Boot and Bank Layout Cleanup

Revised hbios.asm to compile in 3 modes (ROM/APP/IMG boot).  Updated and
simplified ROM bank assignments.

Source/HBIOS/Build.ps1

@@ -58,9 +58,9 @@ if ($Platform -eq "UNA") {$CBiosFile = '../CBIOS/cbios_una.bin'} else {$CBiosFil
 # $TimeStamp = '"' + (Get-Date -Format 'dd-MMM-yyyy') + '"'
 $TimeStamp = '"' + (Get-Date -Format 'yyyy-MM-dd') + '"'
 
-Function Asm($Component, $Opt, $Architecture=$CPUType, $Output="${Component}.bin")
+Function Asm($Component, $Opt, $Architecture=$CPUType, $Output="${Component}.bin", $List="${Component}.lst")
 {
-  $Cmd = "tasm -t${Architecture} -g3 ${Opt} ${Component}.asm ${Output}"
+  $Cmd = "tasm -t${Architecture} -g3 ${Opt} ${Component}.asm ${Output} ${List}"
   $Cmd | write-host
   Invoke-Expression $Cmd | write-host
   if ($LASTEXITCODE -gt 0) {throw "TASM returned exit code $LASTEXITCODE"}
@@ -101,11 +101,9 @@ Asm 'prefix'
 Asm 'romldr'
 if ($Platform -ne "UNA")
 {
-	Asm 'hbios'
+	Asm 'hbios' '-dROMBOOT' -Output 'hbios_rom.bin' -List 'hbios_rom.lst'
-	Asm 'hbfill'
+	Asm 'hbios' '-dAPPBOOT' -Output 'hbios_app.bin' -List 'hbios_rom.lst'
-	Asm 'setup'
+	Asm 'hbios' '-dIMGBOOT' -Output 'hbios_img.bin' -List 'hbios_rom.lst'
-	Asm 'comldr'
-	Asm 'imgldr'
 }
 
 # Generate result files using components above
@@ -139,9 +137,9 @@ if ($Platform -eq "UNA")
 }
 else 
 {
-	Concat 'setup.bin','hbios.bin','hbfill.bin','osimg.bin','osimg.bin',$RomDiskFile $RomFile
+	Concat 'hbios_rom.bin','osimg.bin','osimg.bin','osimg.bin',$RomDiskFile $RomFile
-	Concat 'comldr.bin','hbios.bin','osimg.bin' $ComFile
+	Concat 'hbios_app.bin','osimg.bin' $ComFile
-	Concat 'imgldr.bin','hbios.bin','osimg.bin' $ImgFile
+	Concat 'hbios_img.bin','osimg.bin' $ImgFile
 }
 
 # Cleanup

Source/HBIOS/Layout.txt

@@ -3,20 +3,18 @@ Final Output Files
 ------------------
 
 ROM Output File [512K] -> <config>.rom
-  setup [32K]			romboot?
+  hbios_rom [32K]
-  hbios+hbfill [32K]
   OSIMG [32K]
   OSIMG [32K] (used as filler)
+  OSIMG [32K] (used as filler)
   romdisk - [384K]
 
 COM Output File -> <config>.com
-  comldr [varies]		appboot?
+  hbios_com [varies]
-  hbios [varies]
   OSIMG [32K]
 
 IMG Output File -> <config>.img
-  imgldr [varies]		imgboot?
+  hbios_img [varies]
-  hbios [varies]
   OSIMG [32K]
 
 -------------------------
@@ -43,43 +41,7 @@ ZSYS [12K] -> zsys.bin
 Compilation Units
 -----------------
 
