Made variable names slightly more consistent

6502-emu.c

@@ -6,7 +6,7 @@
 #include "6502.h"
 #include "6850.h"
 
-struct termios oldTermios;
+struct termios initial_termios;
 
 void step_delay()
 {
@@ -32,17 +32,17 @@ void run_cpu()
 
 void restore_stdin()
 {
-	tcsetattr(0, TCSANOW, &oldTermios);
+	tcsetattr(0, TCSANOW, &initial_termios);
 }
 
 void raw_stdin()
 {
-	struct termios newTermios;
+	struct termios new_termios;
 	
-	tcgetattr(0, &oldTermios);
-	newTermios = oldTermios;
-	cfmakeraw(&newTermios);
-	tcsetattr(0, TCSANOW, &newTermios);
+	tcgetattr(0, &initial_termios);
+	new_termios = initial_termios;
+	cfmakeraw(&new_termios);
+	tcsetattr(0, TCSANOW, &new_termios);
 	atexit(restore_stdin);
 }
 

6502.c

@@ -14,12 +14,12 @@ int jumping; // used to check that we don't need to increment the PC after a jum
 
 /* Flag Checks */
 
-static inline void Nflag(int8_t val)
+static inline void N_flag(int8_t val)
 {
 	SR.bits.sign = val < 0;
 }
 
-static inline void Zflag(uint8_t val)
+static inline void Z_flag(uint8_t val)
 {
 	SR.bits.zero = val == 0;
 }
@@ -40,12 +40,12 @@ static inline uint8_t stack_pull()
 
 static inline uint8_t * read_ptr()
 {
-	return readAddr = get_ptr[inst.mode]();
+	return read_addr = get_ptr[inst.mode]();
 }
 
 static inline uint8_t * write_ptr()
 {
-	return writeAddr = get_ptr[inst.mode]();
+	return write_addr = get_ptr[inst.mode]();
 }
 
 /* Instruction Implementations */
@@ -57,15 +57,15 @@ static void inst_ADC()
 	SR.bits.carry = tmp > 0xFF;
 	SR.bits.overflow =  ((A^tmp)&(operand^tmp)&0x80) != 0;
 	A = tmp & 0xFF;
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 static void inst_AND()
 {
 	A &= * read_ptr();
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 static void inst_ASL()
@@ -73,8 +73,8 @@ static void inst_ASL()
 	uint8_t tmp = * read_ptr();
 	SR.bits.carry = (tmp & 0x80) != 0;
 	tmp <<= 1;
-	Nflag(tmp);
-	Zflag(tmp);
+	N_flag(tmp);
+	Z_flag(tmp);
 	* write_ptr() = tmp;
 }
 
@@ -102,8 +102,8 @@ static void inst_BEQ()
 static void inst_BIT()
 {
 	uint8_t tmp = * read_ptr();
-	Nflag(tmp);
-	Zflag(tmp & A);
+	N_flag(tmp);
+	Z_flag(tmp & A);
 	SR.bits.overflow = (tmp & 0x40) != 0;
 }
 
@@ -180,8 +180,8 @@ static void inst_CMP()
 {
 	uint8_t operand = * read_ptr();
 	uint8_t tmpDiff = A - operand;
-	Nflag(tmpDiff);
-	Zflag(tmpDiff);
+	N_flag(tmpDiff);
+	Z_flag(tmpDiff);
 	SR.bits.carry = A >= operand;
 }
 
@@ -189,8 +189,8 @@ static void inst_CPX()
 {
 	uint8_t operand = * read_ptr();
 	uint8_t tmpDiff = X - operand;
-	Nflag(tmpDiff);
-	Zflag(tmpDiff);
+	N_flag(tmpDiff);
+	Z_flag(tmpDiff);
 	SR.bits.carry = X >= operand;
 }
 
@@ -198,8 +198,8 @@ static void inst_CPY()
 {
 	uint8_t operand = * read_ptr();
 	uint8_t tmpDiff = Y - operand;
-	Nflag(tmpDiff);
-	Zflag(tmpDiff);
+	N_flag(tmpDiff);
+	Z_flag(tmpDiff);
 	SR.bits.carry = Y >= operand;
 }
 
