISTERS
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
UDATA    EQU       00         8250 TRANSMIT/RECEIVE DATA
UINTR    EQU       01         8250 INTERRUPT ENABLE REGISTER
UINTI    EQU       02         8250 INTERRUPT ID REGISTER
ULCLR    EQU       03         8250 LINE CONTROL REGISTER
UMCLR    EQU       04         8250 MODEM CONTROL REGISTER 
ULSTR    EQU       05         8250 LINE STATUS REGISTER 
UMSTR    EQU       06         8250 MODEM STATUS REGISTER
UBRLL    EQU       00         8250 BAUD RATE DIVISOR LATCH L
UBRLU    EQU       01         8250 BAUD RATE DIVISOR LATCH U
* /---   BLOCK      VXEQU      00 000   82/01/12  13.12 
         TITLE     CTC DEFINITIONS
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        Z80-CTC
* 
*        THE Z80-CTC HAS FOUR CHANNELS.  CHANNEL 3
*        IS USED FOR THE RESIDENT 17.5 MSEC CLOCK.
*        CHANNELS 1 AND 2 ARE NOT AVAILABLE AS THEY 
*        ARE USED AS THE TRANSMIT CLOCK FOR THE 8 BIT 
*        COMM PORT. CHANNEL 0 IS NOT USED.
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
TIMER    EQU       00H        BASE ADDRESS OF CTC 
 
TIMER0   EQU       TIMER+00   CHANNEL 0 
TIMER1   EQU       TIMER+01   CHANNEL 1 
TIMER2   EQU       TIMER+02   CHANNEL 2 
TIMER3   EQU       TIMER+03   CHANNEL 3 
TC       EQU       205        TIME CONSTANT FOR 8.75 MSEC 
TRESET   EQU       03         CONTROL BYTE FOR TIMER RESET
TSETUP   EQU       0B7H       CONTROL BYTE TO,
*                              RESET TIMER, TC FOLLOWS, 
*                              PRESCALER = 256, TIMER MODE, 
*                              ENABLE INTERRUPT.
 
*        TIME CONSTANT (TC) FOLLOWS CONTROL BYTE IF 
*         BIT 2 OF CONTROL BYTE SET.
*        TIMER MODE;
*                  INPUT CLOCK = 6 MHZ
*                  PRESCALER (P) USED (16 OR 256) 
*                  PERIOD = CLOCK X P X TC
*        COUNTER MODE;
*                  INPUT CLOCK = 1.8432 MHZ 
*                  PRESCALER NOT USED 
*                  PERIOD = CLOCK X TC
* 
*        OUTPUT TO Z80-CTC
*                  BIT 0      0 = VECTOR, 1 = CONTROL 
*            CONTROL
*                  BIT 1      0 = CONTINUE, 1 = RESET 
*                  BIT 2      0 = NO TC, 1 = TC FOLLOWS 
*                  BIT 3      0 = AUTO TRIG., 1 = CLOCK TRIG
*                  BIT 4      0 = FALL EDGE, 1 = RISING EDGE
*                  BIT 5      0 = PRESCALER 16, 1 = 256 
*                  BIT 6      0 = TIMER MODE, 1 = COUNTER 
*                  BIT 7      0 = DISABLE INT., 1 = ENABLE
*            VECTOR (LOWER 8 BITS OF INT. VECTOR) 
*                  BIT 1, 2   00 = CHANNEL 0
*                             01 = CHANNEL 1
*                             10 = CHANNEL 2
*                             11 = CHANNEL 3
*                  BITS 3 - 7   ADDRESS BITS
* /---   BLOCK      VXEQU      00 000   81/12/08  10.15 
         TITLE     5037 CRT CONTROLLER
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        5037 CRT CONTROLLER
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
CRT      EQU       10H        BASE ADDRESS OF CRT CONTROLLER
 
CRTRG0   EQU       CRT+0      HORIZONTAL LINE COUNT 
CRTRG1   EQU       CRT+1      SYNC WIDTH AND DELAY
CRTRG2   EQU       CRT+2      SCANS PER DATA ROW
CRTRG3   EQU       CRT+3      NUMBER OF LINES 
CRTRG4   EQU       CRT+4      SCANS PER LINE
CRTRG5   EQU       CRT+5      NUMBER OF SCANS TO TOP LINE 
CRTRG6   EQU       CRT+6      LAST LINE 
CRTRDY   EQU       CRT+8      READ CURSOR Y COORDINATE
XRTRDX   EQU       CRT+9      READ CURSOR X COORDINATE
CRTRST   EQU       CRT+10     RESET 
CRTCRL   EQU       CRT+11     SCROLL
CRTLDX   EQU       CRT+12     LOAD CHARACTER COUNT
CRTLDY   EQU       CRT+13     LOAD LINE COUNT 
CRTST    EQU       CRT+14     START CRT 
* /---   BLOCK      VXEQU      00 000   82/01/13  08.50 
         TITLE     8250 KEYBOARD UART DEFINITIONS 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        8250 KEYBOARD UART 
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
UKYBD    EQU       20H        BASE ADDRESS OF KEYBOARD UART 
 
* KEYBOARD TRANSMIT DATA REGISTER (OUTPUT)
*        EQU       UKYBD+UDATA
LCKLTO   EQU       00H        TURN OFF LOCK LIGHT ON KYBD 
 
* KEYBOARD RECEIVE DATA REGISTER (INPUT)
*        EQU       UKYBD+UDATA
 
* KEYBOARD INTERRUPT ENABLE REGISTER (OUTPUT) 
*        EQU       UKYBD+UINTR
 
KBERXI   EQU       01H        ENABLE RECEIVE DATA READY INT 
KBETXI   EQU       02H        ENABLE TRANSMIT DATA REQ INT
KBELSI   EQU       04H        ENABLE LINE STATUS INTERRUPT
KBEMSI   EQU       08H        ENABLE MODEM STATUS INTERRUPT 
 
* KEYBOARD INTERRUPT ID REGISTER (INPUT)
*        EQU       UKYBD+UINTI
 
* KEYBOARD LINE CONTROL REGISTER (OUTPUT) 
*        EQU       UKYBD+ULCLR
 
KBWL5    EQU       00H        WORD LENGTH 5 BITS
KBWL6    EQU       01H        WORD LENGTH 6 BITS
KBWL7    EQU       02H        WORD LENGTH 7 BITS
KBWL8    EQU       03H        WORD LENGTH 8 BITS
KBSB1    EQU       00H        1 STOP BIT
KBSB2    EQU       04H        2 STOP BITS 
KBPEN    EQU       08H        ENABLE PARITY 
KBPEV    EQU       10H        EVEN PARITY 
KBDLE    EQU       80H        BAUD RATE DIVITOR LATCH 
 
* MODEM CONTROL REGISTER (OUTPUT) 
*        EQU       UKYBD+UMCLR
 
FCBIT2   EQU       01H        FOREIGN CHARACTER ROM BIT 2 
ALARMH   EQU       02H        ALARM HIGH
FCBIT1   EQU       04H        FOREIGN CHARACTER ROM BIT 1 
FCBIT0   EQU       08H        FOREIGN CHARACTER ROM BIT 0 
KBLOOP   EQU       10H        PLACE UART IN LOOP BACK MODE
 
* KEYBOARD LINE STATUS REGISTER (INPUT) 
*        EQU       UKYBD+ULSTR
 
KBDR     EQU       01H        DATA READY
KBOR     EQU       02H        OVERRUN ERROR 
KBPE     EQU       04H        PARITY ERROR
KBFE     EQU       08H        FRAMING ERROR 
KBBK     EQU       10H        BREAK RECEIVED
KBTXHE   EQU       20H        TRANSMIT HOLDING REG EMPTY
KBTXSE   EQU       40H        TRANSMIT SHIFT REG EMPTY
 
* MODEM STATUS REGISTER (INPUT) 
*        EQU       UKYBD+UMSTR
 
LPSW     EQU       10H        LOOP BACK SWITCH ACTIVE 
RSTSW    EQU       20H        RESET SWITCH ACTIVE 
ROMPK    EQU       40H        ROM PACK INSTALLED
BATLOW   EQU       80H        BATTERY LOW 
 
* BAUD RATE DIVISOR LATCH LOWER (OUTPUT)
*        EQU       UKYBD+UBRLL
 
KBBRL    EQU       0CH        BAUD RATE LOWER VALUE (9600)
 
* BAUD RATE DIVISOR LATCH UPPER (OUTPUT)
*        EQU       UKYBD+UBRLU
 
KBBRU    EQU       00H        BAUD RATE UPPER VALUE (9600)
* /---   BLOCK      VXEQU      00 000   81/11/17  09.12 
         TITLE     8255 I/O PORT DEFINITIONS
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        8255 I/O PORTS 
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
PORT     EQU       30H        BASE ADDRESS OF 8255 I/O PORTS
 
PORTA    EQU       PORT+00    ADDRESS OF PORT A (OUTPUT)
 
LPSTRB   EQU       01H        LIGHT PEN STROBE
LPHIT    EQU       02H        LIGHT PEN HIT 
INTCLK   EQU       40H        INTERNAL CLOCK ENABLE 
EVIDEO   EQU       80H        ENABLE VIDEO
 
PORTB    EQU       PORT+01    ADDRESS OF PORT B (OUTPUT)
*                               (INTERRUPT MASK)
 
*     01   COMM PORT INTERRUPT
*     02   21/12 BIT PCN INTERRUPT
*     04   DUAL SERIAL PORT 
*     08   PARALLEL PORT
*     10   TOUCH PANEL
*     20   KEYBOARD 
*     40   TIMER
*     80   MEMORY PARITY ERROR
 
PORTC    EQU       PORT+03    ADDRESS OF PORT C (OUTPUT)
 
ALRON    EQU       00H        ALARM ON
ALROF    EQU       01H        ALARM OFF 
BLKCR    EQU       02H        BLINK CURSOR
SLDCR    EQU       03H        SOLID CURSOR
EBLINK   EQU       04H        ENABLE BLINK
DBLINK   EQU       05H        DISABLE BLINK 
LN80     EQU       06H        80 CHARACTERS PER LINE
LN132    EQU       07H        132 CHARACTERS PER LINE 
NORBK    EQU       08H        NORMAL BACKGROUND 
INVBK    EQU       09H        INVERSE BACKGROUND
UDCR     EQU       0AH        UNDERLINE CURSOR
BXCR     EQU       0BH        SOLID BOX CURSOR
PLATO    EQU       0CH        ENABLE PLATO CHARACTER GEN
RAMGEN   EQU       0DH        ENABLE RAM CHARACTER GEN
RFRSDS   EQU       0EH        DISABLE REFRESH 
RFRSEN   EQU       0FH        ENABLE REFRESH
* /---   BLOCK      VXEQU      00 000   81/11/18  07.22 
         TITLE     8250 COMM LINE UART DEFINITIONS
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        8250 COMM LINE UART
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
UCOMM    EQU       40H        BASE ADDRESS OF COMM LINE UART
 