-setup.asm -> setup.bin:		romboot?
+hbios.asm -> hbios_rom.bin, hbios_app.bin, hbios_img.bin
-  std.asm
-    ver.inc
-    hbios.inc
-    build.inc
-      <config>.asm
-    plt_<platform>.inc
-  hbios.exp
-  loader			boot?
-    xio
-    memmgr
-
-comldr.asm -> comldr.bin:	appboot?
-  std.asm
-    ver.inc
-    hbios.inc
-    build.inc
-      <config>.asm
-    plt_<platform>.inc
-  hbios.exp
-  loader			boot?
-    xio
-    memmgr
-
-imgldr.asm -> imgldr.bin:	imgboot?
-  std.asm
-    ver.inc
-    hbios.inc
-    build.inc
-      <config>.asm
-    plt_<platform>.inc
-  hbios.exp
-  loader			boot?
-    xio
-    memmgr
-
-hbios.bin:
   std.asm
     ver.inc
     hbios.inc
@@ -112,3 +74,30 @@ dbgmon.asm -> dbgmon.bin:
   util.asm
   memmgr.asm
   dsky.asm
+  
+=======================================================================
+HBIOS Loading Modes:
+  ROMBOOT: Startup from ROM Bank BID_BOOT
+  APPBOOT: Startup as CP/M application
+  IMGBOOT: Startup from RAM Bank BID_USR
+=======================================================================
+
+ - If not (APPBOOT), include page 0
+
+ - Base Hardware Init
+   - Iff (ROMBOOT), init BBR
+
+ - Install Proxy
+   - Set CURBNK:
+     - If ROMBOOT, then BID_BOOT, else BID_USR
+
+ - Install HBIOS
+   - Copy from CURBNK:0 --> BID_BIOS:0 ($8000 bytes)
+
+ - Transition to HBIOS in BID_BIOS
+
+ - Copy OS Image to USR Bank
+   - If (ROM_MODE), copy BID_OS:0 --> BID_USR:0
+   - Else, copy BID_USR:<os image start> --> BID_USR:0
+
+ - Chain to BID_USR:0

Source/HBIOS/dbgmon.asm

@@ -39,8 +39,6 @@ BS:		 .EQU	08H		; ASCII BACKSPACE CHARACTER
 ;
 #INCLUDE "util.asm"
 ;
-#INCLUDE "memmgr.asm"
-;
 #IF DSKYENABLE
 ;
 #INCLUDE "dsky.asm"
@@ -613,28 +611,16 @@ SERIALCMDLOOP:
 ;_____________________________________________________________________________
 ;
 BOOT:
-	; ENSURE DEFAULT MEMORY PAGE CONFIGURATION
-;#IF (PLATFORM == PLT_N8)
-;	LD	A,DEFACR
-;	OUT0	(ACR),A
-;	XOR	A
-;	OUT0	(RMAP),A
-;#ELSE
-;	XOR	A
-;	OUT	(MPCL_ROM),A
-;	OUT	(MPCL_RAM),A
-;#ENDIF
 #IF (PLATFORM == PLT_UNA)
 	LD	BC,$01FB		; UNA FUNC = SET BANK
 	LD	DE,$0000		; ROM BANK 0
 	CALL	$FFFD			; DO IT (RST 08 NOT SAFE HERE)
+	JP	0000H			; JUMP TO RESTART ADDRESS
 #ELSE
-	LD	A,BID_BOOT
+	LD	A,BID_BOOT		; BOOT BANK
-	CALL	BNKSEL
+	LD	HL,0			; ADDRESS ZERO
+	CALL	HB_BNKCALL		; DOES NOT RETURN
 #ENDIF
-	; JUMP TO RESTART ADDRESS
-	JP	0000H
-
 
 ;__KLOP_______________________________________________________________________
 ;

