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Diffstat (limited to 'src/vcpu.c')
-rw-r--r--src/vcpu.c120
1 files changed, 119 insertions, 1 deletions
diff --git a/src/vcpu.c b/src/vcpu.c
index ab7177c..c4187cb 100644
--- a/src/vcpu.c
+++ b/src/vcpu.c
@@ -2,6 +2,8 @@
#include "mem.h"
#include "screen.h"
#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
// Current VCPU state
VCPU_State State;
@@ -9,6 +11,7 @@ VCPU_State State;
void VCPUInit(){
State.PC=ADDR_ROM;
State.S=0;
+ srand(time(NULL));
}
void VCPUFetch(){
@@ -65,7 +68,7 @@ void VCPUExecute(){
State.PC+=2;
break;
;;
- case 0x5: // SNE: VX, VY
+ case 0x5: // SE: VX, VY
if(State.V[State.X]==State.V[State.Y])
State.PC+=2;
break;
@@ -78,10 +81,81 @@ void VCPUExecute(){
State.V[State.X]+=State.NN;
break
;;
+ case 0x8: // Register operations
+ switch(State.N){
+ case 0x1: // VX = VX OR VY
+ State.V[State.X]=State.V[State.X] | State.V[State.Y];
+ break;
+ ;;
+ case 0x2: // VX = VX AND VY
+ State.V[State.X]=State.V[State.X] & State.V[State.Y];
+ break;
+ ;;
+ case 0x3: // VX = VX XOR VY
+ State.V[State.X]=State.V[State.X] ^ State.V[State.Y];
+ break;
+ ;;
+ case 0x4: // VX = VX + VY
+ if(State.V[State.X] + State.V[State.Y] > 255)
+ State.V[REG_FLAG]=1;
+ else
+ State.V[REG_FLAG]=0;
+ State.V[State.X]=(State.V[State.X] + State.V[State.Y]) & 0xFF;
+ break;
+ ;;
+ case 0x5: // VX = VX - VY
+ if(State.V[State.X] > State.V[State.Y])
+ State.V[REG_FLAG]=1;
+ else
+ State.V[REG_FLAG]=0;
+ State.V[State.X]=State.V[State.X] - State.V[State.Y];
+ break;
+ ;;
+ case 0x6: // VX = VX SHR 1
+ if(State.V[State.X] & 0x1 == 1)
+ State.V[REG_FLAG]=1;
+ else
+ State.V[REG_FLAG]=0;
+ State.V[State.X]=State.V[State.X] >> 1;
+ break;
+ ;;
+ case 0x7: // VX = VY - VX
+ if(State.V[State.X] < State.V[State.Y])
+ State.V[REG_FLAG]=1;
+ else
+ State.V[REG_FLAG]=0;
+ State.V[State.X]=State.V[State.Y] - State.V[State.X];
+ break;
+ ;;
+ case 0xE: // VX = VX SHL 1
+ if(State.V[State.X] >> 15 == 1)
+ State.V[REG_FLAG]=1;
+ else
+ State.V[REG_FLAG]=0;
+ State.V[State.X]=State.V[State.X] << 1;
+ break;
+ ;;
+ }
+ break
+ ;;
+ case 0x9: // SNE: VX, VY
+ if(State.V[State.X]!=State.V[State.Y])
+ State.PC+=2;
+ break;
+ ;;
case 0xA:
State.I=State.NNN;
break
;;
+ case 0xB:
+ State.PC=State.V[0]+State.NNN;
+ break
+ ;;
+ case 0xC:
+ unsigned short n = rand() % 255 + 1;
+ State.V[State.X]=n & State.NN;
+ break
+ ;;
case 0xD: // Draw a sprite
int X=State.V[State.X]%63;
int Y=State.V[State.Y]%31;
@@ -105,6 +179,50 @@ void VCPUExecute(){
}
break;
;;
+ case 0xE:
+ // TODO
+ break;;
+ case 0xF:
+ switch(State.NN){
+ case 0x07: // Get timer
+ State.V[State.X]=State.DT;
+ break;
+ ;;
+ case 0x0A:
+ // TODO
+ break;
+ ;;
+ case 0x15: // Set timer
+ State.DT=State.V[State.X];
+ break;
+ ;;
+ case 0x18: // Set sound timer
+ State.ST=State.V[State.X];
+ break;
+ ;;
+ case 0x1E: // I = I + VX
+ State.I=State.I+State.V[State.X];
+ break;
+ ;;
+ case 0x29:
+ // TODO
+ break;
+ ;;
+ case 0x33:
+ // TODO
+ break;
+ ;;
+ case 0x55:
+ MemCopy(State.V,0xF,State.I);
+ break;
+ ;;
+ case 0x65:
+ MemRead(State.V,0xF,State.I);
+ break;
+ ;;
+ }
+ break;
+ ;;
}
}