Type ASSEMBLE
Source Lines : 197
Fixes Applied : 0
Most Recent Version : Thursday, December 7, 1978
Last Fix ID : [Unmodified]
Module
DMTEXT
Function
THE DMTEXT MODULE IS THE MSUP EXTERNAL INTERRUPT
HANDLER. DMTEXT RECEIVES CONTROL DIRECTLY ON AN
EXTERNAL INTERRUPT AND SAVES THE STATUS OF THE
EXECUTING TASK IF ONE WAS INTERRUPTED.
Attributes
REUSABLE, EXECUTABLE DISABLED ONLY
Operation
IF A TASK WAS EXECUTING AT THE TIME OF THE INTERRUPT, IT IS
SUSPENDED. IF THERE HAVE BEEN NO REQUESTS FOR
EXTERNAL INTERRUPT ASYNCHRONOUS EXITS, EXIT IS MADE TO
THE DISPATCHER. IF THERE HAVE BEEN REQUESTS MADE, THE
EXTERNAL INTERRUPT CODE IS EXAMINED. ONLY THE FOLLOWING
INTERRUPT CODES ARE SERVICED, ALL OTHERS RESULT IN AN
IMMEDIATE EXIT TO THE DISPATCHER:
X'1004' - CLOCK COMPARATOR
THE QUEUE IS SCANNED TO FIND THE ASYNCHRONOUS QUEUE
ELEMENT WHICH CORRESPONDS TO THIS INTERRUPT.
FOR CLOCK COMPARATOR INTERRUPTS, THE FIRST ELEMENT SHOULD
SATISFY THE SEARCH, SINCE THEY ARE QUEUED IN ASSENDING ORDER
WITH THE FIRST ELEMENT BEING THE ACTIVE ONE.
THE QUEUE ELEMENT IS DEQUEUED AND RETURNED TO THE POOL.
IF THERE IS ANOTHER CLOCK COMPARATOR QUEUE ELEMENT BEHIND
IT, IT IS MADE THE ACTIVE ELEMENT AND THE CLOCK COMPARATOR
IS SET FOR ITS VALUE; IF THERE ARE NO MORE CLOCK COMPARATOR
REQUESTS BEHIND IT, THE CLOCK COMPARATOR IS SET FOR ALL
HEX F'S. IN EITHER CASE, THEREAFTER THE USER TASK EXIT
IS TAKEN
AFTER THE EXIT HAS BEEN TAKEN, RETURN IS MADE TO
THE DISPATCHER
Calls to Other Routines
DMTDSP - TO RESUME DISPATCHED PROCESSING