Source/HBIOS/hbios.asm

@@ -6,6 +6,8 @@
 ; INCLUDE GENERIC STUFF
 ;
 #INCLUDE "std.asm"
+;
+#IFNDEF	APPBOOT
 ;
 	.ORG	0
 ;
@@ -50,7 +52,56 @@ DESC	.DB	"ROMWBW v", BIOSVER, ", Copyright 2015, Wayne Warthen, GNU GPL v3", 0
 ;
 	.FILL	($100 - $),$FF		; PAD REMAINDER OF PAGE ZERO
 ;
-HCB	.FILL	$100,$FF		; RESERVED FOR HBIOS CONTROL BLOCK
+#ENDIF
+;
+;==================================================================================================
+;   HBIOS CONFIGURATION BLOCK (HCB)
+;==================================================================================================
+;
+		.ORG	HCB_LOC
+HCB:
+		JP	HB_START
+;
+		.DB	'W',~'W'	; MARKER
+		.DB	RMJ << 4 | RMN	; FIRST BYTE OF VERSION INFO
+		.DB	RUP << 4 | RTP	; SECOND BYTE OF VERSION INFO
+;
+CB_PLT		.DB	PLATFORM
+CB_CPUMHZ	.DB	CPUMHZ
+CB_CPUKHZ	.DW	CPUKHZ
+CB_RAMBANKS	.DB	RAMSIZE / 32
+CB_ROMBANKS	.DB	ROMSIZE / 32
+;
+CB_BOOTVOL	.DW	0		; BOOT VOLUME IS UNIT/SLICE, SET BY LOADER
+CB_BOOTBID	.DB	0		; BOOT BANK ID, SET BY LOADER
+CB_SERDEV	.DB	0		; PRIMARY SERIAL UNIT IS UNIT #0 BY FIAT
+CB_CRTDEV	.DB	$FF		; PRIMARY CRT UNIT, $FF UNTIL AFTER HBIOS INIT
+CB_CONDEV	.DB	$FF		; CONSOLE UNIT, $FF UNTIL AFTER HBIOS INIT
+;
+;CB_CUREMU	.DB	VDAEMU		; CURRENT VDA TERMINAL EMULATION (DEPRECATED)
+;CB_CURVDA	.DB	VDADEV		; CURRENT VDA TARGET FOR EMULATION (DEPRECATED)
+;
+; MEMORY MANAGEMENT VARIABLES START AT $20
+;
+		.FILL	(HCB + $20 - $),0
+;
+CB_HEAP		.DW	0
+CB_HEAPTOP	.DW	0
+;
+; STANDARD BANK ID'S START AT $D8
+;
+		.FILL	(HCB + $D8 - $),0
+;
+CB_BIDCOM	.DB	BID_COM
+CB_BIDUSR	.DB	BID_USR
+CB_BIDBIOS	.DB	BID_BIOS
+CB_BIDAUX	.DB	BID_AUX
+CB_BIDRAMD0	.DB	BID_RAMD0
+CB_BIDRAMDN	.DB	BID_RAMDN
+CB_BIDROMD0	.DB	BID_ROMD0
+CB_BIDROMDN	.DB	BID_ROMDN
+;
+	.FILL	(HCB + HCB_SIZ - $),0	; PAD REMAINDER OF HCB
 ;
 ;==================================================================================================
 ;   HBIOS UPPER MEMORY PROXY (RELOCATED TO RUN IN TOP 2 PAGES OF CPU RAM)
@@ -423,7 +474,11 @@ HBX_STACK	.EQU	$
 ;
 ; HBIOS PROXY MGMT BLOCK (TOP 32 BYTES)
 ;
+#IFDEF ROMBOOT
 	.DB	BID_BOOT	; CURRENTLY ACTIVE LOW MEMORY BANK ID
+#ELSE
+	.DB	BID_USR		; CURRENTLY ACTIVE LOW MEMORY BANK ID
+#ENDIF
 	.DB	$FF		; DEPRECATED!!!
 	.DW	0		; BNKCPY SOURCE ADDRESS
 	.DB	BID_USR		; BNKCPY SOURCE BANK ID
@@ -468,10 +523,25 @@ HB_START:
 	XOR	A
 	OUT0	(Z180_RCR),A
 
+	; SET DEFAULT CPU CLOCK MULTIPLIERS (XTAL / 2)
+	XOR	A
+	OUT0	(Z180_CCR),A
+	OUT0	(Z180_CMR),A
+
 	; SET DEFAULT WAIT STATES TO ACCURATELY MEASURE CPU SPEED
 	LD	A,$F0
 	OUT0	(Z180_DCNTL),A
 
+ 	; MMU SETUP
+ 	LD	A,$80	
+ 	OUT0	(Z180_CBAR),A		; SETUP FOR 32K/32K BANK CONFIG	
+ #IFDEF ROMBOOT	
+ 	XOR	A	
+ 	OUT0	(Z180_BBR),A		; BANK BASE = 0	
+ #ENDIF	
+ 	LD	A,(RAMSIZE + RAMBIAS - 64) >> 2	
+ 	OUT0	(Z180_CBR),A		; COMMON BASE = LAST (TOP) BANK	
+
 #IF (Z180_CLKDIV >= 1)
 	; SET CLOCK DIVIDE TO 1 RESULTING IN FULL XTAL SPEED
 	LD	A,$80
@@ -485,6 +555,52 @@ HB_START:
 #ENDIF
 
