ESPSD Driver Cleanup

- Includes workaround for S100 Z180 SBC data transfer anomaly

Source/HBIOS/espsd.asm

@@ -709,13 +709,11 @@ ESPSD_BLKREAD2:
 	; READ BYTES FAST (NO TIMEOUT CHECK)
 	DEC	C			; BACK TO STATUS PORT
 ESPSD_BLKREAD2A:
-	IN	A,(C)			; GET STATUS		
+#IF (PLATFORM == PLT_S100)
+	IN	A,(C)			; EXTRA READ FOR S100 STABILITY
+#ENDIF
+	IN	A,(C)			; GET STATUS
 	JP	P,ESPSD_BLKREAD2A	; LOOP TILL DATA READY
-	; DOUBLE CHECK STATUS, FIRST READ CAN BE BOGUS
-	;;;IN	A,(C)			; GET STATUS
-	;;;JP	P,ESPSD_BLKREAD2A	; LOOP TILL DATA READY
-	; NOPS NEEDED FOR RELIABILITY
-	;NOP \ NOP \ NOP \ NOP \ NOP \ NOP
 	INC	C			; DATA PORT
 	INI				; GET BYTE, BUMP PTR
 	JR	NZ,ESPSD_BLKREAD2	; 256 TIMES
@@ -765,15 +763,12 @@ ESPSD_BLKWRITE2:
 	; WRITE BYTES FAST (NO TIMEOUT CHECK)
 	DEC	C			; BACK TO STATUS PORT
 ESPSD_BLKWRITE2A:
+#IF (PLATFORM == PLT_S100)
+	IN	A,(C)			; EXTRA READ FOR S100 STABILITY
+#ENDIF
 	IN	A,(C)			; GET STATUS
 	RRA				; SEND RDY BIT TO CF
 	JR	C,ESPSD_BLKWRITE2A	; LOOP WHILE XMIT FULL
-	; DOUBLE CHECK STATUS, FIRST READ CAN BE BOGUS
-	;;;IN	A,(C)			; GET STATUS
-	;;;RRA				; SEND RDY BIT TO CF
-	;;;JR	C,ESPSD_BLKWRITE2A	; LOOP WHILE XMIT FULL
-	; NOPS NEEDED FOR RELIABILITY
-	;NOP \ NOP \ NOP \ NOP \ NOP \ NOP
 	INC	C			; DATA PORT
 	OUTI				; SEND BYTE, BUMP PTR
 	JR	NZ,ESPSD_BLKWRITE2	; 256 TIMES
@@ -813,6 +808,9 @@ ESPSD_PUTBYTE:
 	LD	B,0
 	LD	C,(IY+ESPSD_IOBASE)
 ESPSD_PUTBYTE1:
+#IF (PLATFORM == PLT_S100)
+	IN	A,(C)			; EXTRA READ FOR S100 STABILITY
+#ENDIF
 	IN	A,(C)
 	BIT	0,A
 	JR	Z,ESPSD_PUTBYTE2
@@ -866,14 +864,9 @@ ESPSD_GETBYTE:
 	LD	B,0
 	LD	C,(IY+ESPSD_IOBASE)
 ESPSD_GETBYTE1:
-
-	;;;IN	A,(C)			; FIX BOGUS STATUS READ???
-
-	;;;IN	A,(C)			; *DEBUG*
-	;;;IN	E,(C)                   ; *DEBUG*
-	;;;CP	E                       ; *DEBUG*
-	;;;CALL	NZ,PRTHEXBYTE           ; *DEBUG*
-
+#IF (PLATFORM == PLT_S100)
+	IN	A,(C)			; EXTRA READ FOR S100 STABILITY
+#ENDIF
 	IN	A,(C)
 	JP	M,ESPSD_GETBYTE2
 	DJNZ	ESPSD_GETBYTE1