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Avoid duplication of CIA select test.

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Thomas Harte 2021-10-30 12:05:18 -07:00
parent 02c88e6826
commit 16f31cab6a
1 changed files with 7 additions and 5 deletions
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12
Machines/Amiga/Amiga.cpp
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@ -125,18 +125,20 @@ class ConcreteMachine:
// directly to the chip enables.
if((address & 0xe0'0000) == 0xa0'0000) {
const int reg = address >> 8;
const bool select_a = !(address & 0x1000);
const bool select_b = !(address & 0x2000);
if(cycle.operation & Microcycle::Read) {
uint16_t result = 0xffff;
if(!(address & 0x1000)) result &= 0xff00 | (chipset_.cia_a.read(reg) << 0);
if(!(address & 0x2000)) result &= 0x00ff | (chipset_.cia_b.read(reg) << 8);
if(select_a) result &= 0xff00 | (chipset_.cia_a.read(reg) << 0);
if(select_b) result &= 0x00ff | (chipset_.cia_b.read(reg) << 8);
cycle.set_value16(result);
} else {
if(!(address & 0x1000)) chipset_.cia_a.write(reg, cycle.value8_low());
if(!(address & 0x2000)) chipset_.cia_b.write(reg, cycle.value8_high());
if(select_a) chipset_.cia_a.write(reg, cycle.value8_low());
if(select_b) chipset_.cia_b.write(reg, cycle.value8_high());
}
// LOG("CIA " << (((address >> 12) & 3)^3) << " " << (cycle.operation & Microcycle::Read ? "read " : "write ") << std::dec << (reg & 0xf) << " of " << PADHEX(2) << +cycle.value8_low());
// LOG("CIA " << (((address >> 12) & 3)^3) << " " << (cycle.operation & Microcycle::Read ? "read " : "write ") << std::dec << (reg & 0xf) << " of " << PADHEX(4) << +cycle.value16());
} else if(address >= 0xdf'f000 && address <= 0xdf'f1be) {
chipset_.perform(cycle);
} else {