* COMM TRANSMIT DATA (OUTPUT) 
*        EQU       UCOMM+UDATA
 
* COMM RECEIVE DATA (INPUT) 
*        EQU       UCOMM+UDATA
 
* COMM INTERRUPT ENABLE REGISTER (OUTPUT) 
*        EQU       UCOMM+UINTR
 
CERXI    EQU       01H        ENABLE RECEIVE DATA READY INT 
CETXI    EQU       02H        ENABLE TRANSMIT DATA REQ INT
CELSI    EQU       04H        ENABLE LINE STATUS INTERRUPT
CEMSI    EQU       08H        ENABLE MODEM STATUS INTERRUPT 
 
* COMM INTERRUPT ID REGISTER (INPUT)
*        EQU       UCOMM+UINTI
 
* COMM LINE CONTROL REGISTER (OUTPUT) 
*        EQU       UCOMM+ULCLR
 
CWL7     EQU       02H        WORD LENGTH 7 BITS
CWL8     EQU       03H        WORD LENGTH 8 BITS
CSB1     EQU       00H        1 STOP BIT
CSB2     EQU       04H        2 STOP BITS 
CPEN     EQU       08H        ENABLE PARITY 
CPEV     EQU       10H        EVEN PARITY 
CBRK     EQU       40H        SEND BREAK SIGNAL 
CDLE     EQU       80H        DIVISOR LATCH ENABLE
 
* COMM MODEM CONTROL REGISTER (OUTPUT)
*        EQU       UCOMM+UMCLR
 
CDTR     EQU       01H        DTR ON
CRTS     EQU       02H        RTS ON
CSRTS    EQU       04H        SECONDARY RTS ON
COUT2    EQU       08H        NOT USED
CLOOP    EQU       10H        PLACE UART IN LOOP BACK MODE
 
* COMM LINE STATUS REGISTER (INPUT) 
*        EQU       UCOMM+ULSTR
 
CDR      EQU       01H        DATA READY
CORE     EQU       02H        OVERRUN ERROR 
CPE      EQU       04H        PARITY ERROR
CFE      EQU       08H        FRAMING ERROR 
CBK      EQU       10H        BREAK RECEIVED
CTXHE    EQU       20H        TRANSMIT HOLDING REG EMPTY
CTXSE    EQU       40H        TRANSMIT SHIFT REG EMPTY
 
* COMM MODEM STATUS REGISTER (INPUT)
*        EQU       UCOMM+UMSTR
 
CCTS     EQU       10H        CTS ON
CDSR     EQU       20H        DSR ON
CRI      EQU       40H        RING INDICATOR ON 
CCO      EQU       80H        CARRIER ON
 
* COMM BAUD RATE DIVISOR LATCH LOWER (OUTPUT) 
*        EQU       UCOMM+UBRLL
 
* COMM BAUD RATE DIVISOR LATCH UPPER (OUTPUT) 
*        EQU       UCOMM+UBRLU
* /---   BLOCK      VXEQU      00 000   82/03/31  13.07 
         TITLE     LED LATCH DEFINITIONS
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        LED LATCH
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
LEDOUT   EQU       50H        BASE ADDRESS OF LED LATCH 
 
LTERR    EQU       01H        ERROR 
LTALRT   EQU       02H        ALERT 
LTKBLK   EQU       04H        KEYBOARD LOCKED 
LTMSG    EQU       08H        MESSAGE WAITING 
LTDSR    EQU       10H        DSR ON
LTPRG1   EQU       20H        PROGRAMMABLE IND. 1 
LTPRG2   EQU       40H        PROGRAMMABLE IND. 2 
LTPRG3   EQU       80H        PROGRAMMABLE IND. 3 
         TITLE     BANK SELECT DEFINITIONS
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        BANK SELECT EQUATES
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
BANK     EQU       70H        ADDRESS OF BANK SELECT REG. 
 
B0       EQU       00         BANK 0 ROM, BLOCK 0 
B1       EQU       02         BANK 1 RAM, BLOCK 0 
B2       EQU       0CH        BANK 2 RAM, BLOCK 4 
B3       EQU       10H        BANK 3 RAM, BLOCK 8 
B4       EQU       00         BANK 4 RAM, BLOCK C 
B5       EQU       00         BANK 5 ROM PACK, BLOCK 8
B6L      EQU       00         BANK 6 NVM, BLOCK 4 
B6U      EQU       40H        BANK 6 NVM, BLOCK C 
B7L      EQU       01         BANK 7 GRAPHICS, BLOCK 0
B7U      EQU       30H        BANK 7 GRAPHICS, BLOCK 8
B8L      EQU       04         BANK 8 GRAPHICS, BLOCK 4
B8U      EQU       0C0H       BANK 8 GRAPHICS, BLOCK C
* 
*        LD     A,B7L+B8L+B3+B4 
*        OUT    (BANK),A     SELECTS LOWER GRAPHICS 
* 
ROMPACK  EQU    8000H        FWA OF ROM PACK
* /---   BLOCK      VXEQU      00 000   82/03/18  07.36 
         TITLE     8250 PORT A AND B DEFINITIONS
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        8250 SERIAL PORTS A AND B
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
USERA    EQU       80H        BASE ADDRESS OF SERIAL CHAN A 
USERB    EQU       90H        BASE ADDRESS OF SERIAL CHAN B 
 
* SERIAL CHANNEL TRANSMIT DATA REGISTER (OUTPUT)
*        EQU       USERA+UDATA    CHANNEL A 
*        EQU       USERB+UDATA    CHANNEL B 
 
* SERIAL CHANNEL RECEIVE DATA REGISTER (INPUT)
*        EQU       USERA+UDATA    CHANNEL A 
*        EQU       USERB+UDATA    CHANNEL B 
 
* SERIAL CHANNEL INTERRUPT ENABLE REGISTER (OUTPUT) 
*        EQU       USERA+UINTR    CHANNEL A 
*        EQU       USERB+UINTR    CHANNEL B 
 
* SERIAL CHANNEL INTERRUPT ID REGISTER (INPUT)
*        EQU       USERA+UINTI    CHANNEL A 
*        EQU       USERB+UINTI    CHANNEL B 
 
* SERIAL CHANNEL LINE CONTROL REGISTER (OUTPUT) 
*        EQU       USERA+ULCLR    CHANNEL A 
*        EQU       USERB+ULCLR    CHANNEL B 
 
* SERIAL CHANNEL MODEM CONTROL REGISTER (OUTPUT)
*        EQU       USERA+UMCLR    CHANNEL A 
*        EQU       USERB+UMCLR    CHANNEL B 
 
* SERIAL CHANNEL LINE STATUS REGISTER (INPUT) 
*        EQU       USERA+ULSTR    CHANNEL A 
*        EQU       USERB+ULSTR    CHANNEL B 
 
* SERIAL CHANNEL MODEM STATUS REGISTER (INPUT)
*        EQU       USERA+UMSTR    CHANNEL A 
*        EQU       USERB+UMSTR    CHANNEL B 
 
* SERIAL CHANNEL BAUD RATE DIVISOR LATCH LOWER (OUTPUT) 
*        EQU       USERA+UBRLL    CHANNEL A 
*        EQU       USERB+UBRLL    CHANNEL B 
 
* SERIAL CHANNEL BAUD RATE DIVISOR LATCH UPPER (OUTPUT) 
*        EQU       USERA+UBRLU    CHANNEL A 
*        EQU       USERB+UBRLU    CHANNEL B 
 
* 
*     PRINTER MODEM STATUS REGISTER 
*     10   PRINTERS RTS 
*     20   PRINTERS DTR 
*     40   PORT TEST ENABLED
*     80   PRINTERS 3/4 FULL
         TITLE     PARALLEL I/O CHANNEL DEFINITIONS 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        PARALLEL CHANNEL 
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
PCHAN    EQU    0A0H         DEVICE ADDRESSES A0-BF HEX 
PSTAT    EQU    88H          PARALLEL PORT STATUS 
TIMOUT   EQU    01           CHANNEL TIME-OUT 
INTPND   EQU    02           INTERRUPT PENDING
*               BIT 0 = CHANNEL TIME OUT, (50 MSEC) 
*               BIT 1 = EXTERNAL INTERRUPT
*               BIT 2 = EXTERNAL FIXED DISK INTERRUPT 
* /---   BLOCK      VXEQU      00 000   82/03/18  08.40 
         SPACE     4
*        GRAPHICS PRINTER EQUATES 
 
DATAFCN  EQU       PCHAN+0AH  000NNNN0 PRINTER DATA ADDRESS 
CNTLFCN  EQU       PCHAN+0BH  000NNNN1 PRINTER CTRL ADDRESS 
 
MRESET0  EQU       00H        RESET INTERFACE 
MRESET1  EQU       01H        RESET PTR 
SECSTAT  EQU       09H        REQUEST SECONDARY STATUS. 
READID   EQU       08H        READ DEVICE ID. 
STIMER   EQU       0EH        START TIMER.
* 
C.ENQ    EQU       05H        DOT ROW PREAMBLE
C.LF     EQU       0AH        LINE / ROW FEED 
C.FF     EQU       0CH        FORM FEED 
         SPACE     4
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        GRAPHICS EQUATES 
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
BULKW    EQU    0FCH         GRAPHICS BULK WRITE
UNBLNKG  EQU    0FDH         UNBLANK GRAPHICS VIDEO 
SEL512   EQU    0FEH         SELECT 512 LINES 
BLNKG    EQU    0FFH         BLANK GRAPHICS VIDEO 
VTPDAT   EQU    0FCH         INPUT TOUCH PANEL DATA 
GSTAT    EQU    0FDH         GRAPHICS STATUS
*                            BIT 0 = BULK WRITE BUSY
*                            BIT 1 = TOUCH PANEL DATA READY 
SEL480   EQU    0FEH         INPUT SELECTS 480 LINES
 
