Finalize ROM-Less Booting

ReadMe.md

@@ -3,7 +3,7 @@
 ## Z80/Z180 System Software
 
 Version 3.1 Pre-release  
-28 Feb 2022
+21 Mar 2022
 
 Wayne Warthen <wwarthen@gmail.com>
 

ReadMe.txt

@@ -1,6 +1,6 @@
 RomWBW Getting Started
 Wayne Warthen (mailto:wwarthen@gmail.com)
-28 Feb 2022
+21 Mar 2022
 
 
 
@@ -17,7 +17,7 @@ RomWBW
 Z80/Z180 System Software
 
 Version 3.1 Pre-release
-28 Feb 2022
+21 Mar 2022
 
 Wayne Warthen wwarthen@gmail.com
 

Source/CBIOS/cbios.asm

@@ -302,6 +302,13 @@ BOOT:
 	; STANDARD BOOT INVOCATION
 	;LD	SP,STACK	; STACK FOR INITIALIZATION
 	LD	SP,CCP_LOC	; PUT STACK JUST BELOW CCP
+;
+#IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nCBIOS Starting...$"
+	CALL	PRTSTRD
+	.DB	"\r\nCopying INIT code to 0x8000...$"
+#ENDIF
 ;
 	; COPY INITIALIZATION CODE TO RUNNING LOCATION $8000
 	LD	HL,BUFPOOL
@@ -311,6 +318,11 @@ BOOT:
 	PUSH	HL		; SAVE START ADR AGAIN FOR BELOW
 	PUSH	BC		; SAVE LENGTH FOR BELOW
 	LDIR			; COPY THE CODE
+;
+#IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nClearing disk buffer...$"
+#ENDIF
 ;
 	; CLEAR BUFFER
 	POP	BC		; RECOVER LENGTH
@@ -320,10 +332,30 @@ BOOT:
 	INC	DE		; OFFSET DEST
 	DEC	BC		; REDUCE LEN BY ONE
 	LDIR			; USE LDIR TO FILL
+;
+#IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nStarting INIT routine at 0x8000$"
+#ENDIF
 ;
 	CALL	INIT		; PERFORM COLD BOOD ROUTINE
+;
+#IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nResetting CP/M...$"
+#ENDIF
 	CALL	RESCPM		; RESET CPM
+;
+#IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nPerforming Auto Submit...$"
+#ENDIF
 	CALL	AUTOSUB		; PREP AUTO SUBMIT, IF APPROPRIATE
+;
+#IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nLaunching CP/M...$"
+#ENDIF
 ;
 	JR	GOCPM		; THEN OFF TO CP/M WE GO...
 ;
@@ -444,6 +476,12 @@ GOCPM:
 CURDSK:
 	LD	A,(CDISK)		; GET CURRENT USER/DISK
 GOCCP:
+;
+#IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nTransfer to CCP...$"
+#ENDIF
+;
 	LD	C,A			; SETUP C WITH CURRENT USER/DISK, ASSUME IT IS OK
 	JP	CCP_LOC			; JUMP TO COMMAND PROCESSOR
 ;
@@ -2011,6 +2049,12 @@ BUFPOOL	.EQU	$		; START OF BUFFER POOL
 HEAPEND	.EQU	CBIOS_END - 64		; TOP OF HEAP MEM, END OF CBIOS LESS 32 ENTRY STACK
 ;
 INIT:
+;
+#IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nStarting INIT....$"
+#ENDIF
+;
 	DI				; NO INTERRUPTS FOR NOW
 
 	; ADJUST BOOT VECTOR TO REBOOT ROUTINE
@@ -2068,12 +2112,21 @@ INIT:
 	LD	(BNKBIOS),A		; ... AND SAVE IT
 	LD	A,E			; GET USER BANK RETURNED IN E
 	LD	(BNKUSER),A		; ... AND SAVE IT
-
+;
+  #IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nReseting HBIOS....$"
+  #ENDIF
+;
 	; SOFT RESET HBIOS
 	LD	B,BF_SYSRESET		; HB FUNC: RESET
 	LD	C,BF_SYSRES_INT		; WARM START
 	RST	08			; DO IT
-
+;
+  #IF DEBUG
+	CALL	PRTSTRD
+	.DB	"\r\nCopying HCB....$"
+  #ENDIF
 	; CREATE A TEMP COPY OF THE HBIOS CONFIG BLOCK (HCB)
 	; FOR REFERENCE USE DURING INIT
 	LD	B,BF_SYSSETCPY		; HBIOS FUNC: SETUP BANK COPY

