Hi, I'm porting some C code written for Hitech PIC C Compiler; my target is AVR. unfortunately, there are some asm directives which I don't understand (they are probably related to PIC architecturee, which I don't know):
rlf _aux,w rlf _Buffer,f rlf _Buffer+1,f rlf _Buffer+2,f rlf _Buffer+3,F
Buffer is a 4-bytes vector, aux is an unsigned char variable; I guess w,f and F are PIC registers; can anyone point to me some asm directives list for PIC or just give me some hint? thanks
Those are not directives, they are assembly instructions.
Download a datasheet for the PIC you are porting it from and you'll get a concise summary of the instruction set and an explanation of the architecture. If you need more (you shouldn't), download the approprate reference manual.
rlf = rotate left f through carry
w and f determine the destination of the instruction-- w is the accumulator of the PIC, f is a ram location ('file register'). It's a single bit in the instruction opcode.
Note that the fragment you've quoted above does not modify _aux, only the 4 bytes of _Buffer.._Buffer+3 (it left shifts bit 7 of _aux into the 32 bit buffer, and bit 7 of _Buffer+3 ends up in the carry).
Best regards, Spehro Pefhany
In C it could be expressed as:
unsigned char aux; unsigned char Buffer[4];
*(long *)BufferHi, thanks to everyboy, I think I've found equivalent AVR instructions; also, I've translated them in C; in the next days I'll see if my Keeloq decoder works...
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