R.SETDE  EQU    008AH        SET CURSOR TO (DE) 
R.DSTRNG EQU    0063H        DISPLAY DATA STRING
* /---   BLOCK      DISKEQU    00 000   82/03/18  07.30 
* 
*        EQUATE TABLES
* 
*               DISK EQUATES
* 
*               DISK I/O FUNCTION CODES 
DCNTL    EQU    0AFH    DISK CONTROL, WRITE 
DSTAT    EQU    0AFH    DISK STAT, READ 
DDATA    EQU    0AEH    DISK DATA, READ AND WRITE 
* 
*               DISK I/O COMMANDS 
DREAD    EQU    00      READ SECTORS
DWRITE   EQU    02      WRITE SECTORS 
DID      EQU    04      READ DISK CONTROLLER ID 
DLDRES   EQU    06      LOAD TERMINAL RESIDENT
DRESET   EQU    08      DISK RESET
RDFILE   EQU    12      READ DISK FILE
* 
*               DISK STATUS 
IDLE     EQU    40H     CONTROLLER IDLE STATUS
BUSY     EQU    44H     CONTROLLER BUSY STATUS
SCOMD    EQU    48H     WAITING FOR CMD COMPLIMENT
SRXFER   EQU    4AH     READY FOR READ TRANSFER 
SWXFER   EQU    4CH     READY FOR WRITE TRANSFER
SDONE    EQU    50H     COMMAND PROCESSING COMPLETE.
* 
* 'COMMAND ERRORS 
SCODD     EQU    80H        ODD-NUMBERED COMMAND RECEIVED.
SCOOR     EQU    81H        COMMAND OUT OF RANGE. 
SCCOMP    EQU    82H        BAD COMMAND COMPLEMENT. 
* 
* 'PARAMETER ERRORS 
SDRIVE    EQU    83H        BAD DRIVE NUMBER. 
SSIDE     EQU    84H        BAD SIDE NUMBER.
STRK      EQU    85H        BAD TRACK NUMBER. 
SSECT     EQU    86H        BAD SECTOR NUMBER.
SDEN      EQU    87H        BAD DENSITY.
SPSUM     EQU    88H        PARAMETER CHECKSUM FAILURE. 
SNSCT     EQU    89H         BAD NUMBER OF SECTORS. 
* 
* 'SEEK / RESTORE ERRORS
SSCRC     EQU    90H         SEEK CRC ERROR.
SSEEK     EQU    91H         SEEK ERROR.
SSTIME    EQU    92H         SEEK TIMEOUT.
SREST     EQU    93H         RESTORE TIMEOUT. 
* 
* 'READ/WRITE ERRORS
SNRDY     EQU    0ADH        DESIRED DRIVE NOT READY. 
SSGL      EQU    0AEH        ATTEMPTED ACCESS TO SIDE 1 
* 
* 'READ ERRORS
SRTIME    EQU    0B0H        DISK READ TIMEOUT. 
SRDATA    EQU    0B1H        LOST DATA. 
SRCRC     EQU    0B2H        CRC ERROR. 
SRRNF     EQU    0B3H        RECORD NOT FOUND.
SRTTO     EQU    0B4H        TERMINAL TRANSFER TIMEOUT. 
SREOS     EQU    0B5H        TRIED TO READ PAST END OF SIDE.
* 
* 'WRITE ERRORS 
SWTTO     EQU    0C0H        TERMINAL TRANSFER TIMEOUT. 
SWTIME    EQU    0C1H        DISK WRITE TIMEOUT.
SWDATA    EQU    0C2H        LOST DATA. 
SWCRC     EQU    0C3H        CRC ERROR. 
SWRNF     EQU    0C4H        RECORD NOT FOUND.
SWFAULT   EQU    0C5H        DISK WRITE FAULT.
SWPROT    EQU    0C6H        DISK IS WRITE-PROTECTED. 
SWCSUM    EQU    0C7H        CHECKSUMS DO NOT MATCH.
* 
* /---   BLOCK      VIKINGP    00 000   81/10/20  10.56 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
* NVM CONFIGURATION INFORMATION 
*        TERMINAL INSTALLATION PARAMETERS 
*        CMOS BANK 6
* 
*        X01F    CHECKSUM 
*        X020    MODE 1 PARAMETERS
*        X040    MODE 2 PARAMETERS
*        X060    MODE 3 PARAMETERS
*        X080    MODE 4 PARAMETERS
*        X0A0    MODE 5 PARAMETERS
*        X0C0    MODE 6 PARAMETERS
*        X0E0    MODE 3 NAME
*        X0E8    MODE 4 NAME
*        X0F0    MODE 5 NAME
*        X0F8    MODE 6 NAME
* 
* MODE BYTE 1  X000 
*        01          MODE ENABLE
*        02          SECURITY ENABLE
*        04          OPERTOR SELECT SOURCE/FILE 
*        08          LOAD ENABLE
* MODE BYTE 2  X001 
*        01          LOAD FROM DISK 
*        02          USE INTERNAL 1200 BAUD MODEM 
*        04          CURRENT LOOP ENABLE
*        08          AUTO DIAL
* MODE BYTE 3  X002 
*        01          HOST 8 BITS
*        02          HOST PARITY ENABLE 
*        04          HOST PARITY EVEN 
*        08          HOST 2 STOP BITS 
* MODE BYTE 4  X003 
*        01          DTR SWITCHED 
*        02          RTS SWITCHED 
*        04          REPEAT DISABLED
*        08          DATA ONLY OPERATION
* MODE BYTE 5  X004 
*        01          HOME LOWER LEFT
*        02          AUTO LINE FEED ENABLE
*        04          PACING ENABLE
*        08          BIAS ENABLED 
* MODE BYTE 6  X005 
*        01          NOT USED 
*        02          NOT USED 
*        04          NOT USED 
*        08          NOT USED 
****
*        OPERATER PARAMETERS
****
* OPERATOR BYTE 1  X006 
*        01          LOCAL
*        02          PRINTER SELECTED 
*        04          MARGIN ALERT ENABLED 
*        08          ALERT LOUD 
* OPERATOR BYTE 2  X007 
*        01          SHIFT LOCK 
*        02          NOT  USED
*        04          ROLL SCREEN
*        08          NATIVE MODE / LARGE CYBER
* OPERATOR BYTE 3  X008 
*        01          BACKGROUND LIGHT 
*        02          CURSOR BOX 
*        04          CURSOR SOLID ON
*        08          NOT USED 
* /---   BLOCK      VIKINGP    00 000   81/10/28  08.25 
* OPERATOR BYTE 4  X009 
*        01      FULL DUPLEX
*        02      132 CHARACTERS PER LI
*        04      30 LINES 
*        08      TRANSPARENT
* AUTO DIAL NUMBER 12 BYTES  X00A 
* DEFAULT FILE     2 BYTES  X016
* TRANSMIT BAUD    1 BYTE  X018 
* RECEIVE BAUD     1 BYTE  X019 
* SECURITY CODE    1 BYTE  X01A 
****
*        TERMINAL PARAMETERS
****
* TERMINAL BYTE 1  X01B 
*        01        64K RAM OPTION 
*        02        TOUCH PANEL OPTION 
*        04        DUAL SERIAL OPTION 
*        08        GRAPHIC PRINTER OPTION 
* TERMINAL BYTE 2  X01C 
*        01        FLEXIBLE DISK OPTION 
*        02        21/12 BIT PCN OPTION 
*        04        INTERNAL 1200 BAUD MODEM 
*        08        ISO 3243 KEYBOARD OPTION 
* TERMINAL BYTE 3  X01C 
*        01        NOT USED 
*        02        NOT USED 
*        04        NOT USED 
*        08        NOT USED 
* TERMINAL BYTE 4  X01D 
*        01        AUTO SELECT ENABLE 
*        02        50 HZ POWER SOURCE 
*        04        NOT USED 
*        08        NOT USED 
* TERMINAL BYTE 5  X01E 
*        01        NOT USED 
*        02        NOT USED 
*        04        NOT USED 
*        08        NOT USED 
* TERMINAL BYTE 6  X01F 
*        01        NOT USED 
*        02        NOT USED 
*        04        NOT USED 
*        08        NOT USED 
* SCREEN MOVE X DELTA  X020 
* SCREEN MOVE Y DELTA 0-7  X021 
* LANGUAGE 0-7
* TERMINAL ID 0000-FFFF 
* CHANNEL A PARAMETERS
*        01        2 STOP BITS
*        02        PARITY EVEN
*        04        PARITY DISABLED
*        08        BI-DIRECTIONAL PORT
* CHANNEL A BAUD RATE 0-F 
* CHANNEL B PARAMETERS
* CHANNEL B BAUD RATE 0-F 
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* /---   BLOCK      VIKINGP    00 000   81/10/20  08.54 
 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
*        I/O FUNCTION CODES 
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
* 00     Z80B TIMER-0 
* 01     Z80B TIMER-1 
* 02     Z80B TIMER-2 
* 03     Z80B TIMER-3 
* 10     CRT 5037 CRT CONTROLLER       LOAD CONTROL REG 0 
* 11     CRT 5037 CRT CONTROLLER       LOAD CONTROL REG 1 
* 12     CRT 5037 CRT CONTROLLER       LOAD CONTROL REG 2 
* 13     CRT 5037 CRT CONTROLLER       LOAD CONTROL REG 3 
* 14     CRT 5037 CRT CONTROLLER       LOAD CONTROL REG 4 
* 15     CRT 5037 CRT CONTROLLER       LOAD CONTROL REG 5 
* 16     CRT 5037 CRT CONTROLLER       LOAD CONTROL REG 6 
* 18     CRT 5037 CRT CONTROLLER       READ CURSOR LINE ADDR
* 19     CRT 5037 CRT CONTROLLER       READ CURSOR CHAT ADDR
* 1A     CRT 5037 CRT CONTROLLER       RESET
* 1B     CRT 5037 CRT CONTROLLER       UP SCROLL
* 1C     CRT 5037 CRT CONTROLLER       LOAD CURSOR CHAR ADDR
* 1D     CRT 5037 CRT CONTROLLER       LOAD CURSOR LINE ADDR
* 1E     CRT 5037 CRT CONTROLLER       START TIMING CHAIN 
* 20     KEYBOARD UART 8250            DLAB=0 READ RX BUFFER
* 20     KEYBOARD UART 8250            DLAB=0 TX HOLDING REG
* 21     KEYBOARD UART 8250            DLAB=0 INTERRUPT ENABLE
* 22     KEYBOARD UART 8250            INTERRUPT ID REG 
* 23     KEYBOARD UART 8250            LINE CONTROL REG 
* 24     KEYBOARD UART 8250            MODEM CONTROL REG
* 25     KEYBOARD UART 8250            LINE STATUS REG
* 26     KEYBOARD UART 8250            MODEM STATUS REG 
* 27     KEYBOARD UART 8250            NOT USED 
* 20     KEYBOARD UART 8250            DLAB=1 DIVISOR LATCH LSB 
* 21     KEYBOARD UART 8250            DLAB=1 DIVISOR LATCH MSB 
* 30     8255 I/O EXPANDER             PORT A 
* 31     8255 I/O EXPANDER             PORT B 
* 32     8255 I/O EXPANDER             PORT C 
* 33     8255 I/O EXPANDER             CONTROL
* 40     COMM UART 8250                DLAB=0, READ RX BUFFER 
* 40     COMM UART 8250                DLAB=0, TX HOLDING REG 
* 41     COMM UART 8250                DLAB=0, INT. ENABLE
* 42     COMM UART 8250                INTERRUPT ID REG 
* 43     COMM UART 8250                LINE CONTROL REG 
* 44     COMM UART 8250                MODEM CONTROL REG
* 45     COMM UART 8250                LINE STATUS REG
* 46     COMM UART 8250                MODEM STATUS REG 
* 47     COMM UART 8250                NOT USED 
* 40     COMM UART 8250                DLAB=1, DIVISOR LSB
* 41     COMM UART 8250                DLAB=1, DIVISOR MSB
* 50     LEDS 
* 5F     LEDS 
* 60     LIGHT PEN REG 1               HORZ COURT REG 
* 61     LIGHT PEN REG 2               VERT COURT + SCAN CNT
* 70     BANK SELECT REG
* /---   BLOCK      INIT       00 000   82/09/07  10.15 
         TITLE  START 
**
* 
*        STARTING POINT OF LOADER 
* 
**
         SPACE  6 
**
* 
START    EQU    * 
* 
LADR     DEFW   ENTRY       LOAD ADDRESS
LLNTH    DEFW   ENDLDR      LOAD LENGTH 
ENTRY    EQU    * 
         JR     BEGIN 
         DEFW   NUMB
* 
*CALL,ZDATE 
         TITLE  BEGIN 
**
* 
*        'THIS ROUTINE DISABLES THE TERMINAL INTERRUPTS, SETS 
*        THE STACK POINTER, CLEARS THWE SCREEN, AND CLEARS
*        THE INTERPRETER MEMORY AREA. 
* 
 
