User manual

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SYSTEM CALLS
M68CPU32BUG/D REV 1 5-26
.TM_STR0 Start Timer at T=0 .TM_STR0
MOVE.L #$00000002,-(A7)
Reset the timer to zero and start it with the default control
SYSCALL .TM_STR0
value (PICR) and a period value (PITR) of $0002 (=244
usec/interrupt).
MOVE.L #$054400A0,-(A7)
Reset the timer to zero and start
it with the control value
SYSCALL .TM_STR0
(PICR) of $0544 (level 5, vector 68 = $44) and a period
value (PITR) of $00A0 (=19.5 msec/interrupt).
SYSTEM CALLS
M68CPU32BUG/D REV 1 5-23
.TM_INI Timer Initialization .TM_INI
5.2.19 Timer Initialization
SYSCALL .TM_INI
TRAP CODE: $0040
Use .TM_INI to initialize the MCU periodic interrupt timer. .TM_INI stops the timer and then
initializes it. .TM_INI does not restart the timer; use .TM_STR0 to restart the timer. Timing is
accomplished by counting the number of interrupt pulses generated. The default interrupt pulse
frequency is 125 milliseconds. Use this routine the first time the timer functions are used.
Entry Conditions:
No arguments required.
Exit Conditions Different From Entry:
Periodic interrupt timer is stopped (no interrupts) and initialized for future
operation.
EXAMPLE
SYSCALL .TM_INI
Initialize timer
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