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|
list p=16f84
;; The purpose of this program is to test gpsim's capability to simulate
;; the PIC's stack.
;;
;; Start gpsim:
;; $ gpsim
;; then load the Startup command file 'stack_test.stc':
;; gpsim> load c stack_test.stc
;;
;; OR
;;
;; invoke gpsim with the command file
;; $ gpsim -c stack_test.stc
;;
;; OR
;;
;; invoke the simualtion from the Makefile:
;; make sim
;; In all cases, the stimulus file will load the simulation
;; file and create the stimuli. In the Makefile case, the
;; simulation file will be (re)created if the .asm has been
;; been changed.
;;
;;
include "p16f84.inc"
cblock 0x20
temp1
temp2
temp3
endc
org 0
goto start
org 4
start
clrf temp1 ; a counter
clrf temp2 ; a flag keeping track of the state of port b
init_tasks
goto Task_0_init
init_done
return
begin
;; Count the rising edges on portb bit 0
movf PORTB,w
xorwf temp2,w
xorwf temp2,f
andwf temp2,w
andlw 1
skpz
incf temp1,f
goto begin
Task_0_init:
call Task_1_init
Task_0:
return
Task_1_init:
call Task_2_init
Task_1:
btfsc PORTB,0
goto t1b
call $+1
t1a
movlw 2
return
t1b
movlw 3
return
Task_2_init:
call Task_3_init
Task_2:
return
Task_3_init:
call Task_4_init
Task_3:
return
Task_4_init:
call Task_5_init
Task_4:
return
Task_5_init:
call Task_6_init
Task_5:
return
Task_6_init:
call Task_7_init
Task_6:
return
Task_7_init:
call init_done
Task_7:
return
end
|
