From 6b1c53dad5462166a64ff851c3bdb239fbdcff1d Mon Sep 17 00:00:00 2001
From: Ain <41307858+nero@users.noreply.github.com>
Date: Fri, 15 Nov 2019 14:42:07 +0000
Subject: [PATCH] 8080 Emulator can now do most opcodes

Still very buggy
---
 .gitignore         |  2 +-
 src/utils/em8080.c | 99 +++++++++++++++++++++++++++++++++++++++++++---
 2 files changed, 95 insertions(+), 6 deletions(-)

diff --git a/.gitignore b/.gitignore
index 9f37b96..08fc7ba 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,4 +7,4 @@
 *.exe
 *.log
 *.sys
-utils/emul
+utils
diff --git a/src/utils/em8080.c b/src/utils/em8080.c
index 3024623..b01005f 100644
--- a/src/utils/em8080.c
+++ b/src/utils/em8080.c
@@ -96,6 +96,14 @@ uint16_t pop() {
   return v;
 }
 
+void in(uint8_t port) {
+
+}
+
+void out(uint8_t port) {
+
+}
+
 int has_even_parity(uint8_t x){
   unsigned int count = 0, i, b = 1;
 
@@ -115,19 +123,35 @@ void cpm_syscall(int number) {
   case 2:
     printf("%c", E);
     break;
+  case 0x0C:
+    H=0x02;
+    L=0x00;
+    break;;
   default:
-    fprintf(stderr, "Fatal: Unhandled CP/M syscall %Xh\n", number);
+    fprintf(stderr, "Fatal: Unhandled CP/M syscall C=%02Xh\n", number);
     exit(1);
   }
 }
-void handle_intr(int number) {
-  switch(number) {
+
+void call(uint16_t v) {
+  switch(v) {
+  case 0:
+    exit(0);
+    break;;
+  case 5:
+    cpm_syscall(C);
+    break;;
   default:
-    fprintf(stderr, "Fatal: Unhandled interrupt %Xh\n", number);
-    exit(1);
+    push(IP);
+    IP=v;
+    break;
   }
 }
 
+void interrupt(int number) {
+  call(number << 3);
+}
+
 #define add16c(a, b) \
   tmp = a + b; \
   flags.c = (tmp >> 16) & 1
@@ -361,6 +385,71 @@ void step() {
   case 0xBE: aritht(A, -, M); break;;
   case 0xBF: aritht(A, -, A); break;;
 
+  case 0xC0: if (!flags.z) IP=pop(); break;;
+  case 0xC1: BC=pop(); break;;
+  case 0xC2: if (!flags.z) IP=imm16(); break;;
+  case 0xC3: IP=imm16(); break;;
+  case 0xC4: if (!flags.z) call(imm16()); break;;
+  case 0xC5: push(BC); break;;
+  case 0xC6: arith(A, +, imm8()); break;;
+  case 0xC7: interrupt(0); break;;
+
+  case 0xC8: if (flags.z) IP=pop(); break;;
+  case 0xC9: IP=pop(); break;;
+  case 0xCA: if (flags.z) IP=imm16(); break;;
+  case 0xCC: if (flags.z) call(imm16()); break;;
+  case 0xCD: call(imm16()); break;;
+  case 0xCE: arith(A, +flags.c+, imm8()); break;;
+  case 0xCF: interrupt(1); break;;
+
+  case 0xD0: if (!flags.c) IP=pop(); break;;
+  case 0xD1: DE=pop(); break;;
+  case 0xD2: if (!flags.c) IP=imm16(); break;;
+  case 0xD3: out(imm8()); break;;
+  case 0xD4: if (!flags.c) call(imm16()); break;;
+  case 0xD5: push(DE); break;;
+  case 0xD6: arith(A, -, imm8()); break;;
+  case 0xD7: interrupt(2); break;;
+
+  case 0xD8: if (flags.c) IP=pop(); break;;
+  case 0xDA: if (flags.c) IP=imm16(); break;;
+  case 0xDB: in(imm8()); break;;
+  case 0xDC: if (flags.c) call(imm16()); break;;
+  case 0xDE: arith(A, -flags.c-, imm8()); break;;
+  case 0xDF: interrupt(3); break;;
+
+  case 0xE0: if (!flags.p) IP=pop(); break;;
+  case 0xE1: HL=pop(); break;;
+  case 0xE2: if (!flags.p) IP=imm16(); break;;
+  case 0xE3: tmp=HL; HL=pop(); push(tmp); break;;
+  case 0xE4: if (!flags.p) call(imm16()); break;;
+  case 0xE5: push(HL); break;;
+  case 0xE6: arith(A, &, imm8()); break;;
+  case 0xE7: interrupt(4); break;;
+
+  case 0xE8: if (flags.p) IP=pop(); break;;
+  case 0xE9: IP=HL; break;;
+  case 0xEA: if (flags.p) IP=imm16(); break;;
+  case 0xEB: tmp=HL; HL=DE; DE=tmp;; break;;
+  case 0xEC: if (flags.p) call(imm16()); break;;
+  case 0xEE: arith(A, ^, imm8()); break;;
+  case 0xEF: interrupt(5); break;;
+
+  case 0xF0: if (!flags.s) IP=pop(); break;;
+  case 0xF1: regset.regp.psw=pop(); break;;
+  case 0xF2: if (!flags.s) IP=imm16(); break;;
+  case 0xF4: if (!flags.s) call(imm16()); break;;
+  case 0xF5: push(regset.regp.psw); break;;
+  case 0xF6: arith(A, |, imm8()); break;;
+  case 0xF7: interrupt(6); break;;
+
+  case 0xF8: if (flags.s) IP=pop(); break;;
+  case 0xF9: SP=HL; break;;
+  case 0xFA: if (flags.s) IP=imm16(); break;;
+  case 0xFC: if (flags.s) call(imm16()); break;;
+  case 0xFE: aritht(A, -, imm8()); break;;
+  case 0xFF: interrupt(7); break;;
+
   default:
     IP--;
     dump();