From 78423708c532bacf95ebc1a4155fe1d43d3d91db Mon Sep 17 00:00:00 2001
From: David Banks <dave@hoglet.com>
Date: Sun, 4 Jul 2021 19:31:13 +0100
Subject: [PATCH] Z80: Ignore machine state in disasseble command

Change-Id: I28b67a53ec8936bb9172aa10ca6548fe0d9e6460
---
 firmware/AtomBusMon.c |  4 ++--
 firmware/dis.h        |  6 +++++-
 firmware/dis6502.c    |  2 +-
 firmware/dis65c02.c   |  2 +-
 firmware/dis6809.c    |  2 +-
 firmware/disz80.c     | 12 ++++++++----
 6 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/firmware/AtomBusMon.c b/firmware/AtomBusMon.c
index b5c93b8..eb2fcfb 100644
--- a/firmware/AtomBusMon.c
+++ b/firmware/AtomBusMon.c
@@ -922,7 +922,7 @@ void writeIOByteInc() {
 
 addr_t disMem(addr_t addr) {
   loadAddr(addr);
-  return disassemble(addr);
+  return disassemble(addr, MODE_NORMAL);
 }
 
 void genericDump(char *params, data_t (*readFunc)()) {
@@ -1526,7 +1526,7 @@ void doCmdDis(char *params) {
   memAddr = startAddr;
   loadAddr(memAddr);
   do {
-    memAddr = disassemble(memAddr);
+     memAddr = disassemble(memAddr, MODE_DIS_CMD);
     i++;
   } while ((!endAddr && i < 10) || (endAddr && memAddr > startAddr && memAddr <= endAddr));
 }
diff --git a/firmware/dis.h b/firmware/dis.h
index 33e42f7..8c60c04 100644
--- a/firmware/dis.h
+++ b/firmware/dis.h
@@ -6,6 +6,10 @@
 #define PDC_DDR          DDRA
 #define PDC_DIN          PINA
 
-addr_t disassemble(addr_t addr);
+#define MODE_NORMAL      0
+#define MODE_DIS_CMD     1
+
+addr_t disassemble(addr_t addr, uint8_t m);
+
 
 #endif
diff --git a/firmware/dis6502.c b/firmware/dis6502.c
index 9b0a655..328436e 100644
--- a/firmware/dis6502.c
+++ b/firmware/dis6502.c
@@ -167,7 +167,7 @@ static const unsigned char dopaddr[256] PROGMEM =
 /*F0*/ BRA, INDY,  IMP, IMP,  ZP,   ZPX,   ZPX,  IMP,   IMP,  ABSY,  IMP,   IMP,  ABS,    ABSX,  ABSX, IMP
 };
 
-addr_t disassemble(addr_t addr)
+addr_t disassemble(addr_t addr, uint8_t m)
 {
 
   char buffer[40];
diff --git a/firmware/dis65c02.c b/firmware/dis65c02.c
index 2b06f47..d4ad91e 100644
--- a/firmware/dis65c02.c
+++ b/firmware/dis65c02.c
@@ -187,7 +187,7 @@ static const unsigned char dopaddr[256] PROGMEM =
 /*F0*/ BRA, INDY,  IND, IMP,  ZP,   ZPX,   ZPX,  IMP,   IMP,  ABSY,  IMP,   IMP,  ABS,    ABSX,  ABSX, IMP
 };
 
-addr_t disassemble(addr_t addr)
+addr_t disassemble(addr_t addr, uint8_t m)
 {
 
   char buffer[40];
diff --git a/firmware/dis6809.c b/firmware/dis6809.c
index 31725ce..454b3ce 100644
--- a/firmware/dis6809.c
+++ b/firmware/dis6809.c
@@ -647,7 +647,7 @@ static char *strcc(char *ptr, uint8_t val) {
 
 /* disassemble one instruction at address addr and return the address of the next instruction */
 
-addr_t disassemble(addr_t addr) {
+addr_t disassemble(addr_t addr, uint8_t m) {
   uint8_t d = get_memb(addr);
   uint8_t s;
   int8_t i;
diff --git a/firmware/disz80.c b/firmware/disz80.c
index 49ef72d..a65dfe5 100644
--- a/firmware/disz80.c
+++ b/firmware/disz80.c
@@ -887,12 +887,15 @@ char * disassem (char *ptr, unsigned int *ip) {
   return ptr;
 }
 
-addr_t disassemble(addr_t addr) {
+addr_t disassemble(addr_t addr, uint8_t m) {
   static char buffer[64];
 
   char *ptr;
   addr_t addr2 = addr;
 
+  // Ignore the current CPU state in the disassemble connamd
+  uint8_t pdc = (m == MODE_DIS_CMD) ? 0 : PDC_DIN;
+
   // 0123456789012345678901234567890123456789
   // AAAA : HH HH HH HH : LD   RR,($XXXX)
 
@@ -905,11 +908,12 @@ addr_t disassemble(addr_t addr) {
 
   // Opcode
   ptr = buffer + 21;
-  if (PDC_DIN & 0x80) {
+
+  if (pdc & 0x80) {
     strcpy_P(ptr, msg_HALT);
-  } else if (PDC_DIN & 0x40) {
+  } else if (pdc & 0x40) {
     strcpy(ptr, msg_NMI);
-  } else if (PDC_DIN & 0x20) {
+  } else if (pdc & 0x20) {
     strcpy(ptr, msg_INT);
   } else {
     ptr = disassem(ptr, &addr2);