 #ENDIF
+;
+#IF (PLATFORM == PLT_ZETA2)
+	; SET PAGING REGISTERS
+#IFDEF ROMBOOT
+	XOR	A
+	OUT	(MPGSEL_0),A
+	INC	A
+	OUT	(MPGSEL_1),A
+#ENDIF
+	LD	A,62
+	OUT	(MPGSEL_2),A
+	INC	A
+	OUT	(MPGSEL_3),A
+	; ENABLE PAGING
+	LD	A,1
+	OUT	(MPGENA),A
+#ENDIF
+;
+; INSTALL PROXY IN UPPER MEMORY
+;
+	LD	HL,HBX_IMG
+	LD	DE,HBX_LOC
+	LD	BC,HBX_SIZ
+	LDIR
+;
+; INSTALL HBIOS TO RAM BANK
+;
+	LD	A,(HB_CURBNK)
+	LD	(HB_SRCBNK),A
+	LD	A,BID_BIOS
+	LD	(HB_DSTBNK),A
+	LD	HL,0
+	LD	DE,0
+	LD	BC,$8000
+	CALL	HB_BNKCPY
+;
+; TRANSITION TO HBIOS IN RAM BANK
+;
+	LD	A,BID_BIOS	; BIOS BANK ID
+	LD	HL,HB_START1	; EXECUTION RESUMES HERE
+	CALL	HBX_BNKCALL	; CONTINUE IN RAM BANK, DO NOT RETURN
+	HALT			; WE SHOULD NOT COME BACK HERE!
+HB_START1:			; BNKCALL ARRIVES HERE, BUT NOW RUNNING IN RAM BANK
+	LD	SP,HBX_LOC	; RESET STACK SINCE WE DO NOT RETURN
+;
+;
 ;
 	CALL	HB_CPUSPD		; CPU SPEED DETECTION
 ;
@@ -578,21 +694,6 @@ INITSYS1:
 ;
 	LD	HL,(HCB + HCB_HEAPTOP)
 	LD	(HEAPCURB),HL
-;;
-;; RUN THROUGH ALL SERIAL DEVICES AND PERFORM FULL INITIALIZATION
-;;
-;	LD	A,(CIO_CNT)		; GET SERIAL DEVICE COUNT
-;	LD	B,A			; INIT LOOP COUNTER
-;	LD	C,0			; INIT UNIT INDEX
-;INITSYS2:	
-;	PUSH	BC			; SAVE LOOP CONTROL
-;	LD	B,BF_CIOINIT		; FUNC: INIT
-;	LD	DE,-1			; INIT W/ CURRENT CONFIG
-;	CALL	CIO_DISPATCH		; CALL SERIAL UNIT DISPATCHER
-;	;CALL	NZ,?????		; IF ERROR, SHOW IT
-;	POP	BC			; RESTORE LOOP CONTROL
-;	INC	C			; NEXT UNIT
-;	DJNZ	INITSYS2		; LOOP TILL ALL UNITS DONE
 ;
 ; NOW SWITCH TO CRT CONSOLE IF CONFIGURED
 ;
@@ -623,6 +724,42 @@ INITSYS1:
 INITSYS3:
 ;
 	CALL	PRTSUM			; PRINT UNIT/DEVICE SUMMARY TABLE
+;
+; CHAIN TO OS LOADER
+;
+#IFDEF ROMBOOT
+	; PERFORM BANK CALL TO OS IMAGES BANK
+	LD	A,BID_OSIMG	; CHAIN TO OS IMAGES BANK
+	LD	HL,0		; ENTER AT ADDRESS 0
+	CALL	HB_BNKCALL	; GO THERE
+	HALT			; WE SHOULD NEVER COME BACK!
+#ELSE
+	; COPY OS IMAGE: BID_USR:<IMG START> --> BID_USR:0
+	LD	A,BID_USR
+	LD	(HB_SRCBNK),A
+	LD	(HB_DSTBNK),A
+	LD	HL,HB_END
+	LD	DE,0
+	LD	BC,$8000
+	CALL	HB_BNKCPY
+;
+	; PERFORM BANK CALL TO OS IMAGES BANK
+	LD	A,BID_USR	; CHAIN TO OS IMAGES BANK
+	LD	HL,0		; ENTER AT ADDRESS 0
+	CALL	HB_BNKCALL	; GO THERE
+	HALT			; WE SHOULD NEVER COME BACK!
+
+
+;	; SLIDE OS IMAGES BLOB DOWN TO $0000
+;	LD	HL,LDR_END	; SOURCE IS LOADER END
+;	LD	BC,HB_END	; PLUS HBIOS IMAGE SIZE
+;	ADD	HL,BC		; FINAL SOURCE ADDRESS
+;	LD	DE,0		; TARGET ADDRESS IS ZERO
+;	LD	BC,BNKTOP	; MAX SIZE OF OS IMAGES
+;	LDIR			; DO IT
+;	; JUMP TO START
+;	JP	0		; AND CHAIN
+#ENDIF
 ;
 	RET
 ;
@@ -1792,7 +1929,7 @@ SIZ_TERM	.EQU	$ - ORG_TERM
 #INCLUDE "time.asm"
 #INCLUDE "bcd.asm"
 #INCLUDE "decode.asm"
-#INCLUDE "xio.asm"
+;#INCLUDE "xio.asm"
 ;
 #IF (DSKYENABLE)
 #DEFINE	DSKY_KBD
@@ -2537,9 +2674,9 @@ COUT:
 	JR	COUT2			; CONTINUE
 ;
 COUT1:
-	; USE XIO
+	;; USE XIO
-	LD	A,E			; GET OUTPUT CHAR BACK TO ACCUM
+	;LD	A,E			; GET OUTPUT CHAR BACK TO ACCUM
-	CALL	XIO_OUTC		; OUTPUT VIA XIO
+	;CALL	XIO_OUTC		; OUTPUT VIA XIO
 ;
 COUT2:
 	; RESTORE ALL REGISTERS
@@ -2569,8 +2706,8 @@ CIN:
 	JR	CIN2			; CONTINUE
 ;
 CIN1:
-	; USE XIO
+	;; USE XIO
-	CALL	XIO_INC			; GET CHAR
+	;CALL	XIO_INC			; GET CHAR
 ;
 CIN2:
 ;
@@ -2599,8 +2736,8 @@ CST:
 	JR	CST2			; CONTINUE
 ;
 CST1:
-	; USE XIO
+	;; USE XIO
-	CALL	XIO_IST			; GET STATUS
+	;CALL	XIO_IST			; GET STATUS
 ;
 CST2:
 	; RESTORE REGISTERS (AF IS OUTPUT)
@@ -2653,11 +2790,16 @@ HB_BCDTMP	.FILL	5,0		; TEMPORARY BCD NUMBER STORAGE
 ;
 HB_WRKBUF	.FILL	512,0		; INTERNAL DISK BUFFER
 ;
-HB_END		.EXPORT	HB_END		; EXPORT ENDING ADDRESS
+;HB_END		.EXPORT	HB_END		; EXPORT ENDING ADDRESS
+HB_END		.EQU	$
 ;
 SLACK		.EQU	BNKTOP - $
 		.ECHO	"HBIOS space remaining: "
 		.ECHO	SLACK
 		.ECHO	" bytes.\n"
+;
+#IFDEF ROMBOOT
+		.FILL	SLACK
+#ENDIF
 ;
 		.END

