errori la cod asm in hi-tech

[daniel_smd]

Vreau sa fac o functie rapida de checksum, asa ca m-am inspirat din forumul microchip

http://www.microchip.com/forums/fb.ashx?m=367982

 

Problema e, ca in Hi-tech cand introduc codul

unsigned char  Checksum(unsigned char *data, unsigned char length) {     unsigned char result = 0;     unsigned int l = length - 1;     asm volatile ( "repeat %2\nsub.b %0,[%1++],%0"                : "+r" (result), "+r" (data)           : "r" (l)           : "_RCOUNT");     return result; }

, primesc erori:

130.5 "(" expected

130.5 string expected

130.5 ")" expected

130.5 ";" expected

Linia 130 este cea cu asm volatile.....

 

 

Am incercat si _asm volatile si imi da eroarea : 130.1 expression syntax

Eu nu stiu limbajul assambler , daca are cineva idee unde este greseala sau cum ar trebui sa arate codul... ii sunt recunoscator

[Liviu M]

Citat din manualul unei variante de picc (pentru varianta pe care o ai tu cauta manualul in subdirectorul doc)

3.13.2 #asm, #endasm and asm()PIC MCU instructions may also be directly embedded “in-line” into C code using thedirectives #asm, #endasm or the statement asm();.The #asm and #endasm directives are used to start and end a block of assemblyinstructions which are to be embedded into the assembly output of the code generator.The #asm block is not syntactically part of the C program, and thus it does not obeynormal C flow-of-control rules. This means that you should not use this form of in-lineassembly inside C constructs like if(), while() and for() statements. Howeverthis is the easiest means of adding multiple assembly instructions.The asm() statement is used to, typically, embed a single assembler instruction. Thisform looks and behaves like a C statement. Only one assembly instruction may beencapsulated within each asm() statement. You can specify more than one assemblyinstruction inside one asm() statement by separating the instructions with a \n character,(e.g. asm("movlw 55\nmovwf _x");) although code will be more readable ifyou one place one instruction in each statement and use multiple statements.You may use the asm(" ") form of in-line assembly at any point in the C source codeas it will correctly interact with all C flow-of-control structures.The following example shows both methods used:

unsigned int var;void main(void){var = 1;#asm // like this...BCF 0,3BANKSEL(_var)RLF (_var)&07fhRLF (_var+1)&07fh#endasm// do it again the other way...asm("BCF 0,3" );asm("BANKSEL _fvar");asm("RLF (_var)&07fh" );asm("RLF (_var+1)&07fh" );}

When using in-line assembler code, great care must be taken to avoid interacting withcompiler-generated code. The code generator cannot scan the assembler code for registerusage and so will remain unaware if registers are clobbered or used by the assemblycode.