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Hello, I'm working on the XC164X µc and I've a question concerning the storage of registers in stack when interrupt occur.
The function is written in c language
void ItFunc (void) interrupt 14 { funcCode (); }
The pre-processor code is as follow:
ItFunc PROC INTERRUPT = 14 GLOBAL ItFunc ; FUNCTION ItFunc (BEGIN RMASK = @0x3FFF)
SCXT DPP3,#3
PUSH DPP0
SCXT MDC,#16
PUSH MDH
PUSH MDL
MOV [-R0],R1
MOV [-R0],R2
MOV [-R0],R3
MOV [-R0],R4
MOV [-R0],R5
MOV [-R0],R6
MOV [-R0],R7
MOV [-R0],R8
MOV [-R0],R9
MOV [-R0],R10
MOV [-R0],R11
MOV [-R0],R12
; line 234: funcCode ();
CALL funcCode
?C0005:
MOV R12,[R0+]
MOV R11,[R0+]
MOV R10,[R0+]
MOV R9,[R0+]
MOV R8,[R0+]
MOV R7,[R0+]
MOV R6,[R0+]
MOV R5,[R0+]
MOV R4,[R0+]
MOV R3,[R0+]
MOV R2,[R0+]
MOV R1,[R0+]
POP MDL
POP MDH
POP MDC
POP DPP0
POP DPP3
RETI
; FUNCTION ItFunc (END RMASK = @0x3FFF)
ItFunc ENDP
?PR?BS_TST ENDS
As shown in this pre-processor code, we use the register R0 to save the registers R1—R12. I'd like to store the registers using the instruction PUSH R1. How can I do this? Which directive could I use that the compiler store the registers in stack using the instruction "PUSH R1" and not using "MOV [-R0], R1"
Thanks
No, the compiler really do decide what to do. We write source code to inform it what we want solved, and we use directives to give it hints about how to solve it.
If it was you who decided what to do, then you wouldn't need to buy the compiler, since you would not have any need for it. The way you decide what to do, is by writing the program in assembler.