X-Git-Url: http://cloudbase.mooo.com/gitweb/ddt180.git/blobdiff_plain/35b535f6ac49b6533a60236bb2cd9f46f2c79c88..c18ba81991314d10f95b00051fd1e3fbcebc8e48:/ddt180.z80

diff --git a/ddt180.z80 b/ddt180.z80
index 0890182..3a445c3 100644
--- a/ddt180.z80
+++ b/ddt180.z80
@@ -29,32 +29,21 @@ current_cseg	defl	$
 
 ; Some greneral definitions
 
-TAB		equ	9
-LF		equ	10
-CR		equ	13
+BS		equ	08h
+TAB		equ	09h
+CR		equ	0dh
+LF		equ	0ah
+DEL		equ	7fh
+CNTRX		equ	'X'-'@'
 
 ; CP/M memory layout
 
 BDOS		equ	5
-dfcb1		equ	05ch
-dfcb2		equ	06ch
-DMA_BUF		equ	080h
 TPA		equ	0100h
 
 ; BDOS function calls
 
-BDOS_CIN	equ	1	;Console Input
-BDOS_COUT	equ	2       ;Console Output
 BDOS_PSTR	equ	9       ;Print String
-BDOS_CBUF	equ	10      ;Read Console Buffer
-BDOS_CSTAT	equ	11      ;Get Console Status
-BDOS_OPEN	equ	15      ;Open File
-BDOS_CLOSE	equ	16      ;Close File
-BDOS_DELETE	equ	19      ;Delete File
-BDOS_READ	equ	20      ;Read Sequential
-BDOS_WRITE	equ	21      ;Write Sequential
-BDOS_CREATE	equ	22      ;Make File
-BDOS_SETDMA	equ	26      ;Set DMA Address
 
 ; ddtz specific definitions
 
@@ -62,7 +51,7 @@ STACK_SIZE	equ	80	;ddtz internal stack
 CONBUF_SIZE	equ	80	;Size of console input buffer
 EXPR_BUF_SIZE	equ	128	;expressen buffer for conditional breakpoints
 BP_CNT		equ	12	;Number of breakpoints
-BP_SIZE		equ	8	;Size of a breakpoint record
+BP_SIZE		equ	4	;Size of a breakpoint record
 
 ;-------------------------------------------------------------------------------
 
@@ -157,24 +146,44 @@ l0093h:
 	ld hl,ddtz_base
 	ld l,000h
 	ld (reg_sp),hl
-	ld a,(dfcb1+1)
-	cp ' '
-	ld hl,0
-	call nz,read_file
+
+	ld hl,(1)		;wboot addr
+	ld de,?const
+	ld b,6
+vini_l:
+	inc	hl
+	inc	hl
+	inc	hl
+	ex	de,hl
+	inc	hl
+	ld	(hl),e
+	inc	hl
+	ld	(hl),d
+	inc	hl
+	ex	de,hl
+	djnz	vini_l
+
 	jr mainloop
 
 	ds	CONBUF_SIZE + 3 - ($ - conbuf)
 
 ;-------------------------------------------------------------------------------
 
+?const:	jp	0		; return console input status
+?conin:	jp	0		; return console input character
+?cono:	jp	0		; send console output character
+?list:	jp	0		; send list output character
+?auxo:	jp      0		; send auxiliary output character
+?auxi:	jp      0		; return auxiliary input character
+
 CMDTAB:
 	dw	ERROR ;cmd_@	;examine/substitute the displacement register @
 	dw	ERROR ;cmd_A	;Assemble
 	dw	cmd_B		;Breakpoints display/set/clear
-	dw	cmd_C		;trace over Calls
+	dw	ERROR ;cmd_C	;trace over Calls
 	dw	cmd_D		;Display memory in hex and ascii
 	dw	ERROR		;
-	dw	cmd_F		;specify Filename and command line
+	dw	ERROR ;cmd_F	;specify Filename and command line
 	dw	cmd_G		;Go
 	dw	cmd_H		;compute Hex and other expressions
 	dw	cmd_I		;Input a byte from port
@@ -191,7 +200,7 @@ CMDTAB:
 	dw	cmd_T		;Trace
 	dw	ERROR		;
 	dw	cmd_V		;Verify (compare) two memory areas
-	dw	cmd_W		;Write a file to disk
+	dw	ERROR ;cmd_W	;Write a file to disk
 	dw	cmd_X		;eXamine [and substitute] registers
 	dw	ERROR ;cmd_Y	;examine [and substitute] Y variables
 	dw	cmd_Z		;Zap (fill) memory with a byte string
@@ -208,6 +217,7 @@ mainloop:
 	call bp_clr_temporary
 	ld hl,(cmd_rpt)
 	ld de,mainloop
+	push de
 	call cp_hl_de
 	ld a,'>'
 	call outchar
@@ -216,7 +226,8 @@ mainloop:
 	call get_line
 	call skipbl
 	jr z,exe_hl
-	ld hl,mainloop
+	pop hl
+	push hl
 	ld (cmd_rpt),hl
 	inc de
 	sub '@'
@@ -230,19 +241,17 @@ mainloop:
 	inc hl
 	ld h,(hl)
 	ld l,a
-
 exe_hl:
-	call CALL_HL
-	jr mainloop
+	jp (hl)
 
