be_chti/1.1/Src/gen_signal.s
2020-03-16 14:35:31 +01:00

30 lines
No EOL
491 B
ArmAsm

thumb
area moncode, code, readonly
GPIOB_BSRR equ 0x40010C10 ; Bit Set/Reset register
extern current_value
export timer_callback
timer_callback proc
ldr r2, =current_value
ldr r0, [r2]
ldr r3, =GPIOB_BSRR
cbnz r0, zero
; mise a 1 de PB1
mov r1, #0x00000002
str r1, [r3]
mov r1, #1
str r1, [r2]
bx lr
; mise a 0 de PB1
zero mov r1, #0x00020000
str r1, [r3]
mov r1, #0
str r1, [r2]
bx lr
endp
end
; N.B. le registre BSRR est write-only, on ne peut pas le relire