BEGIN    EQU    * 
         DI                  DISABLE PROCESSOR INTERRUPTS 
         LD     (TTYPE),BC    SAVE TERMINAL TYPE. 
         LD     SP,ZSTACK    SET STACK POINTER
 
         LD     HL,INTADR 
         LD     DE,INTADR+1 
         LD     BC,MLWA-INTADR
         LD     (HL),00 
         LDIR                CLEAR INTERPRETER
 
         LD     A,03
         LD     (RTYCNT),A   SET RETRY COUNT
* 
         LD     A,(TTYPE) 
         CP     VIKX         TEST FOR VIKING X TERMINAL 
         JR     NZ,BEGIN1    JUMP IF NOT VIKING X 
* 
*        VIKING X INITIALIZE
* 
 
         LD     A,B0+B2+B3+B4   SELECT RES ROM
         OUT    (BANK),A       AND THEN OUTPUT TO PORT
* 
*        SET ADDRESSES FOR TERMINAL RESIDENT. 
* 
         LD     IX,PARMS
         LD     (IX+0),8     LOAD RESIDENT FIRMWARE NUMBER
         LD     (IX+1),2     LOAD NUMBER OF ADDITIONAL PARTS
         LD     (IX+2),4     LOAD PLATO INTERPRETER 
         LD     (IX+3),1     LOAD NUMBER OF ADDITIONAL PARTS
 
         LD     DE,0A17H   SET TO COL 10, LINE 23 
         CALL   R.SETDE 
         LD     DE,VMES11  DISPLAY LOAD MESSAGE 
         CALL   VDMSG 
 
         JP     EXEC
* /---   BLOCK      INIT       00 000   82/04/21  08.19 
* 
*        IST INITIALIZE 
* 
**
* 
*        'THIS ROUTINE DISABLES THE TERMINAL INTERRUPTS, SETS 
*        THE STACK POINTER, CLEARS THWE SCREEN, AND CLEARS
*        THE INTERPRETER MEMORY AREA. 
* 
* 
*        INPUT FRONT PANEL SWITCHES AND DETERMINE 
*        WHEATHER TO LOAD FROM DEFAULT SWITCH SETTING,
*        OR TO DISPLAY SELECT MESSAGE.
*        (TTYPE) DETERMINE TERMINAL TYPE, 00 FOR IST2 AND 
*        01 FOR IST3. IF TERMINAL IS AN IST2, DO NOT LOAD 
*        ASCII GRAPHICS RESIDENT
* 
* 
BEGIN1   EQU    * 
         LD     A,00         TURN OFF INTERRUPT MASK. 
         OUT    (INTMSK),A
 
         LD     A,06
         OUT    (BLKERS),A      CLEAR SCREEN
         LD     A,0C1H          SELECT LOW
         OUT    (PNLLTS),A          RAM AREA OF MEMORY. 
* 
BGIN0    EQU    * 
         IN     A,(SYSSTAT)     INPUT TERMINAL STATUS 
         RLCA                    AND TEST FOR BULK ERASE
         JR     C,BGIN0           COMPLETED.
* 
         LD     A,(TTYPE) 
         CP     IST3         TEST FOR IST3
         JP     NZ,BGIN4      IF AN IST2
* 
         IN     A,(MNTSW)    LOAD SWITCH DATA 
         BIT    0,A            AND TEST FOR SELECT. 
         JR     NZ,BGIN1     GOTO SELECT
* 
         IN     A,(EXTSTAT)  ELSE INPUT DEFAULT 
         BIT    0,A            AND TEST FOR PLATO OR ASCII
         JP     NZ,BGIN6     GOTO ASCII 
         JP     BGIN5        ELSE LOAD PLATO
* 
*        DISPLAY PLATO/ASCII LOAD MESSAGE 
* 
BGIN1    EQU    * 
         LD     DE,MESADR7   LOAD SCREEN ADDRESS
         LD     IX,MES7      LOAD MESSAGE ADDRESS 
         CALL   MESSAGE        AND DISPLAY. 
         LD     DE,8B60H
         LD     IX,MES11
         CALL   MESSAGE 
 
BGIN1A   EQU    * 
         LD     DE,MESADR3   LOAD SCREEN ADDRESS
         LD     IX,MES5      LOAD MESSAGE ADDRESS 
         CALL   MESSAGE        AND DISPLAY. 
         LD     DE,MESADR4   LOAD SCREEN ADDRESS
         LD     IX,MES6      LOAD MESSAGE ADDRESS 
         CALL   MESSAGE        AND DISPLAY. 
         LD     DE,8AE0H
         LD     IX,MES12
         CALL   MESSAGE 
         LD     DE,8B20H
         LD     IX,MES13
         CALL   MESSAGE 
* /---   BLOCK      INIT       00 000   82/04/21  08.48 
* 
*        WAIT FOR KEYBOARD INPUT LETTERS A OR P 
* 
BGIN2    EQU    * 
         IN     A,(SYSSTAT)  INPUT TERMINAL STATUS
         BIT    3,A            TEST FOR KEYBOARD DATA 
         JR     Z,BGIN3 
* 
         IN     A,(KBDATA)   INPUT KEY CODE 
         AND    5FH          MASK OFF SHIFT CODE
         CP     KA              TEST FOR LETTER A 
         JP     Z,BGIN7 
         CP     KP              TEST FOR LETTER P 
         JP     Z,BGIN5 
         CP     KG              TEST FOR LETTER G 
         JP     Z,BGIN6 
* 
*        WAIT FOR TOUCH PANEL INPUT 
* 
BGIN3    EQU    * 
         IN     A,(SYSSTAT)  INPUT TERMINAL STATUS
         BIT    4,A          TEST FOR TOUCH PANEL DATA
         JR     Z,BGIN2      LOOP FOR INPUT 
* 
         LD     A,01
         OUT    (ALARM),A    SAY BEEB 
* 
         IN     A,(TPDATA)     ELSE INPUT THE DATA
         CP     TA           TEST FOR ASCII 
         JP     Z,BGIN7      LOAD ASCII PARAMETERS
* 
         CP     TA+1         TEST FOR ASCII 
         JP     Z,BGIN7      LOAD ASCII PARAMETERS
* 
         CP     TA+10H       TEST FOR ASCII 
         JP     Z,BGIN7      LOAD ASCII PARAMETERS
* 
         CP     TA-10H       TEST FOR ASCII 
         JP     Z,BGIN7      LOAD ASCII PARAMETERS
* 
         CP     TP           TEST FOR PLATO 
         JR     Z,BGIN5      LOAD PLATO PARAMETERS
* 
         CP     TP+1         TEST FOR PLATO 
         JR     Z,BGIN5      LOAD PLATO PARAMETERS
* 
         CP     TP+10H       TEST FOR PLATO 
         JR     Z,BGIN5      LOAD PLATO PARAMETERS
* 
         CP     TP-10H       TEST FOR PLATO 
         JR     Z,BGIN5      LOAD PLATO PARAMETERS
* 
         CP     TG           TEST FOR GRAPHICS
         JP     Z,BGIN6      LOAD GRAPHICS PARAMETERS 
* 
         CP     TG+1         TEST FOR GRAPHICS
         JP     Z,BGIN6      LOAD GRAPHICS PARAMETERS 
* 
         CP     TG+10H       TEST FOR GRAPHICS
         JP     Z,BGIN6      LOAD GRAPHICS PARAMETERS 
* 
         CP     TG-10H       TEST FOR GRAPHICS
         JP     Z,BGIN6      LOAD GRAPHICS PARAMETERS 
         JR     BGIN2 
* /---   BLOCK      INIT       00 000   82/09/21  08.08 
         SPACE  4 
* 
*        SET ADDRESSES FOR IST2 PLATO RESIDENT
* 
BGIN4    EQU    * 
         LD     A,(TTYPE+1) 
         CP     80H         TEST FOR IST2 21/12 BIT PCN 
         JP     Z,BGIN7      JUMP IF ASCII
 
         LD     IX,PARMS
         LD     (IX+0),03    LOAD RESIDENT RECORD NUMBER
         LD     (IX+1),01    LOAD NUMBER OF ADDED PARTS 
         LD     (IX+2),04    LOAD INTERPRETER RECORD NUMBER 
         LD     (IX+3),01    LOAD NUMBER OF ADDED PARTS 
         LD     HL,097AH
         LD     (BGN.ADR),HL    LOAD ADDR OF ENTRY ADDR 
         LD     HL,08E5H
         LD     (BLK0.ADR),HL   LOAD FWA OF BLOCK 0 
         LD     HL,0979H
         LD     (LDS.ADR),HL    LOAD SOURCE FLAG ADDR 
         LD     HL,08DEH
         LD     (FL.ADR),HL     LOAD FULL LOAD FLAG ADDR
         LD     DE,MESADR5      LOAD SCREEN ADDRESS 
         LD     IX,MES3         LOAD MESSAGE ADDRESS
         CALL   MESSAGE          AND DISPLAY. 
         JP     EXEC            LOAD RESIDENT 
* 
*        SET ADDRESSES FOR IST3 PLATO RESIDENT
* 
BGIN5    EQU    * 
         LD     IX,PARMS
         LD     (IX+0),05    LOAD RESIDENT RECORD NUMBER
         LD     (IX+1),01    LOAD NUMBER OF ADDED PARTS 
         LD     (IX+2),04    LOAD INTERPRETER RECORD NUMBER 
         LD     (IX+3),01    LOAD NUMBER OF ADDED PARTS 
         LD     HL,0140H
         LD     (BGN.ADR),HL    LOAD ADDR OF ENTRY ADDR 
         LD     HL,00B0H
         LD     (BLK0.ADR),HL   LOAD FWA OF BLOCK 0 
         LD     HL,0144H
         LD     (LDS.ADR),HL    LOAD SOURCE FLAG ADDR 
         LD     HL,SAVEI        LOAD SAVE ADDRESS 
         LD     (HL),3CH        LOAD FULL LOAD FLAG 
         INC    HL
         LD     (HL),3CH        LOAD RESET FLAG 
         INC    HL
         LD     (HL),80H        LOAD PLATO MODE FLAG
         INC    HL
         LD     A,(LOADINFO)     SAVE LOAD INFORMATION FLAG 
         RES    2,A             SET PLATO BIT 
         LD     (HL),A            AND SAVE. 
         INC    HL
         LD     (HL),A          LOAD RUN INFORMATION FLAG.
         LD     DE,MESADR5      LOAD SCREEN ADDRESS 
         LD     IX,MES3         LOAD MESSAGE ADDRESS
         CALL   MESSAGE          AND DISPLAY. 
         LD     DE,MESADR5      LOAD SCREEN ADDRESS 
         LD     IX,MES3         LOAD MESSAGE ADDRESS
         CALL   MESSAGE          AND DISPLAY. 
         JR     EXEC
* /---   BLOCK      INIT       00 000   82/04/21  21.12 
* 
*        SET ADDRESSES FOR IST3 ASCII GRAPHICS RESIDENT 
* 
BGIN6    EQU    * 
         LD     IX,PARMS
         LD     (IX+0),09    LOAD RESIDENT RECORD NUMBER
         LD     (IX+1),02    LOAD NUMBER OF ADDED PARTS 
         LD     (IX+2),07    LOAD INTERPRETER RECORD NUMBER 
         LD     (IX+3),01    LOAD NUMBER OF PART
         LD     HL,0041H
         LD     (BGN.ADR),HL    LOAD ADDR OF ENTRY ADDR 
         LD     HL,00F0H
         LD     (BLK0.ADR),HL   LOAD CHECKSUM TABLE ADDRESS 
         LD     HL,22C7H
         LD     (LDS.ADR),HL    LOAD SOURCE FLAG ADDR 
         LD     HL,SAVEI        LOAD SAVE ADDRESS 
         LD     (HL),3CH        LOAD FULL LOAD FLAG 
         INC    HL
         LD     (HL),00         LOAD RESET FLAG 
         INC    HL
         LD     (HL),00         LOAD ASCII MODE FLAG
         INC    HL
         LD     A,(LOADINFO)     SAVE LOAD INFORMATION FLAG 
         SET    2,A             SET ASCII BIT 
         LD     (HL),A
         INC    HL
         LD     (HL),A          LOAD RUN INFORMATION FLAG.
         LD     DE,MESADR5      LOAD SCREEN ADDRESS 
         LD     IX,MES9         LOAD MESSAGE ADDRESS
         CALL   MESSAGE          AND DISPLAY. 
         JR     EXEC
 
