FDU App Updates

- Improve read/write sector performance in FDU to avoid spurious overrun
errors.
- Fix boot loader under UNA

Doc/FDU.txt

@@ -1,9 +1,9 @@
 ================================================================
-Floppy Disk Utility (FDU) v5.0 for RetroBrew Computers 
+Floppy Disk Utility (FDU) v5.1 for RetroBrew Computers 
 Disk IO / Zeta / Dual-IDE / N8
 ================================================================
 
-Updated September 2, 2017
+Updated December 16, 2017
 by Wayne Warthen (wwarthen@gmail.com)
 
 Application to test the hardware functionality of the Floppy 
@@ -470,4 +470,7 @@ WW 9/2/2017: v5.0
 
 Renamed from FD to FDU.
 Added runtime selection of FDC hardware.
-Added runtime timing adjustment.
+Added runtime timing adjustment.
+
+WW 12/16/2017: v5.1
+Improved polling version of read/write to fix occasional overrun errors.

Source/Apps/FDU/FDU.asm

@@ -37,12 +37,13 @@
 ;   2017-09-02: V5.0	RENAMED APP TO FDU (FLOPPY DISK UTILITY)
 ;			DYNAMIC FDC SELECTION AT STARTUP
 ;			DYNAMIC CPU SPEED ADJUSTMENT
+;   2017-12-16: V5.1	IMPROVED POLLING READ/WRITE PERFORMANCE
 ;			
 ;_______________________________________________________________________________
 ;
 ; BUILDING:
 ;   CAN BE BUILT WITH TASM LIKE THIS:
-;      TASM -t80 -b -fFF FD.ASM FD.COM FD.LST
+;      TASM -t80 -b -fFF FDU.ASM FDU.COM FDU.LST
 ;
 ; TODO:
 ;   1) CURRENT TRACK IS UPDATED EVEN IF SEEK FAILS! (DEFER, RECOVERS AUTOMATICALLY)
@@ -56,8 +57,6 @@
 ;_______________________________________________________________________________
 ;
 ;
-CPUFREQ		.EQU		20		; IN MHZ, USED TO COMPUTE DELAY FACTORS
-;
 FDC_DIO		.EQU		0
 FDC_DIO3	.EQU		1
 FDC_ZETA	.EQU		2
@@ -198,7 +197,7 @@ INIT5:
 	XOR	A
 	RET
 		
-STR_BANNER	.DB	"Floppy Disk Utility (FDU) v5.0, 02-Sep-2017$"
+STR_BANNER	.DB	"Floppy Disk Utility (FDU) v5.1, 16-Dec-2017$"
 STR_BANNER2	.DB	"Copyright (C) 2017, Wayne Warthen, GNU GPL v3","$"
 STR_HBIOS	.DB	" [HBIOS]$"
 STR_UBIOS	.DB	" [UBIOS]$"
@@ -2067,8 +2066,9 @@ FCP_XFRCNT	.DW	00H	; BYTES TRANSFERRED DURING COMMAND PHASE
 ; FDC EXECUTION PHASE
 ;
 FXP_XR		.DW	00H	; INPUT: ADDRESS OF EXECUTION ROUTINE TO INVOKE
-FXP_TO		.DW	00H	; TIMEOUT COUNTDOWN TIMER USED IN SOME VARIATIONS
+FXP_TO		.DB	00H	; TIMEOUT COUNTDOWN TIMER USED IN SOME VARIATIONS
 FXP_XFRCNT	.DW	00H	; BYTES TRANSFERRED DURING EXECUTION
+FXP_ITER	.DB	00H	; LOOP ITERATION WORKING COUNTER
 FXP_A		.DB	00H	; LAST VALUE OF REG A RECORDED DURING EXECUTION
 FXP_BC		.DW	00H	; LAST VALUE OF REG BC RECORDED DURING EXECUTION
 FXP_DE		.DW	00H	; LAST VALUE OF REG DE RECORDED DURING EXECUTION
@@ -2881,18 +2881,19 @@ FOP_X1:
 	LD	HL,(FXP_XR)	; LOAD THE EXECUTION ROUTINE ADDRESS
 	CALL	JPHL		; CALL INDIRECTLY VIA HL
 	
-		; FIX: NEED TO CHECK REG A FOR STATUS, DEPENDING ON STATUS
-		; IT MAY BE NECESSARY TO DO SOMETHING SPECIAL?
-
+	LD	A,(FST_RC)	; CURRENT RESULT CODE
+	CP	FRC_OK		; ERROR?
+	RET	NZ		; IF SO, ALL DONE
+	
 ;	JP	FOP_RES		; CONTINUE WITH GETRESULTS
 	