Source/CBIOS/config.asm

@@ -4,6 +4,7 @@
 CLRRAMDISK	.EQU	CLR_AUTO	; CLR_ALWAYS, CLR_NEVER, CLR_AUTO (CLEAR IF INVALID DIR AREA)
 WRTCACHE	.EQU	TRUE		; ENABLE WRITE CACHING IN CBIOS (DE)BLOCKING ALGORITHM
 DSKTRACE	.EQU	FALSE		; ENABLE TRACING OF CBIOS DISK FUNCTION CALLS
+DEBUG		.EQU	FALSE		; MISCELLANEOUS DEBUG TRACING
 ;
 CPM_LOC		.EQU	$D000		; LOCATION OF START OF CCP
 ;

Source/CBIOS/util.asm

@@ -105,14 +105,61 @@ WRITESTR2:
 	POP	AF
 	RET
 ;
+#IF DEBUG
+;
+; PRINT A STRING AT ADDRESS SPECIFIED IN HL
+; STRING MUST BE TERMINATED BY '$'
+; USAGE:
+;   LD	HL,MYSTR
+;   CALL PRTSTR
+;   ...
+;   MYSTR: .DB  "HELLO$"
+;
+PRTSTR:
+	LD	A,(HL)
+	INC	HL
+	CP	'$'
+	RET	Z
+	CALL	COUT
+	JR	PRTSTR
 ;
+; PRINT A STRING DIRECT: REFERENCED BY POINTER AT TOP OF STACK
+; STRING MUST BE TERMINATED BY '$'
+; USAGE:
+;   CALL PRTSTRD
+;   .DB  "HELLO$"
+;   ...
 ;
-TSTPT:
-	PUSH	DE
-	LD	DE,STR_TSTPT
-	CALL	WRITESTR
-	POP	DE
-	JR	REGDMP			; DUMP REGISTERS AND RETURN
+PRTSTRD:
+	EX	(SP),HL
+	PUSH	AF
+	CALL	PRTSTR
+	POP	AF
+	EX	(SP),HL
+	RET
+;
+; PRINT A STRING INDIRECT: REFERENCED BY INDIRECT POINTER AT TOP OF STACK
+; STRING MUST BE TERMINATED BY '$'
+; USAGE:
+;   CALL PRTSTRI(MYSTRING)
+;   MYSTRING	.DB	"HELLO$"
+;
+PRTSTRI:
+	EX	(SP),HL
+	PUSH	AF
+	LD	A,(HL)
+	INC	HL
+	PUSH	HL
+	LD	H,(HL)
+	LD	L,A
+	CALL	PRTSTR
+	POP	HL
+	INC	HL
+	POP	AF
+	EX	(SP),HL
+	RET
+;
+#ENDIF
 ;
 ; PANIC: TRY TO DUMP MACHINE STATE
 ;

Source/Doc/Architecture.md

@@ -223,6 +223,18 @@ initialization routine. At this point, the prior HBIOS code has been
 discarded and overwritten. Finally, the Boot Loader is invoked just like
 a ROM Boot.
 
+ROM-less Boot
+-------------
+
+Some hardware supported by RomWBW has a special mechanism for loading
+the initial code.  These systems have no ROM chips.  However, they
+have a small hardware bootstrap that loads a chunk of code from a
+disk device directlly into RAM at system startup.
+
+The startup then proceeds very much like the Application Boot
+process described above.  HBIOS is installed in it's operating bank
+and control is passed to the loader.
+
 Notes
 -----
 