Source/HBIOS/hbios.inc

@@ -118,17 +118,20 @@ EMUTYP_ANSI	.EQU	2		; ANSI
 HCB_LOC		.EQU	$100		; LOCATION OF HCB IN HBIOS BANK
 HCB_SIZ		.EQU	$100		; SIZE OF HCB DATA BLOCK
 ;
-HCB_CPUMHZ	.EQU	$05		; CPU SPEED IN MHZ (BYTE)
+HCB_MARKER	.EQU	$03		; MARKER ('W',~'W') (WORD)
-HCB_CPUKHZ	.EQU	$06		; CPU SPEED IN KHZ (WORD)
+HCB_VERSION	.EQU	$05		; HBIOS VERSION NUM
-HCB_RAMBANKS	.EQU	$08		; TOTAL SIZE OF RAM IN 32K BANKS (BYTE)
+HCB_PLATFORM	.EQU	$07		; PLATFORM ID
-HCB_ROMBANKS	.EQU	$09		; TOTAL SIZE OF ROM IN 32K BANKS (BYTE)
+HCB_CPUMHZ	.EQU	$08		; CPU SPEED IN MHZ (BYTE)
-HCB_BOOTVOL	.EQU	$0A		; BOOT VOLUME, MSB=DEV/UNIT, LSB=LU (WORD)
+HCB_CPUKHZ	.EQU	$09		; CPU SPEED IN KHZ (WORD)
-HCB_BOOTBID	.EQU	$0C		; BANK ID OF ROM PAGE BOOTED (BYTE)
+HCB_RAMBANKS	.EQU	$0B		; TOTAL SIZE OF RAM IN 32K BANKS (BYTE)
-HCB_SERDEV	.EQU	$0D		; PRIMARY SERIAL DEVICE/UNIT (BYTE)
+HCB_ROMBANKS	.EQU	$0C		; TOTAL SIZE OF ROM IN 32K BANKS (BYTE)
-HCB_CRTDEV	.EQU	$0E		; CRT DISPLAY DEVICE/UNIT (BYTE)
+HCB_BOOTVOL	.EQU	$0D		; BOOT VOLUME, MSB=DEV/UNIT, LSB=LU (WORD)
-HCB_CONDEV	.EQU	$0F		; ACTIVE CONSOLE DEVICE/UNIT (BYTE)
+HCB_BOOTBID	.EQU	$0F		; BANK ID OF ROM PAGE BOOTED (BYTE)
-;HCB_CUREMU	.EQU	$10		; CURRENT VDA TERMINAL EMULATION (DEPRECATED)
+HCB_SERDEV	.EQU	$10		; PRIMARY SERIAL DEVICE/UNIT (BYTE)
-;HCB_CURVDA	.EQU	$11		; CURRENT VDA TARGET FOR EMULATION (DEPRECATED)
+HCB_CRTDEV	.EQU	$11		; CRT DISPLAY DEVICE/UNIT (BYTE)
+HCB_CONDEV	.EQU	$12		; ACTIVE CONSOLE DEVICE/UNIT (BYTE)
+;HCB_CUREMU	.EQU	$13		; CURRENT VDA TERMINAL EMULATION (DEPRECATED)
+;HCB_CURVDA	.EQU	$14		; CURRENT VDA TARGET FOR EMULATION (DEPRECATED)
 ;
 HCB_HEAP	.EQU	$20		; DWORD ADDRESS OF START OF HEAP
 HCB_HEAPTOP	.EQU	$22		; DWORD ADDRESS OF TOP OF HEAP