 ;
 ; RESULTS PHASE
 ;
 FOP_RES:
-	LD	B,0			; D = BYTES RECEIVED
+	LD	B,0			; B = BYTES RECEIVED
 	LD	HL,FRB_LEN		; POINT TO BUFFER LENGTH
-	LD	(HL),D			; UPDATE NUMBER OF BYTES RECEIVED
+	LD	(HL),B			; UPDATE NUMBER OF BYTES RECEIVED
 	LD	HL,FRB			; POINT TO RECEIVE BUFFER
 
 FOP_RES0:
@@ -2903,11 +2904,13 @@ FOP_RES1:
 	CALL	DELAY			; FDC MAY TAKE UP TO 12us TO UPDATE MSR
 	IN	A,(C)			; READ MAIN STATUS REGISTER
 	LD	(FST_MSR),A		; SAVE IT FOR POTENTIAL LATER DIAGNOSIS
-	AND	0F0H			; ISOLATE RQM/DIO
+	AND	0F0H			; REMOVE SEEK BITS
 	CP	0D0H			; LOOKING FOR RQM=1, DIO=1, BUSY=1 (FDC BYTE PENDING)
-	JP	Z,FOP_RES2		; GOOD, GO TO RECEIVE BYTE
-	CP	080H			; CHECK FOR RQM=1, DIO=0 (NOTHING LEFT)
-	JP	Z,FOP_EVAL		; IF NOTHING, ALL DONE, LEFT GO TO EOD/EXIT
+	JR	Z,FOP_RES2		; GOOD, GO TO RECEIVE BYTE
+	CP	$80			; DONE?
+	JR	Z,FOP_EVAL		; IF SO, GO TO EVAL
+	;CALL	PC_SPACE
+	;CALL	PRTHEXBYTE
 	DEC	DE
 	LD	A,D
 	OR	E
@@ -3156,45 +3159,45 @@ FXRX1:
 	JR	NZ,FXRX1		; NOT ZERO YET, KEEP CHECKING
 	JP	FXR_TO			; OTHERWISE, TIMEOUT ERROR
 	RET
+
 ;
 ; READ DATA
 ;
-FXRR:
-	DI				; DISABLE INTERRUPTS TO AVOID TIMEOUTS
-	LD	A,(CPUFREQ + 3) / 4	; HIGH BYTE OF OUTER LOOP COUNTER
-	LD	(FXP_TO+1),A		; SAVE HIGH BYTE OF COUNTER
-	XOR	A			; LOW BYTE IS ZERO
-	LD	(FXP_TO),A		; SAVE LOW BYTE
-	LD	B,A			; INIT INNER LOOP COUNTER
-	LD	C,(IY+CFG_MSR)		; SET C TO MSR PORT
-FXRR1:	LD	B,0			; SETUP FOR 256 ITERATIONS (INNER LOOP)
-	; INNER LOOP
-FXRR2:	IN	A,(C)			; GET MSR
-	CP	0F0H			; WE WANT RQM=1,DIO=1,EXM=1,BUSY=1 (READY TO RECEIVE A BYTE W/ EXEC ACTIVE)
-	JP	Z,FXRR3			; GOT IT, DO BYTE READ
-	DJNZ	FXRR2			; NOT READY, LOOP IF COUNTER NOT ZERO
-	; OUTER LOOP
-	AND	0E0H			; MASK TO ISOLATE RQM, DIO, EXM
-	CP	0C0H			; IF RQM=1, DIO=1, EXM=0 (EXECUTION ABORTED)
-	JP	Z,FXR_ABORT		; IF ZERO, BAIL OUT TO ERR ROUTINE, FIX: GO TO SPECIFIC ROUTINE FOR THIS???
-	PUSH	HL			; SAVE HL
-	LD	HL,(FXP_TO)		; GET DOWN COUNTER
-	DEC	HL			; DECREMENT
-	LD	(FXP_TO),HL		; SAVE IT
