From 2b52c43605b2403b6097869379b717c4366601dc Mon Sep 17 00:00:00 2001
From: jborza <jborza@gmail.com>
Date: Mon, 29 Apr 2019 06:37:56 +0200
Subject: [PATCH] attempt to run nestest

---
 cpu.c              |  6 ++++++
 cpu.h              |  3 ++-
 debugger_windows.c |  2 +-
 disassembler.c     |  6 ++----
 emu6502.c          | 45 +++++++++++++++++++++++++++++----------------
 emu6502.vcxproj    |  1 +
 test6502.c         |  3 +++
 7 files changed, 44 insertions(+), 22 deletions(-)

diff --git a/cpu.c b/cpu.c
index 2a8eef5..e6f8f22 100644
--- a/cpu.c
+++ b/cpu.c
@@ -30,6 +30,12 @@ void set_NZ_flags(State6502 * state, byte value) {
 	state->flags.n = is_negative(value);
 }
 
+byte flags_as_byte(State6502* state) {
+	byte flags_value;
+	memcpy(&flags_value, &state->flags, sizeof(Flags));
+	return flags_value;
+}
+
 void clear_flags(State6502 * state) {
 	state->flags.b =
 		state->flags.c =
diff --git a/cpu.h b/cpu.h
index dea0364..81bb98f 100644
--- a/cpu.h
+++ b/cpu.h
@@ -7,4 +7,5 @@ void* unimplemented_instruction(State6502* state);
 int emulate_6502_op(State6502* state);
 
 void clear_flags(State6502* state);
-void clear_state(State6502* state);
\ No newline at end of file
+void clear_state(State6502* state);
+byte flags_as_byte(State6502* state);
\ No newline at end of file
diff --git a/debugger_windows.c b/debugger_windows.c
index a83604c..f737cbd 100644
--- a/debugger_windows.c
+++ b/debugger_windows.c
@@ -134,7 +134,7 @@ void print_frame() {
 	}
 }
 
-int main(int argc, char* argv[]) {
+int main2(int argc, char* argv[]) {
 	State6502 state;
 	clear_state(&state);
 	state.memory = malloc(MEMORY_SIZE);
diff --git a/disassembler.c b/disassembler.c
index a58fc09..8b54f0b 100644
--- a/disassembler.c
+++ b/disassembler.c
@@ -4,7 +4,7 @@
 #include <stdio.h>
 
 void disassemble_6502(byte* buffer, word pc) {
-	printf("%04X ", pc);
+	printf("%04X  ", pc);
 	byte* code = &buffer[pc];
 	int bytes = 1;
 	char op[128] = "";
@@ -182,7 +182,5 @@ void disassemble_6502(byte* buffer, word pc) {
 	else {
 		printf("   ");
 	}
-	printf(op);
-
-	printf("\n");
+	printf(" %s", op);
 }
\ No newline at end of file
diff --git a/emu6502.c b/emu6502.c
index 2996d62..9ce6848 100644
--- a/emu6502.c
+++ b/emu6502.c
@@ -9,33 +9,46 @@
 #include "disassembler.h"
 #include "opcodes.h"
 #include "test6502.h"
+#include <errno.h>
+#include <direct.h>
 
-byte* read_game() {
-	FILE* file = fopen("..\\bins\\tetris.bin", "r");
-	//byte* buffer = malloc(0x800);
-	byte buffer[32];
-	int read = fread(&buffer, sizeof(byte), 32, file);
+#define NESTEST_SIZE 0x4000
+#define NESTEST_DST 0xC000
+#define MEMORY_SIZE 0xFFFF
+
+byte* read_nestest() {
+	FILE* file = fopen("nestest\\nestest.bin", "rb");
+	if (!file) {
+		int err = errno;
+		exit(1);
+	}
+	byte buffer[NESTEST_SIZE];
+	int read = fread(&buffer, sizeof(byte), NESTEST_SIZE, file);
 	fclose(file);
 	return buffer;
 }
 
-
-
-void emulate_game() {
+void run_nestest() {
 	State6502 state;
-	//FILE* file = fopen("..\\bins\\tetris.bin", "r");
 	clear_state(&state);
-	state.memory = read_game();
-	for (int i = 0; i < 100; i++) {
-		disassemble_6502(state.memory, i);
-	}
+	state.memory = malloc(MEMORY_SIZE);
+	memset(state.memory, 0, MEMORY_SIZE);
+	byte* bin = read_nestest();
+	//const word TARGET = 0xC000;
+	memcpy(state.memory + NESTEST_DST, bin, NESTEST_SIZE);
+	memcpy(state.memory + 0x8000, bin, NESTEST_SIZE);
+	state.pc = NESTEST_DST;
+	do{
+		disassemble_6502(state.memory, state.pc);
+		emulate_6502_op(&state);
+		printf("    A:%02X X:%02X Y:%02X P:%02X SP:%02X\n", state.a, state.x, state.y, flags_as_byte(&state), state.sp);
+	} while (state.flags.b != 1);
 }
 
 int main()
 {
-	//emulate_game();
-	run_tests();
-	printf("All tests succeeded.\n");
+	run_nestest();
+	//run_tests();
 	return 0;
 }
 
diff --git a/emu6502.vcxproj b/emu6502.vcxproj
index 488157f..22a99ad 100644
--- a/emu6502.vcxproj
+++ b/emu6502.vcxproj
@@ -152,6 +152,7 @@
   </ItemDefinitionGroup>
   <ItemGroup>
     <ClCompile Include="cpu.c" />
+    <ClCompile Include="debugger_windows.c" />
     <ClCompile Include="disassembler.c" />
     <ClCompile Include="emu6502.c" />
     <ClCompile Include="memory.c" />
diff --git a/test6502.c b/test6502.c
index f913081..881ce17 100644
--- a/test6502.c
+++ b/test6502.c
@@ -40,6 +40,7 @@ void print_all(State6502 * state) {
 void test_step(State6502 * state) {
 	print_all(state);
 	disassemble_6502(state->memory, state->pc);
+	printf("\n");
 	emulate_6502_op(state);
 	print_all(state);
 }
@@ -48,6 +49,7 @@ void test_step_until_break(State6502 * state) {
 	do {
 		print_all(state);
 		disassemble_6502(state->memory, state->pc);
+		printf("\n");
 		emulate_6502_op(state);
 	} while (state->flags.b != 1);
 	print_all(state);
@@ -1870,6 +1872,7 @@ void test_PHA_PLA() {
 	//act
 	for (int i = 0; i < 9; i++) {
 		disassemble_6502(state.memory, state.pc);
+		printf("\n");
 		emulate_6502_op(&state);
 	}