From 4eebc6c7f6e391f3325cc978050053ec3e5795b3 Mon Sep 17 00:00:00 2001
From: Peter Veenstra <qbix79@users.sourceforge.net>
Date: Sun, 11 Sep 2005 13:04:21 +0000
Subject: [PATCH] add patch 1240134 from cyberwalker. (initialize some
 registers). Report a periodic interrupt occured when the timer is active and
 one occurs(status reg 0xC). Fixes contraption Zack and friends

Imported-from: https://svn.code.sf.net/p/dosbox/code-0/dosbox/trunk@2307
---
 src/hardware/cmos.cpp | 28 +++++++++++++++++++++-------
 1 file changed, 21 insertions(+), 7 deletions(-)

diff --git a/src/hardware/cmos.cpp b/src/hardware/cmos.cpp
index c7ade821..3ee978ef 100644
--- a/src/hardware/cmos.cpp
+++ b/src/hardware/cmos.cpp
@@ -46,7 +46,10 @@ static struct {
 
 static void cmos_timerevent(Bitu val) {
 	PIC_ActivateIRQ(8); 
-	if (cmos.timer.enabled) PIC_AddEvent(cmos_timerevent,cmos.timer.delay);
+	if (cmos.timer.enabled) {
+		PIC_AddEvent(cmos_timerevent,cmos.timer.delay);
+		cmos.regs[0xc] = 0xC0;//Contraption Zack (music)
+	}
 }
 
 static void cmos_checktimer(void) {
@@ -94,6 +97,9 @@ static void cmos_writereg(Bitu port,Bitu val,Bitu iolen) {
 		if (val&0x10) LOG(LOG_BIOS,LOG_ERROR)("CMOS:Updated ended interrupt not supported yet");
 		cmos_checktimer();
 		break;
+	case 0x0d:/* Status reg D */
+		cmos.regs[cmos.reg]=val & 0x80;	/*Bit 7=1:RTC Pown on*/
+		break;
 	case 0x0f:		/* Shutdown status byte */
 		cmos.regs[cmos.reg]=val & 0x7f;
 		break;
@@ -115,7 +121,6 @@ static Bitu cmos_readreg(Bitu port,Bitu iolen) {
 	Bit8u hdparm;
 	time_t curtime;
 	struct tm *loctime;
-
 	/* Get the current time. */
 	curtime = time (NULL);
 
@@ -143,7 +148,7 @@ static Bitu cmos_readreg(Bitu port,Bitu iolen) {
 	case 0x03:		/* Minutes Alarm */
 	case 0x05:		/* Hours Alarm */
 		return cmos.regs[cmos.reg];
-	case 0x0a:		/* Status register C */
+	case 0x0a:		/* Status register A */
 		if (PIC_TickIndex()<0.002) {
 			return (cmos.regs[0x0a]&0x7f) | 0x80;
 		} else {
@@ -249,21 +254,24 @@ static Bitu cmos_readreg(Bitu port,Bitu iolen) {
 
 
 	case 0x0b:		/* Status register B */
+	case 0x0d:		/* Status register D */
 	case 0x0f:		/* Shutdown status byte */
+	case 0x14:		/* Equipment */
+	case 0x15:		/* Base Memory KB Low Byte */
+	case 0x16:		/* Base Memory KB High Byte */
 	case 0x17:		/* Extended memory in KB Low Byte */
 	case 0x18:		/* Extended memory in KB High Byte */
 	case 0x30:		/* Extended memory in KB Low Byte */
 	case 0x31:		/* Extended memory in KB High Byte */
-//		LOG(LOG_BIOS,LOG_NORMAL)("CMOS:Read from reg %F : %04X",cmos.reg,cmos.regs[cmos.reg]);
+//		LOG(LOG_BIOS,LOG_NORMAL)("CMOS:Read from reg %X : %04X",cmos.reg,cmos.regs[cmos.reg]);
 		return cmos.regs[cmos.reg];
 	default:
-		LOG(LOG_BIOS,LOG_NORMAL)("CMOS:Read from reg %F",cmos.reg);
+		LOG(LOG_BIOS,LOG_NORMAL)("CMOS:Read from reg %X",cmos.reg);
 		return cmos.regs[cmos.reg];
 	}
 }
 
-void CMOS_SetRegister(Bitu regNr, Bit8u val)
-{
+void CMOS_SetRegister(Bitu regNr, Bit8u val) {
 	cmos.regs[regNr] = val;
 };
 
@@ -282,6 +290,12 @@ public:
 		cmos_writereg(0x71,0x26,1);
 		cmos.reg=0xb;
 		cmos_writereg(0x71,0x2,1);	//Struct tm *loctime is of 24 hour format,
+		cmos.reg=0xd;
+		cmos_writereg(0x71,0x80,1); /* RTC power on */
+		// Equipment is updated from bios.cpp and bios_disk.cpp
+		/* Fill in base memory size, it is 640K always */
+		cmos.regs[0x15]=(Bit8u)0x80;
+		cmos.regs[0x16]=(Bit8u)0x02;
 		/* Fill in extended memory size */
 		Bitu exsize=(MEM_TotalPages()*4)-1024;
 		cmos.regs[0x17]=(Bit8u)exsize;