-	LD	A,L			; CHECK COUNTER
-	OR	H			; ... FOR ZERO
-	POP	HL			; RESTORE HL
-	JR	NZ,FXRR1		; LOOP IF NOT ZERO
-	JP	FXR_TO			; OTHERWISE, TIMEOUT
-FXRR3:	; READ A PENDING BYTE
-	INC	C			; SET C TO DATA PORT
-	INI				; READ PORT C TO (HL) AND INC HL
-	DEC	C			; SET C BACK TO STATUS PORT
-	DEC	DE			; DECREMENT BYTE COUNT
-	LD	A,D			; TEST COUNTER
-	OR	E			; ... FOR ZERO
-	JP	NZ,FXRR1		; IF NOT ZERO, REPEAT LOOP
-	JP	FXR_END			; CLEAN EXIT
+FXRR:	LD	A,E			; LOW BYTE OF COUNT TO ACCUM
+	OR	A			; TEST FOR ZERO
+	JR	Z,FXRR1			; IF ZERO, DO NOT ADJUST ITERATIONS
+	INC	D			; OTHERWISE, ITERATIONS IS ONE MORE THAN HIGH BYTE
+FXRR1:	LD	B,E			; LOW BYTE OF COUNT TO B
+	LD	A,D			; HIGH BYTE OF COUNT
+	LD	(FXP_ITER),A		; ... IS ITERATION COUNT
+	LD	IX,FXP_ITER		; SETUP IX AS POINTER TO ITERATION COUNT
+	LD	A,(CPUSPD)		; CPU SPEED SCALER
+	LD	(FXP_TO),A		; SAVE IT AS OUTER LOOP TIMEOUT
+	LD	C,(IY+CFG_DATA)		; SET C TO DATA PORT
+	DI				; DISABLE INTERRUPTS TO AVOID OVERRUN
+FXRR2:	DEC	C			; [04] SET C TO MSR PORT
+FXRR3:	LD	DE,0			; [10] TIMEOUT COUNTER
+FXRR4:	IN	A,(C)			; [12] GET MSR
+	CP	$F0			; [07] BYTE READY?
+	JR	Z,FXRR5			; [12/7] GET IT
+	;LD	(FST_MSR),A		; [13] *DEBUG* SAVE MSR FOR LATER
+	DEC	E			; [04] DEC LSB OF INNER TIMEOUT COUNTER
+	JR	NZ,FXRR4		; [12/7] LOOP IF LSB IS NOT EXHAUSTED
+	CP	$D0			; [07] IF RQM=1, DIO=1, EXM=0, CB=1, EXECUTION ABORTED
+	JP	Z,FXR_ABORT		; [10] IF NOT SET, EXECUTION ABORTED
+	DEC	D			; [04] DEC MSB OF INNER TIMEOUT COUNTER
+	JR	NZ,FXRR4		; [12/7] LOOP IF MSB IS NOT EXHAUSTED
+	LD	A,(FXP_TO)		; [13] GET OUTER LOOP COUNTER
+	DEC	A			; [04] DECREMENT
+	LD	(FXP_TO),A		; [13] SAVE NEW COUNTER VALUE
+	JR	NZ,FXRR3		; [12/7] LOOP IF NOT EXHAUSTED
+	JP	FXR_TO			; [10] OTHERWISE, HANDLE TIMEOUT
+FXRR5:	INC	C			; [04] POINT TO DATA PORT
+	INI				; [16] (HL) := (C), HL++, B--
+	JR	NZ,FXRR2		; [12/7] LOOP
+	DEC	(IX)			; [23] DECREMENT ITERATION COUNT
+	JR	NZ,FXRR2		; [12] IF MORE ITERATIONS, GO DO IT
+	JP	FXR_END			; [10] ELSE DONE
 
