Apple-2-Tools/bradgrantham-apple2e
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add INC, DEC, and STA (zpg)

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This commit is contained in:
Brad Grantham 2018-07-28 02:50:09 -07:00
parent 471fdffcf5
commit c3adb3abe6
1 changed files with 26 additions and 5 deletions
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31
apple2e.cpp
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@ -49,7 +49,10 @@ struct system_clock
clk_t operator++(int) { clk_t v = value; value ++; return v; }
} clk;
const int machine_clock_rate = 1023000;
// was 1023000
// 3.579545 * 4 / 14
// 1.02272714285714285714
const int machine_clock_rate = 1022727;
bool read_blob(char *name, unsigned char *b, size_t sz)
{
@ -986,7 +989,7 @@ struct CPU6502
static const unsigned char I = 0x04;
static const unsigned char Z = 0x02;
static const unsigned char C = 0x01;
int pc;
int pc = 0;
enum Exception {
NONE,
RESET,
@ -2027,7 +2030,7 @@ struct CPU6502
break;
}
case 0x91: { // STA
case 0x91: { // STA (ind), Y
unsigned char zpg = read_pc_inc(bus);
int addr = bus.read(zpg) + bus.read((zpg + 1) & 0xFF) * 256 + y;
bus.write(addr, a);
@ -2352,6 +2355,23 @@ struct CPU6502
break;
}
case 0x92: { // STA (zpg), 65C02 instruction!
unsigned char zpg = read_pc_inc(bus);
int addr = bus.read(zpg) + bus.read((zpg + 1) & 0xFF) * 256;
bus.write(addr, a);
break;
}
case 0x3A: { // DEC
set_flags(N | Z, a = a - 1);
break;
}
case 0x1A: { // INC
set_flags(N | Z, a = a + 1);
break;
}
default:
printf("unhandled instruction %02X\n", inst);
fflush(stdout); exit(1);
@ -2602,6 +2622,7 @@ enum APPLE2Einterface::EventType process_events(MAINboard *board, bus_frontend&
return APPLE2Einterface::NONE;
}
extern uint16_t pc;
int main(int argc, char **argv)
{
@ -2740,7 +2761,7 @@ int main(int argc, char **argv)
clk_t prev_clock = clk;
while(clk - prev_clock < clocks_per_slice) {
if(debug & DEBUG_DECODE) {
string dis = read_bus_and_disassemble(bus, cpu.pc);
string dis = read_bus_and_disassemble(bus, use_fake6502 ? pc : cpu.pc);
printf("%s\n", dis.c_str());
}
if(use_fake6502) {
@ -2804,7 +2825,7 @@ int main(int argc, char **argv)
continue;
}
if(debug & DEBUG_DECODE) {
string dis = read_bus_and_disassemble(bus, cpu.pc);
string dis = read_bus_and_disassemble(bus, use_fake6502 ? pc : cpu.pc);
printf("%s\n", dis.c_str());
}