Source/HBIOS/hbios.asm

@@ -1530,21 +1530,51 @@ MBC_SINGLE:
 ;
 #ENDIF
 ;
-; IF THIS IS A ROM-LESS SYSTEM, THEN WE NEED TO COPY THE "APP" BANK TO
-; TPA.  IT IS DONE PRIOR TO COPYING HBIOS TO IT'S FINAL BANK BECAUSE
-; THE SOURCE OF THE APP BANK CODE MAY BE THE BANK THAT HBIOS WANTS TO
-; USE AS IT'S FINAL LOCATION (PRIMARILY IN CASE OF RAMBOOT WHERE THE
-; SYSTEM HAS THE MINIMUM 128KB OF RAM).
+; IF THIS IS A ROM-LESS SYSTEM, THEN WE NEED TO COPY THE PAYLOAD
+; (LOADER, MONITOR, ZSDOS) THAT HAS BEEN LOADED TO PHYSICAL RAM
+; BANKS 0 AND 1 TO THE USER TPA BANK TO RUN AFTER BOOT.
+; IT IS DONE PRIOR TO COPYING HBIOS TO IT'S FINAL BANK BECAUSE
+; THE PAYLOAD MAY EXTEND INTO THE HBIOS OPERATING BANK.  THIS
+; HAPPENS PRIMARILY IN THE CASE WHERE THE
+; SYSTEM HAS THE MINIMUM 128KB OF RAM.
 ;
 #IFDEF ROMBOOT
   #IF (ROMSIZE == 0)
-	LD	A,(HB_CURBNK)
+ ; 
+	; THE PAYLOAD IS LIKELY TO CROSS OVER THE RAM BANK 0/1
+	; BOUNDARY.  BNKCPY DOES NOT HANDLE THIS BECAUSE IT ASSUMES
+	; THE COMMON BANK IS USED AFTER PASSING OVER THE BANK
+	; BOUNDARY.  WE WORK AROUND THAT HERE BY DOING TWO COPIES.
+	; THE FIRST ONE HANDLES THE PORTION OF THE PAYLOAD FROM THE
+	; END OF HBIOS TO THE BANK BOUNDARY ($8000).  THE SECOND
+	; ONE HANDLES THE PORTION THAT EXTENDS INTO THE SECOND
+	; PHYSICAL RAM BANK.
+;
+	; COPY PORTION OF PAYLOAD FOLLOWING HBIOS TO THE BANK
+	; BOUNDARY AT $8000 INTO START OF TPA.
+	LD	A,BID_RAM0
 	LD	(HB_SRCBNK),A
 	LD	A,BID_USR
 	LD	(HB_DSTBNK),A
 	LD	HL,HB_END
 	LD	DE,0
-	LD	BC,$8000
+	LD	BC,$8000-HB_END
+;
+    #IF (MEMMGR == MM_Z280)
+	CALL	Z280_BNKCPY
+    #ELSE
+	CALL	HBX_BNKCPY
+    #ENDIF
+;
+	; COPY REMAINDER OF PAYLOAD EXTENDING INTO THE SECOND PHYSICAL
+	; RAM BANK.  NOTE THAT THE DESTINATION ADDRESS (DE) IS
+	; ALREADY CORRECT FROM THE PRIOR COPY.
+	LD	A,BID_RAM0+1
+	LD	(HB_SRCBNK),A
+	LD	HL,$0000
+	; DE IS ALREADY CORRECT
+	LD	BC,$8000-($8000-HB_END)
+;
     #IF (MEMMGR == MM_Z280)
 	CALL	Z280_BNKCPY
     #ELSE
@@ -3697,6 +3727,11 @@ SYS_RESINT:
 ; GO BACK TO ROM BOOT LOADER
 ;
 SYS_RESWARM:
+;
+#IF (ROMSIZE == 0)
+	JR	SYS_RESCOLD
+#ENDIF
+;
 	CALL	SYS_RESINT
 ;
 #IF (MEMMGR == MM_Z280)
@@ -3713,6 +3748,14 @@ SYS_RESWARM:
 ; RESTART SYSTEM AS THOUGH POWER HAD JUST BEEN TURNED ON
 ;
 SYS_RESCOLD:
+;
+#IF (ROMSIZE == 0)
+	LD	DE,STR_RESTART
+	CALL	Z,WRITESTR
+	DI
+	HALT
+#ENDIF
+;
 #IF (MEMMGR == MM_Z280)
 	JP	Z280_RESTART
 #ELSE
@@ -7015,6 +7058,7 @@ STR_LOWBAT	.DB	"\r\n\r\n+++ LOW BATTERY +++$"
 STR_PANIC	.TEXT	"\r\n>>> PANIC: $"
 STR_SYSCHK	.TEXT	"\r\n>>> SYSCHK: $"
 STR_CONTINUE	.TEXT	"\r\nContinue (Y/N)? $"
+STR_RESTART	.TEXT	"\r\n\r\n>>> Press hardware reset button to restart system\r\n\r\n$"
 ;
 #IF (DSKYENABLE)	;	'H','B','I','O',' ',' ',' ',' '
   #IF (DSKYMODE == DSKYMODE_V1)

Source/ver.inc

@@ -2,4 +2,4 @@
 #DEFINE	RMN	1
 #DEFINE	RUP	1
 #DEFINE	RTP	0
-#DEFINE BIOSVER	"3.1.1-pre.161"
+#DEFINE BIOSVER	"3.1.1-pre.162"

Source/ver.lib

@@ -3,5 +3,5 @@ rmn	equ	1
 rup	equ	1
 rtp	equ	0
 biosver	macro
-	db	"3.1.1-pre.161"
+	db	"3.1.1-pre.162"
 	endm