* 
*        SET ADDRESSES FOR IST2/IST3 ASCII PLATO RESIDENT 
* 
BGIN7    EQU    * 
         LD     IX,PARMS
         LD     (IX+0),6     LOAD RESIDENT FIRMWARE NUMBER
         LD     (IX+1),1     LOAD NUMBER OF ADDITIONAL PARTS
         LD     (IX+2),4     LOAD PLATO INTERPRETER 
         LD     (IX+3),1     LOAD NUMBER OF ADDITIONAL PARTS
 
         LD     DE,MESADR5      LOAD SCREEN ADDRESS 
         LD     IX,MES8         LOAD MESSAGE ADDRESS
         CALL   MESSAGE          AND DISPLAY. 
* 
* /---   BLOCK      EXEC       00 000   82/09/21  08.14 
         TITLE  LOADER EXEC 
**
* 
*        'THIS ROUTINE CALLS THE LOAD ROUTINES AND THE
*        CHECKSUM ROUTINES. 'IF THE CHECKSUM FAILS, THREE 
*        RETRIES ARE MADE TO RELOAD EITHER THE RESIDENT 
*        OR THE INTERPRETER AND CHECKSUM THE DATA.
*        'IF THE CHECKSUM FAILS AFTER THREE RETRIES, THE
*        LOAD ERROR ROUTINE IS ENTERED, AND THE ERROR 
*        MESSAGE IS DISPLAYED ON THE SCREEN.
* 
 
EXEC     EQU    * 
         LD     IX,PARMS     SET ADDRESS IF LOAD FILE NUMBER
         CALL   LOADF           LOAD TERMINAL RESIDENT. 
         JP     C,RETRY      DISPLAY ERROR MESSAGE IF ERROR 
* 
*** 
         LD     HL,(TTYPE)   GET TERMINAL TYPE. 
         LD     A,H 
         OR     L                 TEST FOR IST2 21/12 BIT 
         JR     NZ,EXEC1     IF NOT AN IST2 21/12 BIT PCN 
         LD     HL,22E5H     FROM 
         LD     DE,0013H     TO 
         LD     BC,8D1H      LEN
         LDIR                MOVE IST2 CHARS DOWN 
* 
EXEC1    EQU    * 
         LD     A,(PARMS) 
         CP     06         IF IST3/2 SHORT ASCII RESIDENT.
         JR     Z,EXEC1A
         CP     08           IF VIKING X
         JR     Z,EXEC1A
         JR     EXEC2        ALL OTHER RESIDENTS. 
 
EXEC1A   EQU    * 
         LD     HL,(BGNADR)  SET THE ENTRY POINT ADDRESS. 
         LD     (BGN.ADR),HL
 
EXEC2    EQU    * 
         LD     IX,PARMS+2   SET ADDRESS OF INTERPRETER NO. 
         CALL   LOADF           LOAD INTERPRETER
         JP     C,RETRY      DISPLAY ERROR MESSAGE IF ERROR 
         LD     A,0D0H
         OUT    (ALARM),A 
* /---   BLOCK      EXEC       00 000   82/04/15  08.53 
         SPACE  4 
**
* 
*        EXIT BOOT LOADER TO ENTRY POINT OF RESIDENT
* 
**
* 
*        INITIALIZE TERMINAL RESIDENT LOAD VARIABLES
* 
EXEC3    EQU    * 
         LD     A,(PARMS) 
         CP     05           TEST FOR IST3 21/12 BIT
         JR     Z,EXEC3A
 
         CP     09           TEST FOR IST3 ASCII GRAPHICS 
         JR     NZ,EXEC4
* 
EXEC3A   EQU    * 
         LD     HL,SAVEI     LOAD FLAG SAVE ADDRESS 
         LD     DE,LOADFLAG  LOAD FLAG ADDRESS
         LD     BC,05 
         LDIR                LOAD RESIDENT FLAGS. 
         XOR    A 
         LD     (M.LDFILE),A   SET FOR LOAD FILE 00.
 
         LD     A,(PARMS) 
         CP     09           TEST FOR ASCII GRAPHICS
         CALL   Z,ACHKSM     GENERATE CHECKSUM FOR ASCII
         JR     EXEC5 
* 
EXEC4    EQU    * 
         CP     03           TEST FOR IST2 21/12 BIT
         JR     NZ,EXEC6     EXIT FOR VIKING X
         LD     HL,(FL.ADR) 
         LD     (HL),01         SET FULL LOAD FLAG
* 
EXEC5    EQU    * 
         LD     HL,(LDS.ADR)
         LD     (HL),-1         SET LOAD SOURCE FLAG
* 
*        FIND ENTRY POINT ADDRESS FOR FLEXIBLE DISK 
*        TO RESIDENT. 
* 
         LD     HL,(BGN.ADR)
         LD     E,(HL)          LOAD LOWER BYTE OF ADDRESS
         INC    HL
         LD     D,(HL)          LOAD UPPER BYTE 
         EX     DE,HL 
         LD     A,(TTYPE)    GET TERMINAL TYPE
         LD     C,A            FOR ASCII RESIDENT.
         JP     (HL)
* 
*        EXIT FOR VIKING X, IST2 ASCII/PLATO, IST3 ASCII/PLA
* 
EXEC6    EQU    * 
         LD     HL,(BGN.ADR)    HL = ADDR OF BLOCK 0 TABLE
         LD     DE,0055H
         ADD    HL,DE 
         LD     E,(HL)
         INC    HL
         LD     D,(HL)       DE = ENTRY POINT ADDRESS 
         EX     DE,HL        HL = ENTRY POINT ADDRESS 
         LD     A,(TTYPE)    GET TERMINAL TYPE
         LD     C,A            FOR ASCII RESIDENT.
         JP     (HL)       GO TO RESIDENT.
* /---   BLOCK      LDERR      00 000   82/04/16  10.30 
         TITLE  RETRY ROUTINE 
* 
*        RETRY LOAD ROUTINE 
* 
RETRY    EQU    * 
         LD     HL,RTYCNT 
         DEC    (HL)    DECREMENT THE RETRY COUNT 
         JP     NZ,EXEC      TRY AGAIN
 
         LD     A,(TTYPE)    GET TERMINAL TYPE
         CP     VIKX         TEST FOR VIKING X
         JR     Z,VLDERR
* 
*        LOAD ERROR ROUTINE 
* 
LDERR    EQU    * 
         LD     DE,MESADR1
         CALL   MESSAGE 
* 
         LD     DE,MESADR2      LOAD SCREEN ADDRESS 
         LD     IX,MES4         LOAD MESSAGE ADDRESS
         CALL   MESSAGE 
* 
LDERR0   EQU    * 
         IN     A,(SYSSTAT)     INPUT STATUS
         AND    08              TEST FOR KEY DATA READY 
         JR     Z,LDERR0
* 
         IN     A,(KBDATA)      INPUT KEY DATA
         AND    7FH 
         CP     NEXT            TEST FOR NEXT KEY 
         LD     A,(TTYPE) 
         LD     C,A          GET TERMINAL TYPE
         JP     Z,BEGIN 
         JR     LDERR0
 
*        LOAD ERROR ROUTINE 
* 
VLDERR   EQU    * 
         PUSH   DE           SAVE MESSAGE ADDRESS 
         LD     DE,1418H   SET TO COL 25, LINE 23 
         CALL   R.SETDE 
         POP    DE           GET MESSAGE ADDRESS
         CALL   VDMSG 
 
         LD     DE,1419H   SET TO COL 25, LINE 30 
         CALL   R.SETDE 
         LD     DE,VMES6      LOAD MESSAGE ADDRESS
         CALL   VDMSG 
* 
VLDERR0  EQU    * 
         IN     A,(UKYBD+ULSTR) 
         AND    KBDR         TEST FOR KEYBOARD DATA 
         JR     Z,VLDERR0 
 
         IN     A,(UKYBD+UDATA)     GET KEY CODE
         XOR    66H          TEST FOR NEXT KEY
         JR     NZ,VLDERR0
 
         LD     DE,1419H
         CALL   R.SETDE 
         LD     DE,VMES0
         CALL   VDMSG         ERASE ERROR MESSAGE 
         LD     A,(TTYPE) 
         LD     C,A          GET TERMINAL TYPE
         JP     BEGIN 
* /---   BLOCK      LOADF      00 000   82/03/18  10.49 
         TITLE  LOAD FILE FROM DISK 
**
* 
*        THIS ROUTINE IS CALLED TO LOAD A FILE FROM 
*        THE FLEXIBLE DISK. 
* 
*        ENTRY; 
*               (IX+0) = LOAD FILE NUMBER 
*               (IX+1) = NUMBER OF ADDITIONAL PARTS 
* 
**
* 
*         STORE RETRY COUNT.
* 
LOADF    EQU    * 
         LD     A,03
         LD     (LRTYCNT),A      LOAD FOR 3 RETRIES IF ERROR
* 
*        LOAD FIRST PART OF THE INTERPRETER.
*        STORE SECTOR SIZE, LOAD ADDRESS, AND NUMBER OF 
*        SECTORS, CALL LOAD ROUTINE, TEST FOR CORRECT 
*        CHECKSUM ON RETURN, (CARRY BIT). 
* 
LOADF1   EQU    * 
         LD     A,(IX+0)          GET FILE NUMBER 
         LD     (RCRDN),A    LOAD RECORD NUMBER FOR INTERP. 
         CALL   FDDLOAD          LOAD NEXT BLOCK
         JR     NC,LOADF2       LOAD SECOND PART
* 
         LD     HL,LRTYCNT      LOAD ADDR OF RETRY COUNT
         DEC    (HL)            DECREMENT COUNT 
         JR     NZ,LOADF1       RELOAD IF NOT ZERO
* 
          LD     IX,MES2     LOAD ADDRESS OF ERROR MSG. 
         SCF                 SET ERROR FLAG 
         RET                   AND EXIT 
* 
*        LOAD SECOND AND THIRD PARTS. 
* 
LOADF2   EQU    * 
         LD     (LDADR),HL      SAVE LOAD ADDRESS 
         LD     A,03
         LD     (LRTYCNT),A     LOAD RETRY COUNT
* 
LOADF3   EQU    * 
         CALL   OUTCS0        LOAD 2ND PART OF INTERPRETER
         JR     C,LOADF4     JUMP IF ERROR
 
