ST ST7 Series, Руководство пользователя

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7 - Debugger and PROM Programmer Tutorial for ST72251
ld X, {Ad4} ; MSB address Task
push X ; Written at top of stack
ld A, S
ld ImStack3, A
; Remember position of stack pointer
ld A, #org2 ; Top of stack for task 2
ld S, A
ld X, {Ad3}
; LSB address Task
push X
ld X, {Ad2}
; MSB address Task
push X ; Written at top of stack
ld A, S
ld ImStack2, A
; Remember position of stack pointer
ld A, #org1 ; Top of stack for task 1
ld S, A
ld X, {Ad1}
; LSB address Task
push X
ld X, AddrTasks
; MSB address Task
push X ; Written at top of stack
ld A, S
ld ImStack1, A
; Remember position of stack pointer
clr Permut ; Set task counter to first
ret ; Jump to first task
; Yield
; =====
Yield:
ld A, #watch ; Loading the watchdog
ld wdgr, A
ld X, Permut
; To select the element where to save
ld A, S ; The stack pointer of the current task
ld (ImStack1,X), A
ld A, X
inc A
; Increment number of task
and A, #3 ; If last, go to first
ld Permut, A
ld X, A
ld A, (ImStack1,X)
; Get next stack pointer
ld S, A
ret
END