 ;
 ; INT READ DATA - SAFE VERSION
@@ -3265,42 +3268,42 @@ WFXRR2:
 ;
 ; WRITE DATA
 ;
-FXRW:
-	DI				; DISABLE INTERRUPTS TO AVOID TIMEOUTS
-	LD	A,(CPUFREQ + 3) / 4	; HIGH BYTE OF OUTER LOOP COUNTER
-	LD	(FXP_TO+1),A		; SAVE HIGH BYTE OF COUNTER
-	XOR	A			; LOW BYTE IS ZERO
-	LD	(FXP_TO),A		; SAVE LOW BYTE
-	LD	B,A			; INIT INNER LOOP COUNTER
-	LD	C,(IY+CFG_MSR)		; SET C TO MSR PORT
-FXRW1:	LD	B,0			; SETUP FOR 256 ITERATIONS
-	; INNER LOOP
-FXRW2:	IN	A,(C)			; GET MSR
-	CP	0B0H			; WE WANT RQM=1,DIO=0,EXM=1,BUSY=1 (READY TO SEND A BYTE W/ EXEC ACTIVE)
-	JR	Z,FXRW3			; GOT IT, DO BYTE WRITE
-	DJNZ	FXRW2			; NOT READY, LOOP IF COUNTER NOT ZERO
-	; OUTER LOOP
-	AND	0E0H			; MASK TO ISOLATE RQM, DIO, EXM
-	CP	0C0H			; IF RQM=1, DIO=1, EXM=0 (EXECUTION ABORTED)
-	JP	Z,FXR_ABORT		; IF ZERO, BAIL OUT TO ERR ROUTINE, FIX: GO TO SPECIFIC ROUTINE FOR THIS???
-	PUSH	HL			; SAVE HL
-	LD	HL,(FXP_TO)		; GET DOWN COUNTER
-	DEC	HL			; DECREMENT
-	LD	(FXP_TO),HL		; SAVE IT
-	LD	A,L			; CHECK COUNTER
-	OR	H			; ... FOR ZERO
-	POP	HL			; RESTORE HL
-	JR	NZ,FXRW1		; LOOP IF NOT ZERO
-	JP	FXR_TO			; OTHERWISE, TIMEOUT
-FXRW3:	; READ A PENDING BYTE
-	INC	C			; SET C TO DATA PORT
-	OUTI				; WRITE (HL) TO PORT C AND INC HL
-	DEC	C			; SET C BACK TO STATUS PORT
-	DEC	DE			; DECREMENT LOOP COUNTER
-	LD	A,D			; TEST COUNTER
-	OR	E			; ... FOR ZERO
-	JP	NZ,FXRW1		; IF NOT ZERO, REPEAT LOOP
-	JP	FXR_END			; CLEAN EXIT
+FXRW:	LD	A,E			; LOW BYTE OF COUNT TO ACCUM
+	OR	A			; TEST FOR ZERO
+	JR	Z,FXRW1			; IF ZERO, DO NOT ADJUST ITERATIONS
+	INC	D			; OTHERWISE, ITERATIONS IS ONE MORE THAN HIGH BYTE
+FXRW1:	LD	B,E			; LOW BYTE OF COUNT TO B
+	LD	A,D			; HIGH BYTE OF COUNT
+	LD	(FXP_ITER),A		; ... IS ITERATION COUNT
+	LD	IX,FXP_ITER		; SETUP IX AS POINTER TO ITERATION COUNT
+	LD	A,(CPUSPD)		; CPU SPEED SCALER
+	LD	(FXP_TO),A		; SAVE IT AS OUTER LOOP TIMEOUT
+	LD	C,(IY+CFG_DATA)		; SET C TO DATA PORT
+	DI				; DISABLE INTERRUPTS TO AVOID OVERRUN
+FXRW2:	DEC	C			; [04] SET C TO MSR PORT
+FXRW3:	LD	DE,0			; [10] TIMEOUT COUNTER
+FXRW4:	IN	A,(C)			; [12] GET MSR
+	CP	$B0			; [07] BYTE READY?
+	JR	Z,FXRW5			; [12/7] GET IT
+	;LD	(FST_MSR),A		; [13] *DEBUG* SAVE MSR FOR LATER
+	DEC	E			; [04] DEC LSB OF INNER TIMEOUT COUNTER
+	JR	NZ,FXRW4		; [12/7] LOOP IF LSB IS NOT EXHAUSTED
+	CP	$D0			; [07] IF RQM=1, DIO=1, EXM=0, CB=1, EXECUTION ABORTED
+	JP	Z,FXR_ABORT		; [10] IF NOT SET, EXECUTION ABORTED
+	DEC	D			; [04] DEC MSB OF INNER TIMEOUT COUNTER
+	JR	NZ,FXRW4		; [12/7] LOOP IF MSB IS NOT EXHAUSTED
+	LD	A,(FXP_TO)		; [13] GET OUTER LOOP COUNTER
+	DEC	A			; [04] DECREMENT
+	LD	(FXP_TO),A		; [13] SAVE NEW COUNTER VALUE
+	JR	NZ,FXRW3		; [12/7] LOOP IF NOT EXHAUSTED
+	JP	FXR_TO			; [10] OTHERWISE, HANDLE TIMEOUT
+FXRW5:	INC	C			; [04] POINT TO DATA PORT
+	OUTI				; [16] (C) := (HL), HL++, B--
+	JR	NZ,FXRW2		; [12/7] LOOP
+	DEC	(IX)			; [23] DECREMENT ITERATION COUNT
+	JR	NZ,FXRW2		; [12] IF MORE ITERATIONS, GO DO IT
+	JP	FXR_END			; [10] ELSE DONE
+
 