 ;-------------------------------------------------------------------------------
 
 crlf:
 	call	pstr_inl
 	dc	CR,LF
-	call inchar
-	ld a,0
+	xor a
 	ld (con_col),a
+	call inchar
 	jr c,mainloop
 	ret
 
@@ -371,9 +380,8 @@ outchar:
 	push bc
 	push af
 	and 07fh
-	ld e,a
-	ld c,BDOS_COUT
-	call ddtz_bdos
+	ld	c,a
+	call	?cono
 	ld hl,con_col
 	inc (hl)
 	pop af
@@ -390,7 +398,6 @@ pstr:
 	and a
 	ret z
 	call outchar
-	and a
 	ret m
 	jr pstr
 
@@ -410,41 +417,114 @@ p_goto_col:
 
 ;-------------------------------------------------------------------------------
 
+incharw:
+	call inchar
+	jr nc,incharw
+	ret
+
+;-------------------------------------------------------------------------------
+
 inchar:
 	push ix
 	push hl
 	push de
 	push bc
-	ld c,BDOS_CSTAT
-	call ddtz_bdos
+	call	?const
 	and a
-	jr z,l0284h
-	ld c,BDOS_CIN
-	call ddtz_bdos
+	jr	z,inch1
+	call	?conin
 	scf
-l0284h:
+inch1:
 	pop bc
 	pop de
 	pop hl
 	pop ix
 	ret
 
+;-------------------------------------------------------------------------------
+
+DELC:
+	ld	a,b
+	or	a
+	ret	z
+	call	DELC1
+	dec	hl
+	dec	b
+	inc	c
+	ld	a,(hl)
+	cp	' '
+	ret	nc
+DELC1:
+	call	pstr_inl
+	dc	BS,' ',BS
+	ret
+
+DELL:
+	ld a,b			;
+	or a			;
+	ret z			;
+	call DELC		;
+	jr DELL			;
+
+;-------------------------------------------------------------------------------
+
 get_line:
-	push hl
-	ld de,conbuf
-	ld c,BDOS_CBUF
-	call ddtz_bdos
-	call crlf
-	ld hl,conbuf+1
-	ld	e,(hl)
-	xor	a
-	ld	d,a
+	push hl			;
+	ld hl,conbuf		;
+	ld c,(hl)		;
+	inc hl			;
+	ld b,000h		;
+	inc hl			;
+inlnxtch:
+	ld a,c			;
+	or a			;
+	jr z,inl_e		;
+	call incharw		;
+	cp CR			;
+	jr z,inl_e		;Accept line
+	cp LF			;
+	jr z,inl_e		;Accept line
+
+	cp BS			;
+	jr z,gl_1		;
+	cp DEL			;
+	jr nz,gl_2		;
+gl_1:
+	call DELC		;Delete Char
+	jr inlnxtch		;
+gl_2:
+	cp CNTRX		;
+	jr nz,gl_3		;
+	call DELL		;Delete Line
+	jr inlnxtch		;
+gl_3:
+	cp TAB			;
+	jr nz,gl_4		;
+	ld a,' '		;
+gl_4:
+	ld (hl),a		;
+	cp ' '			;
+	jr nc,gl_5		;
+	ld a,'^'		;Controll characters
+	call outchar		;
+	ld a,(hl)		;
+	add a,'@'		;
+gl_5:
+	call outchar		;
+	inc hl			;
+	inc b			;
+	dec c			;
+	jr inlnxtch		;
+
+inl_e:
+	ld (hl),0
+	ld hl,conbuf+1		;
+	ld (hl),b		;
+	call CRLF		;
 	inc	hl
 	ex	de,hl
-	add	hl,de
-	ld	(hl),a
-	pop hl
-	ret
+	pop hl			;
+	ret			;
 
