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; pb3_test.psm
; A very simple kcasm test for PacoBlaze3
; We load some data to registers and do some loops while
; one register is modified when an interrupt occurs
; register definitions
register r0, 0 ; alias register #0 (s0) as r0
register r1, 1 ; alias register #1 (s1) as r1
register ic, 15 ; counter register used by our interrupt service routine (isr)
; constant definitions
constant binary, %1001 ; a binary value
constant octal, @77 ; an octal value
constant decimal, &123 ; a decimal value
constant hexadecimal, $ca ; an hexadecimal value
constant character, 'a' ; a character value
; our entry point
start:
load r0, binary ; load r0 with the 'binary' value
load r1, $fe ; load r1 with $fe in hex
load ic, 0 ; set up the initial value of the interrupt counter register
load s2, 0 ; clear register #2
add s2, r0 ; add register #0 to register #2
addcy s2, r1 ; add with carry register #1 to register #2
interrupt enable ; enable interrupt
; our first loop
loop:
_loop: ; 'loop' alias, same program counter
input s3, s2 ; read into register #3 with port value at id in register #2
subcy s3, 1 ; substract 1 with carry
output s3, s2 ; write back register #3 value
jump c, loop_1 ; jump if carry to 'loop_1'
srx s2 ; shift-right extended register #2
loop_1: slx s3 ; shift-left extended register #3
call func ; call function 'func'
jump loop ; inconditional jump back to 'loop'
func: ; a function
add s0, hexadecimal ; add 'hexadecimal' value to register #0
subcy s0, decimal ; substract with carry 'decimal' to register #0
return ; return back
; our interrupt service routine
isr:
add ic, 1 ; increment register ic (#15)
returni enable ; return from interrupt with interrupts enabled
int: address $3ff ; the interrupt entry point
jump isr ; jump to 'isr'