 ;
 ; INT WRITE DATA - SAFE VERSION
@@ -3369,34 +3372,41 @@ WFXRW2:
 ;
 
 FXR_TO:
+	; SET ERROR AND GET OUT W/O PULSING TC
 	LD	A,FRC_TOEXEC
-	JP	FXR_ERR
+	LD	(FST_RC),A
+	JR	FXR_END2
 
 FXR_ABORT:
-	LD	A,FRC_ABORT
-	JP	FXR_ERR
-FXR_ERR:
-	LD	(FST_RC),A
-	JP	FXR_END2
+	; LET RESULTS PHASE HANDLE ERROR, DO NOT PULSE TC, COMMAND ALREADY TERMINATED
+	;LD	A,FRC_ABORT
+	;LD	(FST_RC),A
+	JR	FXR_END2
 
 FXR_END:
-	; DO NOT PULSE TC AT END OF FORMAT
+	; DO NOT PULSE TC AT END OF FORMAT OR READID, THOSE COMMANDS SELF-TERMINATE
 	LD	A,(FCP_CMD)
 	CP	CMD_FMTTRK
 	JR	Z,FXR_END2
-
-	; DO NOT PULSE TC AT END OF READID
 	CP	CMD_READID
 	JR	Z,FXR_END2
-
+	
 	CALL	FC_PULSETC
-
+	
 FXR_END2:
+#IF 0
 	LD	(FXP_A),A
 	LD	(FXP_BC),BC
 	LD	(FXP_DE),DE
 	LD	(FXP_HL),HL
 
+	LD	C,(IY+CFG_MSR)		; SET C TO MSR PORT
+	IN	A,(C)
+	LD	(FST_MSR),A
+	
+	CALL	FXR_DUMP
+#ENDIF
+	
 	EI				; I/O FINISHED, INTS BACK ON
 	RET
 
@@ -3562,6 +3572,12 @@ FXR_DUMP:
 	CALL	WRITESTR
 	LD	A,(FST_MSR)
 	CALL	PRTHEXBYTE
+	
+	LD	DE,STR_A
+	CALL	WRITESTR
+	LD	A,(FXP_A)
+	CALL	PRTHEXBYTE
+	
 	LD	DE,STR_BC
 	CALL	WRITESTR
 	LD	BC,(FXP_BC)
@@ -3569,6 +3585,7 @@ FXR_DUMP:
 	CALL	PRTHEXBYTE
 	LD	A,C
 	CALL	PRTHEXBYTE
+
 	LD	DE,STR_DE
 	CALL	WRITESTR
 	LD	BC,(FXP_DE)
@@ -3576,6 +3593,7 @@ FXR_DUMP:
 	CALL	PRTHEXBYTE
 	LD	A,C
 	CALL	PRTHEXBYTE
+
 	LD	DE,STR_HL
 	CALL	WRITESTR
 	LD	BC,(FXP_HL)
@@ -3583,6 +3601,17 @@ FXR_DUMP:
 	CALL	PRTHEXBYTE
 	LD	A,C
 	CALL	PRTHEXBYTE
+
+	LD	DE,STR_ITER
+	CALL	WRITESTR
+	LD	A,(FXP_ITER)
+	CALL	PRTHEXBYTE
+
+	LD	DE,STR_TO
+	CALL	WRITESTR
+	LD	A,(FXP_TO)
+	CALL	PRTHEXBYTE
+
 	RET
 ;
 ; DOR BITS (3AH)									
@@ -3823,17 +3852,16 @@ COPYSTR:
 ;	PRINT CONTENTS OF A 
 ;________________________________________________________________________________________________________________________________
 ;
-COUT_BUFFER	.TEXT	" $"
-;
 COUT:
 	PUSH	BC			;
 	PUSH	AF			;
 	PUSH	HL			;
 	PUSH	DE			;
-	LD	(COUT_BUFFER),A		;
-	LD	DE,COUT_BUFFER		;
-	LD	C,09H			; CP/M WRITE START STRING TO CONSOLE CALL
-	CALL	0005H
+
+	LD	C,2			; BDOS FUNC: CONSOLE WRITE CHAR
+	LD	E,A			; CHARACTER TO E
+	CALL	$0005			; CALL BDOS
+	
 	POP	DE			;
 	POP	HL			;
 	POP	AF			;
@@ -4403,9 +4431,12 @@ STR_SN		.TEXT	" SN=$"
 STR_NCN		.TEXT	" NCN=$"
 STR_PCN		.TEXT	" PCN=$"
 STR_MSR		.TEXT	" MSR=$"
+STR_A		.TEXT	" A=$"
 STR_BC		.TEXT	" BC=$"
 STR_DE		.TEXT	" DE=$"
 STR_HL		.TEXT	" HL=$"
+STR_TO		.TEXT	" TO=$"
+STR_ITER	.TEXT	" ITER=$"
 STR_DSKCHG	.TEXT	" DC=$"
 ;
 KEYBUFLEN	.EQU	80

