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-rw-r--r--applesystem.h113
1 files changed, 0 insertions, 113 deletions
diff --git a/applesystem.h b/applesystem.h
deleted file mode 100644
index 6b2f818..0000000
--- a/applesystem.h
+++ /dev/null
@@ -1,113 +0,0 @@
-// applesystem.h
-// Core elements of the 6502 CPU, and flag manipulation.
-
-typedef unsigned char byte;
-typedef unsigned short address;
-byte acc, X, Y, P, S = 0x00;
-address PC = 0x0000;
-byte Memory[4096]; // TO DO. Add expansion capability to memory.
-
-// FLAGS
-const byte flag_N = 0x80; // Negative
-const byte flag_V = 0x40; // Overflow
-const byte flag_B = 0x10; // BRK command
-const byte flag_D = 0x08; // Decimal mode
-const byte flag_I = 0x04; // IRQ disable
-const byte flag_Z = 0x02; // Zero
-const byte flag_C = 0x01; // Carry
-
-byte getFlag(byte flag) {
- return ((P & flag) == flag) ? 1 : 0;
-}
-
-void setFlag(byte flag, int x) { //OVERLOAD TO ACCEPT INT AS WELL
- if (x == 1){
- if ((P & flag) == 0x0) P += flag;
- }else if (x == 0){
- if ((P & flag) == flag) P -= flag;
- }
- else{
- fprintf(stderr, "setFlag() passed arg neither 0 or 1");
- }
-}
-
-void flagSet(byte flag){
- P |= flag;
-}
-
-void flagClear(byte flag){
- P &= ~flag;
-}
-
-
-// BCD
-// need to actually look into BCD on the 6502
-byte toBCD(byte x){
- if (x < 100){
- byte a = ((x / 10) << 4);
- byte b = (x % 10);
- return (a + b);
- }
- else{
- fprintf(stderr, "Number greater than 99 passed to toBCD()");
- }
-}
-
-byte fromBCD(byte x){
- byte a = ((x >> 4) * 10);
- byte b = (x & 0xF);
- return (a + b);
-}
-
-
-// Functions which perform reusable routines for finding if a specific flag should be set.
-
-void setFlagN(byte x){
- if (x & flag_N == flag_N)
- setFlag(flag_N, 1);
- else
- setFlag(flag_N, 0);
-}
-
-//Perform prior to any changes
-void setFlagV(byte x, byte y){
- if ((x & flag_N) == (y & flag_N)){
- if (((x + y) & (flag_N ^ 0xFF)) > 0x7F) setFlag(flag_V, 1);
- else setFlag(flag_V, 0);
- }else{
- if (((x - y) & (flag_N ^ 0xFF)) > 0x7F) setFlag(flag_V, 1);
- else setFlag(flag_V, 0);
- }
-}
-
-/*void setFlagB(){ //WORK ON
- setFlag(flag_B, 1);
-}*/ //Dont really need since its dependent on the BRK insturction
-
-/*void setFlagD(){
- setFlag(flag_D, 1);
-}*/
-
-/*void setFlagI(){ //WORK ON
- setFlag(flag_Z, 1);
-}*/
-
-void setFlagZ(int x){
- if (x == 0)
- setFlag(flag_Z, 1);
- else
- setFlag(flag_Z, 0);
-}
-
-//Only 6 instructions, 2 not including stack instructions, use the carry flag.
-// Need to look further into implementation details for this.
-/*void setFlagC(){
- setFlag(flag_Z, 1);
-}*/
-
-
-
-
-
-
-