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55 lines
1.1 KiB
C++
55 lines
1.1 KiB
C++
// In fastcpu ino
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extern unsigned short PC;
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extern unsigned char X, Y;
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// Addressing Modes
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unsigned short inline a_abs() {
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PC += 2;
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return read16(PC-2);
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}
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unsigned short inline a_absx() {
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PC += 2;
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return (read16(PC-2) + (unsigned short)X);
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}
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unsigned short inline a_absy() {
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PC += 2;
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return (read16(PC-2) + (unsigned short)Y);
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}
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unsigned short inline a_imm() {
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return PC++;
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}
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//ignore page wrap bug
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unsigned short inline a_ind() {
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PC += 2;
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return read16(read16(PC-2));
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}
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unsigned short inline a_indx() {
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return read16(((unsigned short)read8(PC++) + (unsigned short)X)&0xFF);
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}
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unsigned short inline a_indy() {
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return read16(((unsigned short)read8(PC++) + (unsigned short)Y)&0xFF);
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}
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unsigned short inline a_rel() {
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unsigned short addr = (unsigned short)read8(PC++);
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return addr | ((addr&0x80)?0xFF00:0x0000);
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}
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unsigned short inline a_zpg() {
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return (unsigned short)read8(PC++);
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}
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unsigned short inline a_zpgx() {
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return ((unsigned short)read8(PC++) + (unsigned short)X)&0xFF;
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}
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unsigned short inline a_zpgy() {
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return ((unsigned short)read8(PC++) + (unsigned short)Y)&0xFF;
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}
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