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update formatting from Jim's aed512 version of cpu6502

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This commit is contained in:
Brad Grantham 2019-02-16 08:49:10 -08:00
parent 0bb0b6ffd4
commit fe8e4a5058
1 changed files with 12 additions and 12 deletions
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24
cpu6502.h
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@ -1,11 +1,11 @@
/*
Public methods:
CPU6502(CLK& clk, BUS& bus); - construct using clk and bus
cycle() - issue one instruction and add necessary cycles to clk
cycle() - issue one instruction and add necessary cycles to clk
reset() - reset CPU state
irq() - put CPU in IRQ
nmi() - put CPU in NMI
CLK template parameter must provide methods:
void add_cpu_cycles(int N); - add N CPU cycles to the clock
@ -100,15 +100,15 @@ struct CPU6502
}
static bool sbc_overflow_d(unsigned char a, unsigned char b, int borrow)
{
signed char a_ = a;
{
signed char a_ = a;
signed char b_ = b;
signed short c = a_ - (b_ + borrow);
return (c < 0) || (c > 99);
}
static bool adc_overflow_d(unsigned char a, unsigned char b, int carry)
{
{
signed char a_ = a;
signed char b_ = b;
signed short c = a_ + b_ + carry;
@ -152,8 +152,8 @@ struct CPU6502
void irq()
{
stack_push((pc + 0) >> 8);
stack_push((pc + 0) & 0xFF);
stack_push((pc - 1) >> 8);
stack_push((pc - 1) & 0xFF);
stack_push(p);
pc = bus.read(0xFFFE) + bus.read(0xFFFF) * 256;
exception = NONE;
@ -161,8 +161,8 @@ struct CPU6502
void nmi()
{
stack_push((pc + 0) >> 8);
stack_push((pc + 0) & 0xFF);
stack_push((pc - 1) >> 8);
stack_push((pc - 1) & 0xFF);
stack_push(p);
pc = bus.read(0xFFFA) + bus.read(0xFFFB) * 256;
exception = NONE;
@ -1222,7 +1222,7 @@ struct CPU6502
set_flags(N | Z, a = a ^ m);
break;
}
case 0x41: { // EOR (ind, X)
unsigned char zpg = (read_pc_inc() + x) & 0xFF;
int addr = bus.read(zpg) + bus.read((zpg + 1) & 0xFF) * 256;
@ -1319,7 +1319,7 @@ struct CPU6502
set_flags(N | Z, m = a - m);
break;
}
case 0xE4: { // CPX
unsigned char zpg = read_pc_inc();
m = bus.read(zpg);
@ -1502,7 +1502,7 @@ struct CPU6502
};
template<class CLK, class BUS>
int CPU6502<CLK, BUS>::cycles[256] =
int CPU6502<CLK, BUS>::cycles[256] =
{
/* 0x0- */ 7, 6, -1, -1, -1, 3, 5, -1, 3, 2, 2, -1, -1, 4, 6, -1,
/* 0x1- */ 2, 5, 5, -1, -1, 4, 6, -1, 2, 4, 2, -1, -1, 4, 7, -1,