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- /*
- * picasm -- pic12bit.c
- *
- * Timo Rossi <trossi@iki.fi>
- *
- */
-
- #include <stdio.h>
-
- #include "picasm.h"
-
- /*
- * Assemble 12-bit PIC code
- *
- */
- int
- assemble_12bit_mnemonic(int op)
- {
- long val;
- struct symbol *sym;
- char *cp;
- int t, symtype;
-
- switch(op) {
- case KW_ANDLW:
- case KW_IORLW:
- case KW_XORLW:
- val = get_expression();
- if(expr_error)
- return FAIL;
- if(val < -0x80 || val > 0xff)
- error(1, "8-bit literal out of range");
- val &= 0xff; /* this assumes 2-complement negative numbers */
- switch(op) {
- case KW_ANDLW: gen_code(0xe00 | val); break;
- case KW_IORLW: gen_code(0xd00 | val); break;
- case KW_XORLW: gen_code(0xf00 | val); break;
- }
- break;
-
- case KW_MOVLW:
- if(gen_byte_c(0xc00) != OK)
- return FAIL;
- break;
-
- case KW_ADDWF:
- case KW_SUBWF:
- case KW_ANDWF:
- case KW_IORWF:
- case KW_XORWF:
- case KW_COMF:
- case KW_DECF:
- case KW_INCF:
- case KW_MOVF:
- case KW_DECFSZ:
- case KW_INCFSZ:
- case KW_RLF:
- case KW_RRF:
- case KW_SWAPF:
- val = get_expression();
- if(expr_error)
- return FAIL;
- if(val < 0 || val > 0x1f)
- error(0, "Register file address out of range");
- t = 1;
- if(token_type == TOK_COMMA) {
- get_token();
- t = get_expression();
- if(expr_error)
- return FAIL;
- } else {
- if(warnlevel > 0)
- warning("Destination speficier omitted");
- }
- val = (val & 0x1f) | (t != 0 ? 0x20 : 0);
- switch(op) {
- case KW_ADDWF: gen_code(0x1c0 | val); break;
- case KW_SUBWF: gen_code(0x080 | val); break;
- case KW_ANDWF: gen_code(0x140 | val); break;
- case KW_IORWF: gen_code(0x100 | val); break;
- case KW_XORWF: gen_code(0x180 | val); break;
- case KW_COMF: gen_code(0x240 | val); break;
- case KW_DECF: gen_code(0x0c0 | val); break;
- case KW_INCF: gen_code(0x280 | val); break;
- case KW_MOVF: gen_code(0x200 | val); break;
- case KW_DECFSZ: gen_code(0x2c0 | val); break;
- case KW_INCFSZ: gen_code(0x3c0 | val); break;
- case KW_RLF: gen_code(0x340 | val); break;
- case KW_RRF: gen_code(0x300 | val); break;
- case KW_SWAPF: gen_code(0x380 | val); break;
- }
- break;
-
- case KW_CLRF:
- case KW_MOVWF:
- val = get_expression();
- if(expr_error)
- return FAIL;
- if(val < 0 || val > 0x1f)
- error(0, "Register file address out of range");
- switch(op) {
- case KW_CLRF: gen_code(0x060 | val); break;
- case KW_MOVWF: gen_code(0x020 | val); break;
- }
- break;
-
- case KW_BCF:
- case KW_BSF:
- case KW_BTFSC:
- case KW_BTFSS:
- val = get_expression();
- if(expr_error)
- return FAIL;
- if(val < 0 || val > 0x1f)
- error(0, "Register file address out of range");
- if(token_type != TOK_COMMA) {
- error(1, "',' expected");
- return FAIL;
- }
- get_token();
- t = get_expression();
- if(expr_error)
- return FAIL;
- if(t < 0 || t > 7) {
- error(0, "Bit number out of range");
- }
- val |= (t << 5);
- switch(op) {
- case KW_BCF: gen_code(0x400 | val); break;
- case KW_BSF: gen_code(0x500 | val); break;
- case KW_BTFSC: gen_code(0x600 | val); break;
- case KW_BTFSS: gen_code(0x700 | val); break;
- }
- break;
-
- case KW_CALL:
- case KW_GOTO:
- t = 0;
- if(token_type == TOK_IDENTIFIER || token_type == TOK_LOCAL_ID) {
- symtype =
- (token_type == TOK_IDENTIFIER ? SYMTAB_GLOBAL : SYMTAB_LOCAL);
-
- if(symtype == SYMTAB_LOCAL && local_level == 0) {
- error(1, "Local symbol outside a LOCAL block");
- return FAIL;
- }
-
- sym = lookup_symbol(token_string, symtype);
- if(sym == NULL || sym->type == SYM_FORWARD) {
- if(sym == NULL) {
- sym = add_symbol(token_string, symtype);
- sym->type = SYM_FORWARD;
- }
-
- val = 0;
- add_patch(symtype, sym,
- (op == KW_CALL ? PATCH8 : PATCH9));
- t = 1;
- get_token();
- goto gen_goto_call;
- }
- }
-
- val = get_expression();
- if(expr_error)
- return FAIL;
-
- if(val < 0 || val >= prog_mem_size)
- error(0, "GOTO/CALL address out of range");
-
- if(op == KW_CALL && (val & 0x100) != 0)
- error(0, "CALL address in upper half of a page");
-
- gen_goto_call:
- switch(op) {
- case KW_CALL: gen_code(0x900 | (val & 0xff)); break;
- case KW_GOTO: gen_code(0xa00 | (val & 0x1ff)); break;
- }
- if(t)
- list_flags |= LIST_FORWARD;
- break;
-
- case KW_TRIS:
- t = get_expression();
- if(expr_error)
- return FAIL;
- if(t != 5 && t != 6 && t != 7)
- error(0, "Invalid register address for TRIS");
- gen_code(0x000 | t);
- break;
-
- /*
- * RETLW allows multiple parameters/strings, for generating lookup tables
- */
- case KW_RETLW:
- for(;;) {
- if(token_type == TOK_STRCONST) {
- for(cp = token_string; *cp != '\0'; cp++)
- gen_code(0x800 | (int)((unsigned char)(*cp)));
- get_token();
- } else {
- if(gen_byte_c(0x800) != OK)
- return FAIL;
- }
-
- if(token_type != TOK_COMMA)
- break;
-
- get_token();
- }
- break;
-
- case KW_NOP:
- gen_code(0x000);
- break;
-
- case KW_CLRW:
- gen_code(0x040);
- break;
-
- case KW_OPTION:
- gen_code(0x002);
- break;
-
- case KW_SLEEP:
- gen_code(0x003);
- break;
-
- case KW_CLRWDT:
- gen_code(0x004);
- break;
-
- case KW_RETURN:
- case KW_RETFIE:
- case KW_ADDLW:
- case KW_SUBLW:
- error(1, "Unimplemented instruction for PIC%s", pic_type->name);
- return FAIL;
-
- default:
- error(1, "Syntax error");
- return FAIL;
- }
-
- return OK;
- }
-
-