From af3401ac5bb349f0aad004126291c4cfc7dba34e Mon Sep 17 00:00:00 2001
From: Martin Giese <martingi@ifi.uio.no>
Date: Tue, 8 Jul 2025 21:24:38 +0200
Subject: [PATCH] 1 bit speaker code refecatored to arbitrary ports and masks

---
 Source/HBIOS/cfg_MASTER.asm |  3 +++
 Source/HBIOS/spk.asm        | 31 ++++++++++++++++++-------------
 2 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/Source/HBIOS/cfg_MASTER.asm b/Source/HBIOS/cfg_MASTER.asm
index 52cd1635..fd8ff97d 100644
--- a/Source/HBIOS/cfg_MASTER.asm
+++ b/Source/HBIOS/cfg_MASTER.asm
@@ -463,6 +463,9 @@ AYMODE		.EQU	AYMODE_NONE	; AY: DRIVER MODE: AYMODE_[SCG|N8|RCZ80|RCZ180|MSX|LINC
 AY_FORCE	.EQU	FALSE		; AY: BYPASS AUTO-DETECT, FORCED PRESENT
 ;
 SPKENABLE	.EQU	FALSE		; SPK: ENABLE RTC LATCH IOBIT SOUND DRIVER (SPK.ASM)
+SPKPORT		.EQU	RTCIO		; SPK: THE PORT WITH THE SPEAKER IO BIT
+SPKSHADOW	.EQU	HB_RTCVAL	; SPK: THE SHADOW VALUE FOR THE PORT THAT HAS TO BE MAINTAINED
+SPKMASK		.EQU	00000100b	; SPK: THE BIT MASK TO ACTUALLY TOGGLE
 ;
 DMAENABLE	.EQU	FALSE		; DMA: ENABLE DMA DRIVER (DMA.ASM)
 DMABASE		.EQU	$E0		; DMA: DMA BASE ADDRESS
diff --git a/Source/HBIOS/spk.asm b/Source/HBIOS/spk.asm
index 3ceb148c..96788f4b 100644
--- a/Source/HBIOS/spk.asm
+++ b/Source/HBIOS/spk.asm
@@ -32,9 +32,7 @@ SP_IDAT	.EQU	0			; NO INSTANCE DATA ASSOCIATED WITH THIS DEVICE
 ;
 SP_TONECNT	.EQU	1		; COUNT NUMBER OF TONE CHANNELS
 SP_NOISECNT	.EQU	0		; COUNT NUMBER OF NOISE CHANNELS
-;
-SP_RTCIOMSK	.EQU	00000100B
-;
+
 ; FOR OTHER DRIVERS, THE PERIOD VALUE FOR THE TONE IS STORED AT PENDING_PERIOD
 ; FOR THE SPK DRIVER THE ADDRESS IN THE TONE TABLE IS STORED IN PENDING_PERIOD
 ;
@@ -43,9 +41,12 @@ SP_PENDING_VOLUME	.DB	0		; PENDING VOL (8 BITS)
 SP_PENDING_DURATION	.DW	0		; PENDING DURATION (16 BITS)
 SP_TBLRDY		.DB	0		; IF != 0, NOTE TABLE IS READY
 ;
-	DEVECHO	"SPK: IO="
-	DEVECHO	RTCIO
-	DEVECHO	"\n"
+	DEVECHO "SPK: IO="
+	DEVECHO SPKPORT
+	DEVECHO " MASK="
+	DEVECHO SPKMASK
+	DEVECHO "\n"
+
 ;
 ;======================================================================
 ;	DRIVER INITIALIZATION
@@ -59,9 +60,12 @@ SP_INIT:
 ;
 	CALL	NEWLINE			; ANNOUNCE DEVICE
 	PRTS("SPK: IO=0x$")
-	LD	A,RTCIO
+	LD	A,SPKPORT
 	CALL	PRTHEXBYTE
-;
+	PRTS(" MASK=0x$")
+	LD	A,SPKMASK
+	CALL	PRTHEXBYTE
+				;
 	CALL	SP_SETTBL		; SETUP TONE TABLE
 	CALL	SP_RESET		; RESET PARAMETERS
 ;
@@ -165,7 +169,7 @@ SP_QUERY_VOLUME:
 ;
 SP_QUERY_DEV:
 	LD	B, SNDDEV_BITMODE		; RETURN DEVICE IDENTIFIER
-	LD	DE, (RTCIO*256)+SP_RTCIOMSK	; AND ADDRESS AND DATA PORT
+	LD	DE, (SPKPORT*256)+SPKMASK	; AND ADDRESS AND DATA PORT
 	XOR	A
 	RET
 ;
@@ -283,7 +287,7 @@ SP_BEEPER:
 	LD	B,$00
 	LD	IX,SPK_DLYADJ 		; The base address of the timing loop.
 	ADD	IX,BC			; Alter the length of the timing loop. Use an earlier starting point for each '1' lost by taking INT (L/4).
-	LD	A,(HB_RTCVAL)		; Fetch the present border colour from BORDCR and move it to bits 2, 1 and 0 of the A register.
+	LD	A,(SPKSHADOW)		; Fetch the present border colour from BORDCR and move it to bits 2, 1 and 0 of the A register.
 ;
 ;	The HL register holds the 'length of the timing loop' with 16 T states being used for each '1' in the L register and 1024 T states for each '1' in the H register.
 ;
@@ -302,8 +306,9 @@ BE_H_L_LP:
 ;
 ;	The loudspeaker is now alternately activated and deactivated.
 ;
-	XOR	SP_RTCIOMSK		; Flip bit 2.
-	OUT	(RTCIO),A		; Perform the 'OUT' operation, leaving other bits unchanged.
+	XOR	SPKMASK			; Flip bit.
+	OUT	(SPKPORT),A		; Perform the 'OUT' operation, leaving other bits unchanged.
+
 	LD	B,H			; Reset the B register.
 	LD	C,A			; Save the A register.
 	BIT	4,A 			; Jump if at the half-cycle point.
@@ -333,7 +338,7 @@ BE_END:
 ;	leaves the bit set to the opposite value it started at.  This
 ;	ensures that the bit is properly reset to its original value.
 ;
-	LD	A,(HB_RTCVAL)		; Get the current RTC latch value
+	LD	A,(SPKSHADOW)		; Get the current RTC latch value
 	OUT	(RTCIO),A		; Set it
 ;
 	RET				; ALWAYS EXITS WITH SUCCESS STATUS (A=0)