From f640630a0676072a74d118a3a4bf27fdb988b979 Mon Sep 17 00:00:00 2001
From: Wayne Warthen <wwarthen@gmail.com>
Date: Mon, 10 Apr 2023 16:20:12 -0700
Subject: [PATCH] CPU Speed Calc Tweek

- Exit CPU speed detection routine earlier if the clock is not ticking.
- Fix minor regression in the SBC_simh.asm config file.
---
 Source/HBIOS/Config/SBC_simh.asm |  3 +++
 Source/HBIOS/hbios.asm           | 10 ++++++++--
 Source/ver.inc                   |  2 +-
 Source/ver.lib                   |  2 +-
 Tools/simh/Sim.cmd               |  5 +++--
 5 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/Source/HBIOS/Config/SBC_simh.asm b/Source/HBIOS/Config/SBC_simh.asm
index 2ee17a8b..328d6eed 100644
--- a/Source/HBIOS/Config/SBC_simh.asm
+++ b/Source/HBIOS/Config/SBC_simh.asm
@@ -30,6 +30,9 @@ INTMODE		.SET	1		; INTERRUPTS: 0=NONE, 1=MODE 1, 2=MODE 2
 ;
 HTIMENABLE	.SET	TRUE		; ENABLE SIMH TIMER SUPPORT
 ;
+SIMRTCENABLE	.SET	TRUE		; ENABLE SIMH CLOCK DRIVER (SIMRTC.ASM)
+DSRTCENABLE	.SET	FALSE		; DSRTC: ENABLE DS-1302 CLOCK DRIVER (DSRTC.ASM)
+;
 UARTENABLE	.SET	TRUE		; UART: ENABLE 8250/16550-LIKE SERIAL DRIVER (UART.ASM)
 UARTSBCFORCE	.SET	TRUE		; UART: FORCE DETECTION OF SBC UART (FOR SIMH)
 ;
diff --git a/Source/HBIOS/hbios.asm b/Source/HBIOS/hbios.asm
index 1a221d76..e40a1533 100644
--- a/Source/HBIOS/hbios.asm
+++ b/Source/HBIOS/hbios.asm
@@ -6286,13 +6286,18 @@ HB_CPUSPD1:
   #ENDIF
 
 	; WAIT FOR AN INITIAL TICK TO ALIGN, THEN WAIT
-	; FOR SECOND TICK AND TO GET A FULL ONE SECOND LOOP COUNT
+	; FOR A SECOND TICK TO GET A FULL ONE SECOND LOOP COUNT.
+	; WAITSEC WILL SET ZF IF AN OVERFLOW OCCURS (MEANING THAT THE
+	; CLOCK IS NOT TICKING).  THERE IS NO
+	; POINT IN CALLING HB_WAITSEC AGAIN IN THAT CASE, SO WE ONLY
+	; CALL HB_WAITSEC AGAIN IF ZF IS NOT SET.
 	CALL	DSRTC_START
 	CALL	HB_RDSEC		; GET SECONDS
 	LD	(HB_CURSEC),A		; AND INIT CURSEC
 	CALL	HB_WAITSEC		; WAIT FOR SECONDS TICK
 	LD	(HB_CURSEC),A		; SAVE NEW VALUE
-	CALL	HB_WAITSEC		; WAIT FOR SECONDS TICK
+	; CALL HB_WAITSEC AGAIN, BUT ONLY IF ZF IS NOT SET
+	CALL	NZ,HB_WAITSEC		; WAIT FOR SECONDS TICK
 ;
   #IF (CPUFAM == CPU_Z180)
 	; RESTORE W/S SETTINGS FROM BEFORE TEST
@@ -6323,6 +6328,7 @@ HB_CPUSPD1:
 HB_WAITSEC:
 	; WAIT FOR SECONDS TICK
 	; RETURN SECS VALUE IN A, LOOP COUNT IN DE
+	; ZF IS SET ON OVERFLOW (CLOCK NOT TICKING)
 	LD	DE,0			; INIT LOOP COUNTER
 HB_WAITSEC1:
 ;
diff --git a/Source/ver.inc b/Source/ver.inc
index 703a4e69..9116b4a7 100644
--- a/Source/ver.inc
+++ b/Source/ver.inc
@@ -2,7 +2,7 @@
 #DEFINE	RMN	2
 #DEFINE	RUP	1
 #DEFINE	RTP	0
-#DEFINE BIOSVER	"3.2.1-rc.1"
+#DEFINE BIOSVER	"3.2.1-rc.2"
 #define rmj	RMJ
 #define rmn	RMN
 #define rup	RUP
diff --git a/Source/ver.lib b/Source/ver.lib
index def1da94..394a574e 100644
--- a/Source/ver.lib
+++ b/Source/ver.lib
@@ -3,5 +3,5 @@ rmn	equ	2
 rup	equ	1
 rtp	equ	0
 biosver	macro
-	db	"3.2.1-rc.1"
+	db	"3.2.1-rc.2"
 	endm
diff --git a/Tools/simh/Sim.cmd b/Tools/simh/Sim.cmd
index ba1c2f70..3e501ab8 100644
--- a/Tools/simh/Sim.cmd
+++ b/Tools/simh/Sim.cmd
@@ -2,8 +2,9 @@
 set ROM=..\..\Binary\SBC_simh.rom
 if not "%1"=="" set ROM=..\..\Binary\%1.rom
 if not exist %ROM% goto romerr
-rem start C:\Users\WWarthen\Bin\putty.exe -load "SIMH Telnet"
-start /w altairz80.exe sim.cfg %ROM%
+:: start C:\Users\WWarthen\Bin\putty.exe -load "SIMH Telnet"
+:: start /w altairz80.exe sim.cfg %ROM%
+altairz80.exe sim.cfg %ROM%
 goto :eof
 
 :romerr