From 85bc469a9c23db5f622a51ed6220e3c9dea6e868 Mon Sep 17 00:00:00 2001
From: Luxdragon <kopse@e.email>
Date: Sun, 14 Jan 2024 11:00:05 +0100
Subject: [PATCH] Still having I/O problems

---
 emulator_shell.c | 87 ++++++++++++++++++++++++------------------------
 1 file changed, 44 insertions(+), 43 deletions(-)

diff --git a/emulator_shell.c b/emulator_shell.c
index 22c2971..d2738f9 100644
--- a/emulator_shell.c
+++ b/emulator_shell.c
@@ -397,6 +397,35 @@ void printState(State8080* state) {
         state->e, state->h, state->l, state->sp); 
 }
 
+uint8_t machineIn(State8080* state, uint8_t port) {
+    uint8_t a;
+    switch(port) {
+        case 3:
+        {
+            uint16_t v = (state->shift1<<8) | (state->shift0);
+            a = ((v >> (8-state->shift_offset)) & 0xff);
+        }
+        break;
+    }
+    return a;
+}
+
+uint8_t machineOut(State8080* state, uint8_t port, uint8_t value) {
+    switch(port) {
+        case 2:
+        {
+            state->shift_offset = value & 0x7;
+        } break;
+        case 4:
+        {   
+            state->shift0 = state->shift1;
+            state->shift1 = value;
+            break;
+        }
+    }
+}
+
+
 int emulate8080(State8080* state) {
     unsigned char *opcode = &(state->memory[state->pc]);
 
@@ -696,7 +725,8 @@ int emulate8080(State8080* state) {
             state->sp += 2;
             break;
         case 0xd3:              // OUT byte
-            //printf("%c", opcode[1]);
+            uint8_t port = opcode[1];
+            machineOut(state, port, 0x00); // PROBLEM: We need to pass a value to machineOUT
             state->pc++;
             break;
         case 0xd5:              // PUSH D
@@ -705,7 +735,8 @@ int emulate8080(State8080* state) {
             state->sp -= 2;
             break;
         case 0xdb:              // IN byte
-            //printf("%c", opcode[1]);
+            uint8_t port = opcode[1];
+            state->a = machineIn(state, port);
             state->pc++;
             break;
         case 0xe1:              // POP H
@@ -781,9 +812,19 @@ int emulate8080(State8080* state) {
         default: unknownInstruction(state); break;
     }
     printState(state);
-    
 }
 
+   void GenerateInterrupt(State8080* state, int interrupt_num)    
+   {    
+        //perform "PUSH PC"    
+       Push(state, (state->pc & 0xFF00) >> 8, (state->pc & 0xff));    
+
+        //Set the PC to the low memory vector.    
+        //This is identical to an "RST interrupt_num" instruction.    
+    state->pc = 8 * interrupt_num;    
+   }    
+
+
 void read_Space_Invaders_ROM(State8080* state, const char* filename, int offset) {
     //Works exclusively with the memory system of Space Invaders
     FILE* file = fopen(filename, "rb");
@@ -802,34 +843,6 @@ void read_Space_Invaders_ROM(State8080* state, const char* filename, int offset)
     fclose(file);    
 }
 
-uint8_t machineIn(State8080* state, uint8_t port) {
-    uint8_t a;
-    switch(port) {
-        case 3:
-        {
-            uint16_t v = (state->shift1<<8) | (state->shift0);
-            a = ((v >> (8-state->shift_offset)) & 0xff);
-        }
-        break;
-    }
-    return a;
-}
-
-uint8_t machineOut(State8080* state, uint8_t port, uint8_t value) {
-    uint8_t a;
-    switch(port) {
-        case 2:
-        {
-            state->shift_offset = value & 0x7;
-        } break;
-        case 4:
-        {   
-            state->shift0 = state->shift1;
-            state->shift1 = value;
-            break;
-        }
-    }
-}
 
 int main (int argc, char *argv[])  {
     gtk_init(&argc, &argv);
@@ -861,18 +874,6 @@ int main (int argc, char *argv[])  {
     char done = 0;
 
     while (!done) {
-        uint8_t* opcode = &state->memory[state->pc];
-        printf("%d\t\t:", i);
-
-        if (*opcode == 0xdb) {
-            uint8_t port = opcode[1];
-            state->a = machineIn(state, port);
-            state->pc++;
-        } else if (*opcode == 0xd3) {
-            uint8_t port = opcode[1];
-            machineOut(state, port, 0x00);
-            state->pc++;
-        }
         emulate8080(state);
         i++;
         sleep(0.00001);