From e4cf98bfe1b811abec1ffd9a3195e94b5c041dfc Mon Sep 17 00:00:00 2001
From: Godzil <godzil@godzil.net>
Date: Sun, 4 Apr 2021 21:05:48 +0100
Subject: [PATCH] Add a debug function to log all access to IO regs.

---
 source/io.cpp      | 22 ++++++++++++++++++++++
 source/nec/nec.cpp | 10 ++++++++--
 2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/source/io.cpp b/source/io.cpp
index 400b816..7cc3be8 100644
--- a/source/io.cpp
+++ b/source/io.cpp
@@ -29,10 +29,13 @@
 #include "audio.h"
 #include "memory.h"
 
+#define IO_DUMP
+
 extern uint8_t *externalEeprom;
 extern uint32_t romAddressMask;
 extern uint16_t *internalEeprom;
 extern nec_Regs I;
+extern uint64_t nec_monotonicCycles;
 
 enum
 {
@@ -86,6 +89,8 @@ uint8_t ws_key_flipped;
 
 int      rtcDataRegisterReadCount=0;
 
+FILE *ioLogFp = NULL;
+
 ////////////////////////////////////////////////////////////////////////////////
 //
 ////////////////////////////////////////////////////////////////////////////////
@@ -139,6 +144,10 @@ void ws_io_init(void)
 
    ws_io_reset();
    ws_key_flipped=0;
+
+#ifdef IO_DUMP
+   ioLogFp = fopen("iodump.csv", "wt");
+#endif
 }
 ////////////////////////////////////////////////////////////////////////////////
 //
@@ -172,6 +181,10 @@ void ws_io_done(void)
    {
       free(ws_ioRam);
    }
+
+#ifdef IO_DUMP
+   fclose(ioLogFp);
+#endif
 }
 
 /* Serial port */
@@ -582,6 +595,10 @@ uint8_t cpu_readport(uint8_t port)
 
 
 exit:
+   if (ioLogFp)
+   {
+      fprintf(ioLogFp, "%ld, R, %02X, %02X\n", nec_monotonicCycles, port, retVal);
+   }
    return retVal;
 }
 ////////////////////////////////////////////////////////////////////////////////
@@ -600,6 +617,11 @@ void cpu_writeport(uint32_t port,uint8_t value)
    int unknown_io_port=0;
 
 
+   if (ioLogFp)
+   {
+      fprintf(ioLogFp, "%ld, W, %02X, %02X\n", nec_monotonicCycles, port, value);
+   }
+
    if (port > 0x100)
    {
       port &= 0xFF;
diff --git a/source/nec/nec.cpp b/source/nec/nec.cpp
index ff79ac1..1f4b76f 100644
--- a/source/nec/nec.cpp
+++ b/source/nec/nec.cpp
@@ -38,6 +38,7 @@
 /* cpu state                                                               */
 /***************************************************************************/
 
+uint64_t nec_monotonicCycles;
 int nec_ICount;
 
 nec_Regs I;
@@ -65,6 +66,7 @@ void nec_reset (void *param)
    unsigned int i,j,c;
    BREGS reg_name[8]= { AL, CL, DL, BL, AH, CH, DH, BH };
 
+   nec_monotonicCycles = 0;
 
    memset( &I, 0, sizeof(I) );
 
@@ -3912,7 +3914,7 @@ const char *instructionsName[256] =
 
 int nec_execute(int cycles)
 {
-
+   int done;
 
    nec_ICount=cycles;
 //	cpu_type=V30;
@@ -3928,6 +3930,10 @@ int nec_execute(int cycles)
 //		nec_ICount++;
    }
 
-   return cycles - nec_ICount;
+   done = cycles - nec_ICount;
+
+   nec_monotonicCycles += done;
+
+   return done;
 }