         DEC    (IX+1)      DECREMENT ADDITIONAL PART COUNT 
         JR     NZ,LOADF2    LOAD THIRD PART
         RET                 ELSE EXIT
 
LOADF4   EQU    * 
         LD     HL,LRTYCNT      LOAD ADDR OF RETRY COUNT
         DEC    (HL)         DECREMENT COUNT
         JR     NZ,LOADF3       RELOAD IF NOT ZERO
* 
         SCF                 SET ERROR FLAG 
         RET                   AND EXIT.
* /---   BLOCK      FDDLOAD    00 000   82/03/17  11.32 
         TITLE  LOADER SUBROUTINE 
**
* 
*        THIS ROUTINE READS THE CONTROLLER STATUS, TESTS
*        FOR IDLE, SENDS THE READ SECTOR COMMAND AND
*        PARAMETERS. 'WHEN THE STATUS INDICATES THAT THE
*        COMMAND HAS BEEN PROCESSED, THE DATA IS READ AND 
*        STORED INTO THE TERMINAL MEMORY BY SECTORS.
*        'AFTER EACH SECTOR IS STORED, IT IS CHECKSUMED 
*        AND VERIFIED WITH THE SECTOR CHECKSUM FROM THE 
*        DISK CONTROLLER. 
**
 
FDDLOAD  EQU    * 
         LD     D,IDLE          LOAD EXPECTED STATUS
         CALL   WAITC   STATUS CONTROLLER FOR IDLE STATE
         RET    C               RETURN IF ERROR 
* 
         LD     A,RDFILE     LOAD READ FILE COMMAND CODE
         OUT    (DCNTL),A      AND OUTPUT TO DISK CONTLR. 
         LD     D,SCOMD 
         CALL   WAITC   STATUS CONTROLLER FOR IDLE STATE
         RET    C               RETURN IF ERROR 
* 
         LD     A,RDFILE     LOAD READ FILE COMMAND COMPLIM.
         CPL
         OUT    (DCNTL),A      AND OUTPUT . 
         LD     D,IDLE            LOAD EXPECTED STATUS
         CALL   WAITC           STAT COMTROLLER 
         RET    C               RETURN IF ERROR 
* 
         LD     A,(RCRDN)         LOAD RECORD NUMBER
         LD     C,DDATA         LOAD DEVICE FUNC, CODE
         LD     DE,00           INITIALIZE CHECKSUM REG.S 
 
         OUT    (C),A        OUTPUT FILE REQUEST NUMBER 
         LD     B,A 
         RLCA 
         LD     D,A          LOAD PARAMETER 
         LD     A,B 
         RRCA                  CHECKSUM FOR OUTPUT
         LD     E,A 
 
         CALL   DELAY 
         OUT    (C),E           OUTPUT LOWER BYTE CHECKSUM
         CALL   DELAY           WAIT FOR DISK 
         OUT    (C),D           OUTPUT UPPER BYTE CHECKSUM
* 
OUTCS0   EQU    * 
         LD     D,SRXFER
         CALL   WAITC           STATUS CONTROLLER FOR IDLE
         RET    C            EXIT IF ERROR. 
         SPACE  4 
* /---   BLOCK      FDDLOAD    00 000   82/09/20  16.08 
* 
*        READ DATA FROM THE DISK BUFFER 
* 
         LD     C,DDATA         LOAD DISK DATA FUNC. CODE 
         IN     L,(C)        LOAD LOWER ADDRESS BYTE
         NOP
         NOP
 
         IN     H,(C)        LOAD UPPER ADDRESS BYTE
         NOP
         NOP
 
         IN     E,(C)        LOAD LOWER LENGHT BYTE 
         NOP
         NOP
 
         IN     D,(C)        LOAD UPPER LENGHT BYTE 
 
* 
*        IF HL = 0FFFFH, THEN THIS IS A CONTINUED LOAD AND
*        THE ACTUAL LOAD ADDRESS SHOULD BE GOTTEN FROM
*        *LDADR*. 
* 
         LD     A,0FFH
         CP     H 
         JR     NZ,READB     IF NOT A CONTINUED LOAD
         CP     L 
         JR     NZ,READB  @    IF NOT A CONTINUED LOAD
         LD     HL,(LDADR)   CONTINED LOAD ADDRESS
         JR     READB0
READB    EQU    * 
         LD     (BGNADR),HL  SAVE THE STARTING ADDRESS
READB0   EQU    * 
         LD     (LDADR),HL   SAVE THE STARTING ADDRESS
         LD     B,SECTSZ        LOAD DISK SECTOR SIZE 
READB1   EQU    * 
         INI                   LOAD SECTOR DATA TO MEMORY.
         NOP
         JR     NZ,READB1 
* 
READB2   EQU    * 
         IN     A,(C)           INPUT SECTOR CHECKSUM 
         LD     (SAVE),A          AND STORE.
         IN     A,(C) 
         LD     (SAVE+1),A
         CALL   SCHKSM          DO CHECKSUM OF SECTOR DATA
         RET    C               EXIT IF ERROR.
* 
         DEC    DE           DECREMENT BYTE COUNT 
         LD     A,D 
         OR     E            TEST FOR PART COMPLETED
         RET    Z            RETURN IF LOAD COMPLETED 
         JR     READB0           ELSE LOAD NEXT SECTOR
* /---   BLOCK      SUBROUT    00 000   82/09/08  15.21 
         TITLE      SUBROUTINES 
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * 
*        WAITC
*        THIS SUBROUTINE CALLS DELAY AND INPUTS STATUS FROM 
*        THE DISK, COMPARES IT TO A VALUE IN REGISTER D.
*        ENTRY; 
*               D = EXPECTED STATUS 
*        EXIT;
*               NO-CARRY = STATUS EQUALS REGISTER D 
*               CARRY = STATUS NOT EQUALS REGISTER D
*               DE = ADDRESS OF ERROR MESSAGE 
*        CALLS; 
*               DELAY 
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * 
 
WAITC    EQU    * 
         LD     B,40H 
 
WAITC1   EQU    * 
         CALL   DELAY 
         IN     A,(DSTAT) 
         CP     D                  TEST FOR EXPECTED STATUS 
         RET    Z 
* 
         CP     0BEH         TEST FOR SECURED DISK
         JP     Z,READER
* 
         RLCA                   TEST FOR DISK ERROR 
         JR     C,WAITC2     JUMP IF ERROR STATUS 
* 
         DJNZ   WAITC1       LOOP FOR COUNT 
 
WAITC2   EQU    * 
         LD     A,(TTYPE) 
         CP     VIKX         TEST FOR VIKING X
         JR     Z,WAITC3     JUMP IF VIKING X 
 
         SCF
         RET
 
WAITC3   EQU    * 
         LD     DE,VMES2      LOAD ERROR MESSAGE
         SCF                    SET TIME-OUT ERROR
         RET
 
 
* 
*        DELAY OF '/'/ MSECS
* 
DELAY    EQU    * 
         EXX
         LD     HL,1000H        LOAD DELAY COUNT
* 
DELAY1   EQU    * 
         NOP
         NOP
         DEC    HL
         LD     A,H 
         OR     L 
         JR     NZ,DELAY1 
* 
         EXX
         RET
* /---   BLOCK      CHKSUM     00 000   82/04/16  08.33 
         TITLE  CHECKSUM ROUTINES 
* 
*        CHECKSUM SECTOR DATA IN TERMINAL MEMORY
* 
SCHKSM   EQU    * 
         EXX
         LD     B,SECTSZ       LOAD DISK SECTOR SIZE
         LD     DE,0000         CLEAR CHECKSUM REGISTERS
         LD     HL,(LDADR)   LOAD THE STARTING ADDRESS
* 
SCHKSM0  EQU    * 
         CALL   PCHKSM          INCLUDE DATA TO CHECKSUM
         INC    HL              UPDATE DATA POINTER 
         DJNZ   SCHKSM0         LOOP TILL BYTE COUNT ZERO 
* 
         LD     A,(SAVE)        LOAD SECTOR CHECSUM 
         XOR    E               AND TEST. 
         JR     NZ,SCHKSM1       DISK DATA ERROR
         LD     A,(SAVE+1)
         XOR    D 
         JR     NZ,SCHKSM1    IF CHECKSUM IS NOT CORRECT
         EXX                 ELSE RETURN IF 
         RET                   IS COORRECT. 
* 
SCHKSM1  EQU    * 
         EXX
         LD     A,(TTYPE) 
         CP     VIKX         TEST FOR VIKING X
         JR     Z,SCHKSM2 
 
         LD     IX,MES1      LOAD ADDRESS OF ERROR MESSAGE
         SCF
         RET
 
SCHKSM2  EQU    * 
         LD     DE,VMES1      LOAD CHECKSUM ERROR MESSAGE 
         SCF                 SET ERROR INDICATOR
         RET
 
 
* 
*        PARMS TABLE CHECK SUM ROUTINE
*        ENTRY  (HL)    BYTE TO ADD TO CHECK SUM
*               DE      CURRENT CHECK SUM 
*        EXIT   DE      NEW CHECK SUM 
*               CHANGES DE, A 
* 
PCHKSM   EQU    * 
         LD     A,D               LOAD UPPER BYTE 
         XOR    (HL)               INCLUDE PARAMETER
         RLCA                ROTATE LEFT END AROUND 
         LD     D,A             AND SAVE
         LD     A,E               LOAD LOWER BYTE 
         XOR    (HL)               INCLUDE PARAMETER
         RRCA                ROTATE RIGHT END AROUND
         LD     E,A           AND SAVE. 
         RET
* /---   BLOCK      ACHKSM     00 000   82/03/19  16.11 
**
* 
*        ASCII RESIDENT CHECKSUM ROUTINE
*        THE LOADED RAM PROGRAM HAS A CHECKSUM ADDRESS TABLE
*        AS FOLLOWS.
* 
*        (22C8H,22C9H)=FWA   FWA OF CHECKSUM TABLE
*        (22CAH)=CHECKSUM    SET BY LOADER
*        (22CBH)=LOADFLAG    3CH=CODE IS LOADED 
*        (22CCH)=RESETFLAG   3CH=SHORT RESET
*        (22CDH)=MODE        ASCII CONTROLWARE MODE 
*        (22CEH)=LOADINFO    CONTROLWARE LOAD INFORMATION 
*        (22CFH)=RUNINFO     CONTROLWARE RUN INFORMATION
* 
*        (FWA+0,FWA+1)=STARTING ADDRESS OF CODE SEGMENT 1 
*        (FWA+2,FWA+3)=LENGTH IN BYTES OF CODE SEGMENT 1
*        (FWA+4,FWA+5)=STARTING ADDRESS OF CODE SEGMENT 2 
*        (FWA+6,FWA+7)=LENGTH IN BYTES OF CODE SEGMENT 2
*          .
*          .
*        (FWA+4N+0,FWA+4N+1)=00 00   END OF TABLE 
*        (FWA+4N+2,FWA+4N+3)=00 00   (LENGHT =0)
* 
**
* 
**
 