@@ -207,53 +207,53 @@ static void inst_DEC()
 {
 	uint8_t tmp = * read_ptr();
 	tmp--;
-	Nflag(tmp);
-	Zflag(tmp);
+	N_flag(tmp);
+	Z_flag(tmp);
 	* write_ptr() = tmp;
 }
 
 static void inst_DEX()
 {
 	X--;
-	Nflag(X);
-	Zflag(X);
+	N_flag(X);
+	Z_flag(X);
 }
 
 static void inst_DEY()
 {
 	Y--;
-	Nflag(Y);
-	Zflag(Y);
+	N_flag(Y);
+	Z_flag(Y);
 }
 
 static void inst_EOR()
 {
 	A ^= * read_ptr();
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 static void inst_INC()
 {
 	uint8_t tmp = * read_ptr();
 	tmp++;
-	Nflag(tmp);
-	Zflag(tmp);
+	N_flag(tmp);
+	Z_flag(tmp);
 	* write_ptr() = tmp;
 }
 
 static void inst_INX()
 {
 	X++;
-	Nflag(X);
-	Zflag(X);
+	N_flag(X);
+	Z_flag(X);
 }
 
 static void inst_INY()
 {
 	Y++;
-	Nflag(Y);
-	Zflag(Y);
+	N_flag(Y);
+	Z_flag(Y);
 }
 
 static void inst_JMP()
@@ -275,22 +275,22 @@ static void inst_JSR()
 static void inst_LDA()
 {
 	A = * read_ptr();
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 static void inst_LDX()
 {
 	X = * read_ptr();
-	Nflag(X);
-	Zflag(X);
+	N_flag(X);
+	Z_flag(X);
 }
 
 static void inst_LDY()
 {
 	Y = * read_ptr();
-	Nflag(Y);
-	Zflag(Y);
+	N_flag(Y);
+	Z_flag(Y);
 }
 
 static void inst_LSR()
@@ -298,8 +298,8 @@ static void inst_LSR()
 	uint8_t tmp = * read_ptr();
 	SR.bits.carry = tmp & 1;
 	tmp >>= 1;
-	Nflag(tmp);
-	Zflag(tmp);
+	N_flag(tmp);
+	Z_flag(tmp);
 	* write_ptr() = tmp;
 }
 
@@ -311,8 +311,8 @@ static void inst_NOP()
 static void inst_ORA()
 {
 	A |= * read_ptr();
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 static void inst_PHA()
@@ -329,8 +329,8 @@ static void inst_PHP()
 static void inst_PLA()
 {
 	A = stack_pull();
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 static void inst_PLP()
@@ -345,8 +345,8 @@ static void inst_ROL()
 	tmp |= SR.bits.carry & 1;
 	SR.bits.carry = tmp > 0xFF;
 	tmp &= 0xFF;
-	Nflag(tmp);
-	Zflag(tmp);
+	N_flag(tmp);
+	Z_flag(tmp);
 	* write_ptr() = tmp;
 }
 
@@ -356,8 +356,8 @@ static void inst_ROR()
 	tmp |= SR.bits.carry << 8;
 	SR.bits.carry = tmp & 1;
 	tmp >>= 1;
-	Nflag(tmp);
-	Zflag(tmp);
+	N_flag(tmp);
+	Z_flag(tmp);
 	* write_ptr() = tmp;
 }
 
@@ -386,8 +386,8 @@ static void inst_SBC()
 	SR.bits.carry = tmp > 0xFF;
 	SR.bits.overflow =  ((A^tmp)&(operand^tmp)&0x80) != 0;
 	A = tmp & 0xFF;
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 static void inst_SEC()
@@ -424,29 +424,29 @@ static void inst_STY()
 static void inst_TAX()
 {
 	X = A;
-	Nflag(X);
-	Zflag(X);
+	N_flag(X);
+	Z_flag(X);
 }
 
 static void inst_TAY()
 {
 	Y = A;
-	Nflag(Y);
-	Zflag(Y);
+	N_flag(Y);
+	Z_flag(Y);
 }
 
 static void inst_TSX()
 {
 	X = SP;
-	Nflag(X);
-	Zflag(X);
+	N_flag(X);
+	Z_flag(X);
 }
 
 static void inst_TXA()
 {
 	A = X;
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 static void inst_TXS()
@@ -457,8 +457,8 @@ static void inst_TXS()
 static void inst_TYA()
 {
 	A = Y;
-	Nflag(A);
-	Zflag(A);
+	N_flag(A);
+	Z_flag(A);
 }
 