Source/HBIOS/loader.asm

@@ -1,270 +0,0 @@
-;
-;==================================================================================================
-;   LOADER
-;==================================================================================================
-;
-P2LOC		.EQU	$F000	; PHASE 2 RUN LOCATION
-;
-#IFDEF ROMLOAD
-CURBNK		.EQU	BID_BOOT
-#ELSE
-CURBNK		.EQU	BID_USR
-#ENDIF
-;
-;==================================================================================================
-;   HBIOS CONFIGURATION BLOCK (HCB)
-;==================================================================================================
-;
-		.ORG	$ + P2LOC
-CB:
-		.DB	'W',~'W'	; MARKER
-		.DB	RMJ << 4 | RMN	; FIRST BYTE OF VERSION INFO
-		.DB	RUP << 4 | RTP	; SECOND BYTE OF VERSION INFO
-;
-CB_PLT		.DB	PLATFORM
-CB_CPUMHZ	.DB	CPUMHZ
-CB_CPUKHZ	.DW	CPUKHZ
-CB_RAMBANKS	.DB	RAMSIZE / 32
-CB_ROMBANKS	.DB	ROMSIZE / 32
-;
-CB_BOOTVOL	.DW	0		; BOOT VOLUME IS UNIT/SLICE, SET BY LOADER
-CB_BOOTBID	.DB	0		; BOOT BANK ID, SET BY LOADER
-CB_SERDEV	.DB	0		; PRIMARY SERIAL UNIT IS UNIT #0 BY FIAT
-CB_CRTDEV	.DB	$FF		; PRIMARY CRT UNIT, $FF UNTIL AFTER HBIOS INIT
-CB_CONDEV	.DB	$FF		; CONSOLE UNIT, $FF UNTIL AFTER HBIOS INIT
-;
-;CB_CUREMU	.DB	VDAEMU		; CURRENT VDA TERMINAL EMULATION (DEPRECATED)
-;CB_CURVDA	.DB	VDADEV		; CURRENT VDA TARGET FOR EMULATION (DEPRECATED)
-;
-; MEMORY MANAGEMENT VARIABLES START AT $20
-;
-		.FILL	(CB + $20 - $),0
-;
-CB_HEAP		.DW	0
-CB_HEAPTOP	.DW	0
-;
-; STANDARD BANK ID'S START AT $D8
-;
-		.FILL	(CB + $D8 - $),0
-;
-CB_BIDCOM	.DB	BID_COM
-CB_BIDUSR	.DB	BID_USR
-CB_BIDBIOS	.DB	BID_BIOS
-CB_BIDAUX	.DB	BID_AUX
-CB_BIDRAMD0	.DB	BID_RAMD0
-CB_BIDRAMDN	.DB	BID_RAMDN
-CB_BIDROMD0	.DB	BID_ROMD0
-CB_BIDROMDN	.DB	BID_ROMDN
-;
-	.FILL	(CB + HCB_SIZ - $),0	; PAD REMAINDER OF HCB
-;
-	.ORG	$ - P2LOC
-;
-;==================================================================================================
-;   COLD START
-;==================================================================================================
-;
-START:
-	DI			; NO INTERRUPTS
-	IM	1		; INTERRUPT MODE 1
-	LD	SP,HBX_LOC	; SETUP INITIAL STACK JUST BELOW HBIOS PROXY
-;
-; HARDWARE BOOTSTRAP FOR Z180
-; FOR N8, ACR & RMAP ARE ASSUMED TO BE ALREADY SET OR THIS CODE
-; WOULD NOT BE EXECUTING
-;
-#IF ((PLATFORM == PLT_N8) | (PLATFORM == PLT_MK4))