 
ACHKSM   EQU    * 
         LD     C,00         CLEAR CHECKSUM REGISTER
         LD     HL,(BLK0.ADR)   LOAD FWA OF TABLE 
* 
ACHKSM0  EQU    * 
         LD     E,(HL)
         INC    HL
         LD     D,(HL)       DE = FWA OF DATA TO CHECKSUM 
         INC    HL
         LD     B,(HL)       B = LENGTH IN BYTES
         INC    HL
         LD     A,(HL)
         INC    HL
         LD     (SAVE),HL    SAVE TABLE ADDRESS 
         EX     DE,HL        HL = FWA OF DATA 
         LD     E,B          DE = LENGTH OF DATA
         LD     D,A 
* 
         OR     E            TEST IF DONE 
         JR     Z,ACHKSM3    DONE IF LENGTH = 00
* 
ACHKSM1  EQU    * 
         BIT    7,H          ERROR IF ADDRESS TOO LARGE 
         JR     NZ,ACHKSM4
* 
         LD     A,(HL)       GET DATA 
         ADD    A,C          ADD TO CHECKSUM
         LD     C,A 
         INC    HL           INCREMENT ADDRESS
         DEC    DE           DECREMENT BYTE COUNT 
         LD     A,E 
         OR     D            TEST FOR LAST BYTE 
         JR     NZ,ACHKSM1   LOOP TILL COUNT = 00 
* 
         LD     HL,(SAVE)    GET TABLE ADDRESS
         JR     ACHKSM0 
* 
ACHKSM3  EQU    * 
         LD     A,C 
         LD     (CHECKSUM),A      STORE CHECKSUM
         RET                 EXIT 
* 
ACHKSM4  EQU    * 
         LD     IX,MES1      LOAD ERROR MESSAGE ADDRESS 
         SCF                 SET ERROR FLAG 
         RET                 EXIT.
* /---   BLOCK      MESSAGE    00 000   82/09/09  14.51 
         TITLE  SECURITY MESSAGE
* 
*        READ ERROR LOOP
* 
READER   EQU    * 
         LD     A,(TTYPE) 
         CP     02           TEST FOR 721-30 TERMINAL 
         JR     Z,READER2    JUMP IF 721-30 
 
         LD     DE,MESADR6   DISPLAY ERROR MESSAGE. 
         LD     IX,MES14     LOAD MESSAGE ADDRESS 
         CALL   MESSAGE 
         HALT 
 
READER2  EQU    * 
         LD     DE,NUMB+BEGIN-1    ADDRESS OF ERROR CODE. 
         LD     HL,VMES14A-1   ADDRESS OF ERROR MESSAGE 
 
READER3  EQU    * 
         INC    DE
         INC    HL
         LD     A,(DE)
         CP     0FFH         TEST FOR END OF DECODE 
         JR     Z,READER9 
 
         CP     24H          TEST FOR SPACE 
         JR     NZ,READER4
         LD     (HL),20H
         JR     READER3 
 
READER4  EQU    * 
         CP     2BH          TEST FOR COMMA 
         JR     NZ,READER5
         LD     (HL),2CH
         JR     READER3 
 
READER5  EQU    * 
         CP     2CH          TEST FOR PERIOD
         JR     NZ,READER6
         LD     (HL),2EH
         JR     READER3 
 
READER6  EQU    * 
         CP     0AH          TEST FOR NUMERIC 
         JR     NC,READER7
         ADD    A,30H 
         LD     (HL),A
         JR     READER3 
 
READER7  EQU    * 
         ADD    A,37H 
         LD     (HL),A
         JR     READER3 
 
READER9  EQU    * 
         LD     DE,0019H
         CALL   R.SETDE 
         LD     DE,VMES14    LOAD MESSAGE FWA 
         CALL   VDMSG        DISPLAY MESSAGE
         HALT 
* /---   BLOCK      MESSAGE    00 000   82/09/02  14.44 
         TITLE  MESSAGE DISPLAY ROUTINES
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
* 
* CALLABLE ROUTINE TO DISPLAY A FIELD MESSAGE.
* 
* ON ENTRY, DE=FWA OF MESSAGE.
* BC, DE, HL REGISTERS ARE SAVED
* 
*  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *  *
 
VDMSG    EQU    * 
         PUSH   BC
         PUSH   DE
         PUSH   HL
         EX     DE,HL      PUT ADDRESS INTO HL
         CALL   R.DSTRNG   DISPLAY FIELD
         POP    HL
         POP    DE
         POP    BC
         RET
 
 
* 
*        DISPLAYS MESSAGE ON TERMINAL SCREEN
* 
MESSAGE  EQU    * 
         LD     (SAVE),DE    SAVE ADDRESS 
* 
MESSG0   EQU    * 
         LD     A,(IX+0)        LOAD CHARACTER CODE 
         INC    A                AND TEST FOR END OF MESS.
         RET    Z               EXIT IF END 
* 
         INC    A            TEST FOR LINE FEED 
         JR     Z,MESSG1     JUMP FOR LINE FEED 
* 
         LD     H,00            ELSE LOAD HL
         LD     L,(IX+0)         WITH CARACTER CODE 
         ADD    HL,HL           SHIFT FOR 
         ADD    HL,HL            EIGHT BYTE CHARACTERS. 
         ADD    HL,HL 
         LD     BC,CHARSET      LOAD ADDRESS OF CHAR SET
         ADD    HL,BC           ADD FOR ADDRESS OF CHARACTER
         LD     BC,08           LOAD TRANSFER COUNT 
         LDIR                   DISPLAY CHARACTER 
         LD     HL,01F8H        ADJUST THE SCREEN 
         ADD    HL,DE            ADDRESS FOR NEXT CHARACTER 
         EX     DE,HL 
         INC    IX              INCREMENT CHARACTER POINTER 
         JR     MESSG0          DISPLAY NEXT CHARACTER. 
* 
MESSG1   EQU    * 
         LD     HL,0008 
         LD     DE,(SAVE)    LOAD OLD START ADDRESS 
         ADD    HL,DE        CALC. NEW LINE ADDRESS 
         EX     DE,HL 
         INC    IX           INCREMENT CHARACTER POINTER
         JR     MESSAGE 
* /---   BLOCK      VMES       00 000   82/09/02  16.07 
         TITLE  MESSAGES
* 
*        LOAD MESSAGES
* 
*        TURN ON ASCII STRINGS
         CODE   S 
 
*        LOAD MESSAGE 
VMES0    EQU    * 
         TEXT   '7              '7
         TEXT   '7              '7
         DEFB   0FFH
 
*        CHECKSUM ERROR 
VMES1    EQU    * 
         TEXT   '7'C'H'E'C'K'S'U'M 'E'R'R'O'R'7 
         DEFB   0FFH
 
*        DISK READ FAILED 
VMES2    EQU    * 
         TEXT   '7'D'I'S'K 'R'E'A'D 'F'A'I'L'E'D'7
         DEFB   0FFH
* 
*        PRESS NEXT TO TRY AGAIN
VMES6    EQU    * 
         TEXT   '7'P'R'E'S'S 'N'E'X'T 'T'O 'T'R'Y 'A'G'A'I'N'7
         DEFB   0FFH
 
*        LOADING PLATO FROM DISK
VMES11   EQU    * 
         TEXT   '7'L'O'A'D'I'N'G 'T'E'R'M'I'N'A'L 'M'E'M'O'R'Y '7 
         TEXT   '7'F'R'O'M 'D'I'S'K             '7
         DEFB   0FFH
 
*        SECURITY MESSAGE 
VMES14   EQU    * 
         TEXT   '7'T'H'E'R'E 'I'S 'A 'P'R'O'B'L'E'M'7 
         TEXT   '7 'W'I'T'H 'Y'O'U'R 'D'I'S'K, 'P'L'E'A'S'E'7 
         TEXT   '7 'C'A'L'L 'T'H'E 'P'L'A'T'O 'H'O'T'7
         TEXT   '7 'L'I'N'E 'F'O'R 'I'M'M'E'D'I'A'T'E '7
         TEXT   '7'E'V'A'L'U'A'T'I'O'N. 'P'R'O'V'I'D'E'7
         TEXT   '7 'T'H'E 'H'O'T 'L'I'N'E 'W'I'T'H '7 
         TEXT   '7'E'R'R'O'R 'C'O'D'E 'N'U'M'B'E'R 146 '7 
VMES14A  EQU    * 
         TEXT   '7                    '7
         DEFB   0FFH
 
* /---   BLOCK      CHARSET    00 000   82/03/18  08.53 
         TITLE  IST CHARACTER SET 
* 
*        LOADER CHARACTER SET 
* 
CHARSET  EQU    * 
*  0     00 
         HEX    1C,22,22,22,22,22,1C,00 
*  1     01 
         HEX    08,0C,08,08,08,08,3E,00 
*  2     02 
         HEX    1C,22,20,10,08,04,3E,00 
*  3     03 
         HEX    1C,22,20,18,20,22,1C,00 
*  4     04 
         HEX    22,22,22,3E,20,20,20,00 
*  5     05 
         HEX    3E,02,1E,20,20,22,1C,00 
*  6     06 
         HEX    1C,22,02,1A,26,22,1C,00 
*  7     07 
         HEX    3E,20,10,08,04,02,02,00 
*  8     08 
         HEX    1C,22,22,1C,22,22,1C,00 
*  9     09 
         HEX    1C,22,22,3C,20,22,1C,00 
*  'A     0A
         HEX    1C,22,22,3E,22,22,22,00 
*  'B     0B
         HEX    1E,22,22,1E,22,22,1E,00 
*  'C     0C
         HEX    1C,22,02,02,02,22,1C,00 
*  'D     0D
         HEX    1E,22,22,22,22,22,1E,00 
*  'E     0E
         HEX    3E,02,02,1E,02,02,3E,00 
*  'F     0F
         HEX    3E,02,02,1E,02,02,02,00 
*  'G     10
         HEX    1C,22,02,02,32,22,1C,00 
*  'H     11
         HEX    22,22,22,3E,22,22,22,00 
*  'I     12
         HEX    3E,08,08,08,08,08,3E,00 
*  'J     13
         HEX    3C,08,08,08,08,0A,04,00 
*  'K     14
         HEX    22,12,0A,06,0A,12,22,00 
*  'L     15
         HEX    02,02,02,02,02,02,3E,00 
*  'M     16
         HEX    22,36,2A,22,22,22,22,00 
*  'N     17
         HEX    22,26,2A,2A,2A,32,22,00 
*  'O     18
         HEX    1C,22,22,22,22,22,1C,00 
*  'P     19
         HEX    1E,22,22,1E,02,02,02,00 
*  'Q     1A
         HEX    1C,22,22,22,22,32,3C,00 
*  'R     1B
         HEX    1E,22,22,1E,12,22,22,00 
*  'S     1C
         HEX    1C,22,02,1C,20,22,1C,00 
*  'T     1D
         HEX    3E,08,08,08,08,08,08,00 
*  'U     1E
         HEX    22,22,22,22,22,22,1C,00 
*  'V     1F
         HEX    22,22,22,14,14,14,08,00 
*  'W     20
         HEX    22,22,22,22,2A,36,22,00 
*  'X     21
         HEX    22,22,14,08,14,22,22,00 
*  'Y     22
         HEX    22,22,14,08,08,08,08,00 
*  'Z     23
         HEX    3E,20,10,08,04,02,3E,00 
* /---   BLOCK      CHARSET    00 000   82/03/18  12.48 
*  SP    24 
         HEX    00,00,00,00,00,00,00,00 
*        BOX
*        HOR. LINE  25
         HEX    00,00,00,FF,FF,00,00,00 
*        VERT. LINE  26 
         HEX    18,18,18,18,18,18,18,18 
*        UP L CORNER  27
         HEX    00,00,00,F8,F8,18,18,18 
*        UP R CORNER  28
         HEX    00,00,00,1F,1F,18,18,18 
*        LOW L CORNER 
         HEX    18,18,18,F8,F8,00,00,00 
*        LOW R COR
         HEX    18,18,18,1F,1F,00,00,00 
*  COMMA  2B
         HEX    00,00,00,00,00,0C,0C,04 
*  PERIOD  2C 
         HEX    00,00,00,00,00,0C,0C,00 
*  LINE FEED  FE
*  END OF MESSAGE  FF 
* /---   BLOCK      MES        00 000   82/04/21  09.01 
* 
         TITLE  MESSAGES
*        LOAD MESSAGES
* 
 