 /* Addressing Implementations */

6502.h

@@ -16,8 +16,8 @@ uint8_t Y;
 uint16_t PC;
 uint8_t SP; // points to first empty stack location
 
-void * readAddr;
-void * writeAddr;
+void * read_addr;
+void * write_addr;
 
 struct StatusBits{
 	int carry:1; // bit 0

6850.c

@@ -15,7 +15,7 @@ void init_uart() {
 	uart_SR.bits.TDRE = 1; // we are always ready to output data
 	
 	uart_SR.bits.RDRF = 0;
-	incomingChar = 0;
+	incoming_char = 0;
 	
 }
 
@@ -27,22 +27,22 @@ int stdin_ready() {
 }
 
 void step_uart() {
-	if (writeAddr == &memory[DATA_ADDR]) {
+	if (write_addr == &memory[DATA_ADDR]) {
 		putchar(memory[DATA_ADDR]);
 		fflush(stdout);
-		writeAddr = NULL;
-	} else if (readAddr == &memory[DATA_ADDR]) {
+		write_addr = NULL;
+	} else if (read_addr == &memory[DATA_ADDR]) {
 		uart_SR.bits.RDRF = 0;
-		readAddr = NULL;
+		read_addr = NULL;
 	}
 	
 	/* update input register if empty */
 	if ((n++ % 10000) == 0) { // polling stdin every cycle is performance intensive. This is a bit of a dirty hack.
 		if (!uart_SR.bits.RDRF && stdin_ready()) { // the real hardware has no buffer. Remote the RDRF check for more accurate emulation.
-			if (read(0, &incomingChar, 1) != 1) {
+			if (read(0, &incoming_char, 1) != 1) {
 				printf("Warning: read() returned 0\n");
 			}
-			if (incomingChar == 0x18) { // CTRL+X
+			if (incoming_char == 0x18) { // CTRL+X
 				printf("\r\n");
 				exit(0);
 			}
@@ -50,6 +50,6 @@ void step_uart() {
 		}
 	}
 	
-	memory[DATA_ADDR] = incomingChar;
+	memory[DATA_ADDR] = incoming_char;
 	memory[CTRL_ADDR] = uart_SR.byte;
 }

6850.h

@@ -19,7 +19,7 @@ union UartStatusReg {
 
 union UartStatusReg uart_SR;
 
-uint8_t incomingChar;
+uint8_t incoming_char;
 
 void init_uart();
 

main.c

@@ -1,71 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <termios.h>
-#include <time.h>
-
-#include "6502.h"
-#include "6850.h"
-
-struct termios oldTermios;
-
-void step_delay()
-{
-	struct timespec req, rem;
-	
-	req.tv_sec = 0;
-	req.tv_nsec = STEP_DURATION;
-	
-	nanosleep(&req, &rem);
-}
-
-void run_cpu()
-{
-	for (;;) {		
-		// CPU timing is currently very far from being cycle-accurate
-		for (int i = 0; i < (CPU_FREQ / (ONE_SECOND / STEP_DURATION)); i++) {
-			step_cpu();
-			step_uart();
-		}
-		step_delay(); // remove this for more speed
-	}
-}
-
-void restore_stdin()
-{
-	tcsetattr(0, TCSANOW, &oldTermios);
-}
-
-void raw_stdin()
-{
-	struct termios newTermios;
-	
-	tcgetattr(0, &oldTermios);
-	newTermios = oldTermios;
-	cfmakeraw(&newTermios);
-	tcsetattr(0, TCSANOW, &newTermios);
-	atexit(restore_stdin);
-}
-
-int main(int argc, char *argv[])
-{
-	if (argc != 2) {
-		printf("Usage: %s file.rom\n", argv[0]);
-		printf("The first 16k of \"file.rom\" is loaded into the last 16k of memory.\n");
-		return EXIT_FAILURE;
-	}
-	
-	if (load_rom(argv[1]) != 0) {
-		printf("Error loading \"%s\".\n", argv[1]);
-		return EXIT_FAILURE;
-	}
-	
-	raw_stdin(); // allow individual keystrokes to be detected
-	
-	init_tables();
-	init_uart();
-	
-	reset_cpu();
-	run_cpu();
-	
-	return EXIT_SUCCESS;
-}