-	; SET BASE FOR CPU IO REGISTERS
-   	LD	A,Z180_BASE
-	OUT0	(Z180_ICR),A
-
-	; DISABLE REFRESH
-	XOR	A
-	OUT0	(Z180_RCR),A
-
-	; SET DEFAULT CPU CLOCK MULTIPLIERS (XTAL / 2)
-	XOR	A
-	OUT0	(Z180_CCR),A
-	OUT0	(Z180_CMR),A
-
-	; SET DEFAULT WAIT STATES
-	LD	A,$F0
-	OUT0	(Z180_DCNTL),A
-
-	; MMU SETUP
-	LD	A,$80
-	OUT0	(Z180_CBAR),A		; SETUP FOR 32K/32K BANK CONFIG
-#IFDEF ROMLOAD
-	XOR	A
-	OUT0	(Z180_BBR),A		; BANK BASE = 0
-#ENDIF
-	LD	A,(RAMSIZE + RAMBIAS - 64) >> 2
-	OUT0	(Z180_CBR),A		; COMMON BASE = LAST (TOP) BANK
-
-#IF (Z180_CLKDIV >= 1)
-	; SET CLOCK DIVIDE TO 1 RESULTING IN FULL XTAL SPEED
-	LD	A,$80
-	OUT0	(Z180_CCR),A
-#ENDIF
-
-#IF (Z180_CLKDIV >= 2)
-	; SET CPU MULTIPLIER TO 1 RESULTING IN XTAL * 2 SPEED
-	LD	A,$80
-	OUT0	(Z180_CMR),A
-#ENDIF
-
-	; SET DESIRED WAIT STATES
-	LD	A,0 + (Z180_MEMWAIT << 6) | (Z180_IOWAIT << 4)
-	OUT0	(Z180_DCNTL),A
-#ENDIF
-;
-; HARDWARE BOOTSTRAP FOR ZETA 2
-;
-#IF (PLATFORM == PLT_ZETA2)
-	; SET PAGING REGISTERS
-#IFDEF ROMLOAD
-	XOR	A
-	OUT	(MPGSEL_0),A
-	INC	A
-	OUT	(MPGSEL_1),A
-#ENDIF
-	LD	A,62
-	OUT	(MPGSEL_2),A
-	INC	A
-	OUT	(MPGSEL_3),A
-	; ENABLE PAGING
-	LD	A,1
-	OUT	(MPGENA),A
-#ENDIF
-;
-; EMIT FIRST SIGN OF LIFE TO SERIAL PORT
-;
-	CALL	XIO_INIT	; INIT SERIAL PORT
-#IFNDEF ROMLOAD
-	CALL	XIO_CRLF	; FORMATTING
-#ENDIF
-	LD	HL,STR_BOOT	; POINT TO MESSAGE
-	CALL	XIO_OUTS	; SAY HELLO
-;
-; COPY OURSELVES AND LOADER TO HI RAM FOR PHASE 2
-;
-	LD	HL,0		; COPY FROM START OF ROM IMAGE
-	LD	DE,P2LOC	; TO HIMEM RUN LOCATION
-	LD	BC,LDR_END	; COPY FULL IMAGE
-	LDIR
-;
-	CALL	XIO_DOT		; MARK PROGRESS
-;
-	JP	PHASE2		; JUMP TO PHASE 2 BOOT IN UPPER MEMORY
-;
-STR_BOOT	.DB	"RomWBW$"
-;
-; IMBED DIRECT SERIAL I/O ROUTINES
-;
-#INCLUDE "xio.asm"
-#INCLUDE "decode.asm"
-;
-;______________________________________________________________________________________________________________________
-;
-; THIS IS THE PHASE 2 CODE THAT MUST EXECUTE IN UPPER MEMORY
-;
-	.ORG	$ + P2LOC	; WE ARE NOW EXECUTING IN UPPER MEMORY
-;
-PHASE2:
-	CALL	XIO_DOT		; MARK PROGRESS
-;
-; INSTALL HBIOS PROXY IN UPPER MEMORY
-;
-#IFDEF ROMLOAD
-	LD	A,BID_BIOSIMG	; HBIOS IMAGE ROM BANK
-	CALL	BNKSEL		; SELECT IT
-#ENDIF
-	LD	HL,HBX_IMG	; HL := SOURCE OF HBIOS PROXY IMAGE
-#IFNDEF ROMLOAD
-	LD	BC,LDR_END	; SIZE OF LOADER
-	ADD	HL,BC		; OFFSET SOURCE ADDRESS
-#ENDIF
-	LD	DE,HBX_LOC	; DE := DESTINATION TO INSTALL IT