 ;-------------------------------------------------------------------------------
 
@@ -465,17 +545,20 @@ skipbl0:
 	inc de
 skipbl:
 	call get_char_upper
-	call test_whitespace
+	cp ' '
+	jr z,skipbl0
+	cp TAB
 	jr z,skipbl0
 	or a
 	ret
 
+;-------------------------------------------------------------------------------
+
 next_arg:
 	call skipbl
 	cp ','
 	ret nz
-	inc de
-	call skipbl
+	call skipbl0
 	cp a
 	ret
 
@@ -1189,6 +1272,7 @@ p_cpustat:
 l063eh:
 	call p_regs
 	djnz l063eh
+	call outbl6
 	push hl
 	push de
 	ld iy,(reg.pc)
@@ -1261,12 +1345,6 @@ p_regs:
 	inc hl
 	ld d,(hl)
 	ex de,hl
-	dec a
-	jr z,l06d9h
-	call out_hl
-	call z,outbl6
-	jr l06e2h
-l06d9h:
 	call out_hl
 	jr l06e2h
 l06deh:
@@ -1329,7 +1407,6 @@ b_0709_start:
 
 cmd_G:
 	sub a
-	ld (trace_call_flag),a
 	ld (bp_p_cpu_flag),a
 	call expr
 	jr c,l0740h
@@ -1374,7 +1451,6 @@ bp_clr_temporary:
 	ld a,(ix+000h)
 	and 0f1h
 	ld (ix+000h),a
-	call bp_clr_condition
 
 	call bpl_next
 	ret
@@ -1386,11 +1462,10 @@ bp_clr_temporary:
 ;      set breakpoints
 ; > BX
 ;      clear all breakpoints
-; > BX address [address..]
+; > BX breakp [breakp..]
 ;      clear breakpoints
 ;
-; where breakp is:
-;      [R] expression [I condition]
+; breakp can be any valid expression
 
 cmd_B:
 	call skipbl
@@ -1427,45 +1502,27 @@ bp_clr:
 	jr nz,l07aeh
 l07a7h:
 	ld (ix+000h),000h
-	call bp_clr_condition
 l07aeh:
 	pop af
 	call bpl_next
 	ret
 
 bp_print:
+	ld	c,0
 	call	bpl_init
 
 	bit 0,(ix+000h)
 	jr z,bp_pr_cont
-	ld a,'R'
-	bit 4,(ix+000h)
-	jr nz,l07cdh
-	ld a,' '
-l07cdh:
-	call outchar
-	call outbl
 	ld l,(ix+002h)
 	ld h,(ix+003h)
 	call out_hl
-	call 	pstr_inl
-	dc	'  :'
-	ld l,(ix+004h)
-	ld h,(ix+005h)
-	call out_hl
-	ld l,(ix+006h)
-	ld h,(ix+007h)
-	ld a,h
-	or l
-	jr z,l0805h
-	call outbl4
-	call	pstr_inl
-	dc	'I  '
-	call pstr
-l0805h:
-	call crlf
+	call outbl2
+	inc	c
 bp_pr_cont:
 	call bpl_next
+	ld	a,c
+	or	a
+	call 	nz,crlf
 	ret
 
 ;-------------------------------------------------------------------------------
@@ -1477,11 +1534,7 @@ bp_enter:
 	ld b,a
 	call skipbl
 	ret z
-	cp 'R'
-	jr nz,bp_e_1
-	inc de
-	set 4,b
-bp_e_1:
+
 	push bc
 	call expr
 	jr c,error12
@@ -1496,12 +1549,6 @@ bp_e_1:
 	pop de
 	ld (ix+002h),l
 	ld (ix+003h),h
-	call bp_get_count
-	ld (ix+004h),l
-	ld (ix+005h),h
-	call bp_get_condition
-	ld (ix+006h),l
-	ld (ix+007h),h
 	call next_arg
 	pop af
 	ld (ix+000h),a
@@ -1519,48 +1566,6 @@ bp_get_freeslot:
 error12
 	jp ERROR
 
-bp_get_count:
-	call skipbl
-	ld hl,1
-	cp ':'
-	ret nz
-	inc de
-	call expr
-	jr c,error12
-	ret
-
-bp_get_condition:
-	call skipbl
-	cp 'I'
-	ld hl,0
-	ret nz
-	inc de
-	call skipbl
-	push de
-	call expr
-	jr c,error12
-	ex de,hl
-	pop de
-	push de
-	sbc hl,de
-	ld b,h
-	ld c,l
-	ld hl,(expr_p1)
-	push hl
-	add hl,bc
-	ld de,expr_bufe
-	call cp_hl_de
-	jr nc,error12
-	pop	de
-	pop	hl
-	push	de
-	ldir
-	ex de,hl
-	ld (hl),c		; trailing 0
-	inc hl
-	ld (expr_p1),hl
-	pop	hl
-	ret
 