Source/Apps/FDU/FDU.txt

@@ -1,9 +1,9 @@
 ================================================================
-Floppy Disk Utility (FDU) v5.0 for RetroBrew Computers 
+Floppy Disk Utility (FDU) v5.1 for RetroBrew Computers 
 Disk IO / Zeta / Dual-IDE / N8
 ================================================================
 
-Updated September 2, 2017
+Updated December 16, 2017
 by Wayne Warthen (wwarthen@gmail.com)
 
 Application to test the hardware functionality of the Floppy 
@@ -470,4 +470,7 @@ WW 9/2/2017: v5.0
 
 Renamed from FD to FDU.
 Added runtime selection of FDC hardware.
-Added runtime timing adjustment.
+Added runtime timing adjustment.
+
+WW 12/16/2017: v5.1
+Improved polling version of read/write to fix occasional overrun errors.

Source/HBIOS/hbios.asm

@@ -603,10 +603,12 @@ HB_START:
 	XOR	A
 	OUT0	(Z180_CCR),A
 	OUT0	(Z180_CMR),A
+	CALL	DLY8			; SETTLE
 
 	; SET DEFAULT WAIT STATES
 	LD	A,$F0
 	OUT0	(Z180_DCNTL),A
+	CALL	DLY8			; SETTLE
 
  	; MMU SETUP
  	LD	A,$80	
@@ -622,12 +624,14 @@ HB_START:
 	; SET CLOCK DIVIDE TO 1 RESULTING IN FULL XTAL SPEED
 	LD	A,$80
 	OUT0	(Z180_CCR),A
+	CALL	DLY8			; SETTLE
 #ENDIF
 
 #IF (Z180_CLKDIV >= 2)
 	; SET CPU MULTIPLIER TO 1 RESULTING IN XTAL * 2 SPEED
 	LD	A,$80
 	OUT0	(Z180_CMR),A
+	CALL	DLY8			; SETTLE
 #ENDIF
 
 #ENDIF
@@ -651,10 +655,29 @@ HB_START:
 ;
 ; INSTALL PROXY IN UPPER MEMORY
 ;
+
+;X1	.EQU	$8000
+;X2	.EQU	X1 + 2
+;X3	.EQU	X2 + 2
+;X4	.EQU	X3 + 2
+	
+;	LD	HL,(HBX_IMG)
+;	LD	(X1),HL
+
+;	LD	HL,(HBX_IMG)
+;	LD	(X2),HL
+
 	LD	HL,HBX_IMG
 	LD	DE,HBX_LOC
 	LD	BC,HBX_SIZ
 	LDIR
+
+;	LD	HL,(HBX_IMG)
+;	LD	(X3),HL
+
+;	LD	HL,(HBX_LOC)
+;	LD	(X4),HL
+
 ;
 ; IF ALREADY EXECUTING IN RAM, BYPASS RAM BANK INSTALLATION
 ;
@@ -747,6 +770,23 @@ HB_START1:			; BNKCALL ARRIVES HERE, BUT NOW RUNNING IN RAM BANK
 ;
 	CALL	NEWLINE2
 	PRTX(STR_BANNER)
+	
+;	CALL	PC_SPACE
+;	LD	BC,(X1)
+;	CALL	PRTHEXWORD
+	
+;	CALL	PC_SPACE
+;	LD	BC,(X2)
+;	CALL	PRTHEXWORD
+	
+;	CALL	PC_SPACE
+;	LD	BC,(X3)
+;	CALL	PRTHEXWORD
+
+;	CALL	PC_SPACE
+;	LD	BC,(X4)
+;	CALL	PRTHEXWORD
+
 ;
 ; IO PORT SCAN
 ;