-	LD	BC,HBX_SIZ	; SIZE
-	LDIR			; DO THE COPY
-	LD	A,CURBNK	; BOOT/SETUP BANK
-	LD	(HB_CURBNK),A	; INIT CURRENT BANK
-#IFDEF ROMLOAD
-	CALL	BNKSEL		; SELECT IT
-#ENDIF
-	CALL	XIO_DOT		; MARK PROGRESS
-;
-; INSTALL HBIOS CODE BANK
-;
-#IFDEF ROMLOAD
-	LD	A,BID_BIOSIMG	; SOURCE BANK
-#ELSE
-	LD	A,(HB_CURBNK)	; SOURCE BANK
-#ENDIF
-	LD	(HB_SRCBNK),A	; SET IT
-	LD	A,BID_BIOS	; DESTINATION BANK
-	LD	(HB_DSTBNK),A	; SET IT
-	LD	HL,0		; SOURCE ADDRESS IS ZERO
-#IFNDEF ROMLOAD
-	LD	BC,LDR_END	; SIZE OF LOADER
-	ADD	HL,BC		; OFFSET SOURCE ADDRESS
-#ENDIF
-	LD	DE,0		; TARGET ADDRESS IS ZERO
-	LD	BC,HB_END	; COPY ALL OF HBIOS IMAGE
-	CALL	XIO_DOT		; MARK PROGRESS
-	CALL	HB_BNKCPY	; DO IT
-	CALL	XIO_DOT		; MARK PROGRESS
-;
-; INSTALL HCB INTO HBIOS CODE BANK
-;
-	LD	A,BID_BIOS	; GET BIOS BANK
-	LD	(HB_SRCBNK),A	; SET AS SOURCE (IRRELEVANT)
-	LD	(HB_DSTBNK),A	; SET AS DEST
-	LD	HL,CB		; LOCAL LOADER HCB ADDRESS
-	LD	DE,HCB_LOC	; DEST HBIOS HCB ADDRESS
-	LD	BC,HCB_SIZ	; ONE PAGE IN LENGTH
-	CALL	HB_BNKCPY	; DO IT
-	CALL	XIO_DOT		; MARK PROGRESS
-;
-;
-; INITIALIZE HBIOS
-;
-	CALL	XIO_SYNC	; FLUSH OUTPUT FIFO
-	LD	A,BID_BIOS	; HBIOS BANK
-	LD	HL,0		; ADDRESS 0 IS HBIOS INIT ENTRY ADDRESS
-	CALL	HB_BNKCALL	; DO IT
-;
-; CHAIN TO OS LOADER
-;
-#IFDEF ROMLOAD
-	; PERFORM BANK CALL TO OS IMAGES BANK
-	LD	A,BID_OSIMG	; CHAIN TO OS IMAGES BANK
-	LD	HL,0		; ENTER AT ADDRESS 0
-	CALL	HB_BNKCALL	; GO THERE
-	HALT			; WE SHOULD NEVER COME BACK!
-#ELSE
-	; SLIDE OS IMAGES BLOB DOWN TO $0000
-	LD	HL,LDR_END	; SOURCE IS LOADER END
-	LD	BC,HB_END	; PLUS HBIOS IMAGE SIZE
-	ADD	HL,BC		; FINAL SOURCE ADDRESS
-	LD	DE,0		; TARGET ADDRESS IS ZERO
-	LD	BC,BNKTOP	; MAX SIZE OF OS IMAGES
-	LDIR			; DO IT
-	; JUMP TO START
-	JP	0		; AND CHAIN
-#ENDIF
-;
-;==================================================================================================
-;   MEMORY MANAGER
-;==================================================================================================
-;
-#IFDEF ROMLOAD
-#INCLUDE "memmgr.asm"
-#ENDIF
-;
-;==================================================================================================
-;   CLEAN UP
-;==================================================================================================
-;
-	.ORG	$ - P2LOC	; BACK TO IMAGE-BASED ADDRESSING
-LDR_END	.EQU	$		; MARK END OF LOADER