*        CHECKSUM ERROR 
MES1     EQU    * 
         HEX    0C,11,0E,0C,14,1C,1E,16,24
         HEX    0E,1B,1B,18,1B,24,24,24,FF
 
*        DISK READ FAILED 
MES2     EQU    * 
         HEX    0D,12,1C,14,24
         HEX    1B,0E,0A,0D,24
         HEX    0F,0A,12,15,0E,0D,24,FF 
 
*        LOADING PLATO FROM DISK
MES3     EQU    * 
         HEX    15,18,0A,0D,12,17,10,24 
         HEX    19,15,0A,1D,18,24 
         HEX    0F,1B,18,16,24
         HEX    0D,12,1C,14,24,FF 
 
*        PRESS NEXT TO TRY AGAIN
MES4     EQU    * 
         HEX    19,1B,0E,1C,1C,24 
         HEX    17,0E,21,1D,24
         HEX    1D,18,24
         HEX    1D,1B,22,24 
         HEX    0A,10,0A,12,17,24,FF
* /---   BLOCK      MES        00 000   82/04/21  08.25 
 
*        IF YOU ARE GOING TO USE THIS TERMINAL AS A PLATO 
*        OR MICRO PLATO STATION PRESS OR TOUCH P TO LOAD
MES5     EQU    * 
         HEX    12,0F,24,22,18,1E,24
         HEX    0A,1B,0E,24,10,18,12,17,10,24 
         HEX    1D,18,24,1E,1C,0E,24
         HEX    1D,11,12,1C,24
         HEX    1D,0E,1B,16,12,17,0A,15,FE,FE 
         HEX    0A,1C,24,0A,24
         HEX    19,15,0A,1D,18,24 
         HEX    18,1B,24,16,12,0C,1B,18,24
         HEX    19,15,0A,1D,18,24 
         HEX    1C,1D,0A,1D,12,18,17,2B,FE,FE 
         HEX    19,1B,0E,1C,1C,24 
         HEX    18,1B,24,1D,18,1E,0C,11,24
         HEX    19,24 
         HEX    1D,18,24
         HEX    15,18,0A,0D,2C,FF 
 
*        IF YOU ARE GOING TO USE THIS TERMINAL TO 
*        COMMUNICATE TO AN ASCII PLATO SYSTEM, PRESS OR 
*        TOUCH A TO LOAD. 
MES6     EQU    * 
         HEX    12,0F,24,22,18,1E,24
         HEX    0A,1B,0E,24,10,18,12,17,10,24 
         HEX    1D,18,24,1E,1C,0E,24
         HEX    1D,11,12,1C,24
         HEX    1D,0E,1B,16,12,17,0A,15,FE,FE 
         HEX    1D,18,24
         HEX    0C,18,16,16,1E,17,12,0C,0A,1D,0E,24 
         HEX    1D,18,24,0A,17,24 
         HEX    0A,1C,0C,12,12,24 
         HEX    19,15,0A,1D,18,24 
         HEX    1C,22,1C,1D,0E,16,2B,FE,FE
         HEX    19,1B,0E,1C,1C,24 
         HEX    18,1B,24,1D,18,1E,0C,11,24
         HEX    0A,24 
         HEX    1D,18,24
         HEX    15,18,0A,0D,2C,FF 
 
*        IF YOU ARE GOING TO USE THIS TERMINAL TO 
*        COMMUNICATE TO AN ASCII GRAPHICS SYSTEM, PRESS 
*        OR TOUCH G TO LOAD.
MES7     EQU    * 
         HEX    12,0F,24,22,18,1E,24
         HEX    0A,1B,0E,24,10,18,12,17,10,24 
         HEX    1D,18,24,1E,1C,0E,24
         HEX    1D,11,12,1C,24
         HEX    1D,0E,1B,16,12,17,0A,15,FE,FE 
         HEX    1D,18,24
         HEX    0C,18,16,16,1E,17,12,0C,0A,1D,0E,24 
         HEX    1D,18,24,0A,17,24 
         HEX    0A,1C,0C,12,12,24 
         HEX    10,1B,0A,19,11,12,0C,1C,24
         HEX    1C,22,1C,1D,0E,16,2B,FE,FE
         HEX    19,1B,0E,1C,1C,24 
         HEX    18,1B,24,1D,18,1E,0C,11,24
         HEX    10,24 
         HEX    1D,18,24
         HEX    15,18,0A,0D,2C,FF 
* /---   BLOCK      MES        00 000   82/09/09  14.17 
 
*        LOADING PLATO FROM DISK
MES8     EQU    * 
         HEX    15,18,0A,0D,12,17,10,24 
         HEX    0A,1C,0C,12,12,24 
         HEX    19,15,0A,1D,18,24 
         HEX    0F,1B,18,16,24
         HEX    0D,12,1C,14,24,FF 
 
*        LOADING PLATO FROM DISK
MES9     EQU    * 
         HEX    15,18,0A,0D,12,17,10,24 
         HEX    19,15,0A,1D,18,24 
         HEX    10,1B,0A,19,11,12,0C,1C,24
         HEX    0F,1B,18,16,24
         HEX    0D,12,1C,14,24,FF 
 
* BIG G 
MES11    EQU    * 
         HEX    27,25,28,FE,26,10,26,FE,29,25,2A,FF 
 
* BIG A 
MES12    EQU    * 
         HEX    27,25,28,FE,26,19,26,FE,29,25,2A,FF 
 
* BIG P 
MES13    EQU    * 
         HEX    27,25,28,FE,26,0A,26,FE,29,25,2A,FF 
 
*        THERE IS A PROBLEM 
MES14    EQU    * 
         HEX    FE,1D,11,0E,1B,0E,24,12,1C,24,0A,24 
         HEX    19,1B,18,0B,15,0E,16,24,20,12,1D
         HEX    11,24,22,18,1E,1B,24,0D,12,1C,14
         HEX    2B,24,19,15,0E,0A,1C,0E,24,0C,0A
         HEX    15,15,24,1D,11,0E,FE,FE,19,15,0A,1D 
         HEX    18,24,11,18,1D,24,15,12,17,0E,24
         HEX    0F,18,1B,24,12,16,16,0E,0D,12,0A
         HEX    1D,0E,24,0E,1F,0A,15,1E,0A,1D,12
         HEX    18,17,2C,24,19,1B,18,1F,12,0D,0E
         HEX    FE,FE,1D,11,0E,24,11,18,1D,24,15,12 
         HEX    17,0E,24,1D,11,0E,24,0E,1B,1B,18
         HEX    1B,24,0C,18,0D,0E,24,17,1E,16,0B
         HEX    0E,1B,24,01,04,06,24
 
NUMB      EQU    *-BEGIN+6
         HEX    00,00,00,00,00,00,00,00,00,00,24
         HEX    00,00,00,00,00,00,00,00,00,00,FF,FF,FF
 
ENDLDR    EQU    *-BEGIN+6
* /---   BLOCK      END        00 000   82/05/27  08.44 
         TITLE      LOADER VARIABLES
* 
*        PARAMETER TABLE
*               INTIALIZED TO DRIVE 0, SIDE 0, TRACK 0, 
*               SECTOR 00, ONE SECTOR, SINGLE DENSITY.
* 
PARMS    EQU    * 
DRIVE    EQU    PARMS           DRIVE NUMBER, 0 OR 1
SIDE     EQU    DRIVE+1         DISK SIDE, 0 OR 1 
TRACK    EQU    SIDE+1          TRACK NUMBER, 00 TO 76
SECTOR   EQU    TRACK+1         STARTING SECTOR, 00 TO 26 
NSECT    EQU    SECTOR+1        NUMBER OF SECTOR TO PROCESS 
DENSITY  EQU    NSECT+1         SINGLE OR DOUBLE DENSITY
* 
*        FLAGS AND VARIABLES
* 
RCRDN    EQU    DENSITY+1    REQUESTED DISK RECORD NUMDER 
SAVE     EQU    RCRDN+1         EIGHT BYTE SCRATCH PAD
CMD      EQU    SAVE+8          COMMAND TO BE USED
NSEC     EQU    CMD+1           NUMBER OF SECTORS TO PROCESS
LDADR    EQU    NSEC+1          TERMINAL MEMORY ADDRESS 
RTYCNT   EQU    LDADR+2         RETRY COUNT 
LRTYCNT  EQU    RTYCNT+1        LOAD RETRY COUNT
* 
CHRLWA   EQU    LRTYCNT+1       CHARACTER SET LWA 
RESLWA   EQU    CHRLWA+2        RESIDENT LWA
INTLWA   EQU    RESLWA+2        INTERPRETER LWA 
ASCLWA   EQU    INTLWA+2        ASCII RESIDENT LWA
* 
BGN.ADR  EQU    ASCLWA+2        ADDRESS OF RES. ADDRESS 
BLK0.ADR EQU    BGN.ADR+2       BLOCK 0 FWA 
M0.ADR   EQU    BLK0.ADR+2      CHAR SET FWA
LDS.ADR  EQU    M0.ADR+2        LOAD SOURCE FLAG ADDRESS
FL.ADR   EQU    LDS.ADR+2       FULL LOAD FLAG ADDRESS
LDFG     EQU    FL.ADR+2        LOAD FLAG 
TTYPE    EQU    LDFG+2          TERMINAL TYPE, 0=IST2,1=IST3
*                            TTYPE+1, 0=21/12 BIT, 80H=ASCII
SAVEI    EQU    TTYPE+2          SAVE ROM  LOADER VARIBLES
BGNADR   EQU    SAVEI+5 
OPFLG    EQU    BGNADR+2
         END