 ;-------------------------------------------------------------------------------
 ; Breakpoint handling routine.
@@ -1628,46 +1633,14 @@ sub_0913h:
 	ld d,(ix+003h)
 	ld hl,(reg.pc)
 	call cp_hl_de
-	push bc
-	call z,sub_0942h
-	pop bc
-l0938h:
-
-	call	bpl_next
-	ex af,af'
-	ret
-
-sub_0942h:
+	jr nz,l0938h
 	ex af,af'
 	res 7,a
-	ex af,af'
-	ld e,(ix+006h)
-	ld d,(ix+007h)
-	ld a,d
-	or e
-	ld hl,0ffffh
-	call nz,expr
-	ld a,h
-	or l
-	jr z,l0969h
-	ld e,(ix+004h)
-	ld d,(ix+005h)
-	dec de
-	ld a,d
-	or e
-	jr z,l0974h
-	ld (ix+004h),e
-	ld (ix+005h),d
-l0969h:
-	bit 4,(ix+000h)
-	ret z
-	ld a,001h
-	ld (bp_p_cpu_flag),a
-	ret
-l0974h:
-	ex af,af'
 	or (ix+000h)
 	ex af,af'
+l0938h:
+	call	bpl_next
+	ex af,af'
 	ret
 
 bp_restore_mem:
@@ -1708,12 +1681,8 @@ bp_tst_e:
 
 bp_trace_enter:
 	call bp_get_freeslot
-	ld (ix+004h),001h
-	ld (ix+005h),000h
 	ld (ix+002h),l
 	ld (ix+003h),h
-	ld (ix+006h),000h
-	ld (ix+007h),000h
 	ld a,(b_21e2_start)
 	and a
 	ld a,008h
@@ -1785,60 +1754,6 @@ l0a41h:
 	ld sp,(reg_sp)
 	jp reg.iff
 
-;-------------------------------------------------------------------------------
-
-bp_clr_condition:
-	ld a,(ix+000h)
-	and 003h
-	ret nz
-	ld e,(ix+006h)
-	ld d,(ix+007h)
-	ld a,d
-	or e
-	ret z
-	push bc
-	ld h,d
-	ld l,e
-	sub a
-	ld (ix+006h),a
-	ld (ix+007h),a
-	ld bc,0ffffh
-	cpir
-l0a7dh:
-	push de
-	ld de,(expr_p1)
-	call cp_hl_de
-	pop de
-	jr nc,l0a93h
-	call sub_0a99h
-l0a8bh:
-	ld a,(hl)
-	ldi
-	and a
-	jr nz,l0a8bh
-	jr l0a7dh
-l0a93h:
-	ld (expr_p1),de
-	pop bc
-	ret
-
-sub_0a99h:
-	ld iy,bp_tab
-	push de
-l0a9eh:
-	ld e,(iy+006h)
-	ld d,(iy+007h)
-	call cp_hl_de
-	jr z,l0ab0h
-	ld de,BP_SIZE
-	add iy,de
-	jr l0a9eh
-l0ab0h:
-	pop de
-	ld (iy+006h),e
-	ld (iy+007h),d
-	ret
-
 ;-------------------------------------------------------------------------------
 ; > Y
 ;      examine all Y variables
@@ -1869,7 +1784,6 @@ cmd_X:
 	ex de,hl
 	ld hl,t_reg_names
 	call sel_dc_string
-l0c12h:
 	call l0c33h
 
 	call outbl
@@ -2130,7 +2044,6 @@ l0d8ah:
 ;      Input a byte from port
 
 cmd_I:
-	ld hl,cmd_I
 	ld (cmd_rpt),hl
 	ld hl,(last_I)
 	call get_lastarg_def
@@ -2150,7 +2063,6 @@ cmd_I:
 ;      Output a byte to a port
 
 cmd_O:
-	ld hl,cmd_O
 	ld (cmd_rpt),hl
 	ld hl,(last_O_val)
 	call get_arg_def
@@ -2194,29 +2106,17 @@ l0dedh:
 	call crlf
 l0e10h:
 	pop bc
-	inc hl
 	inc de
-	dec bc
-	ld a,b
-	or c
-	jr nz,l0dedh
+	cpi
+	jp pe,l0dedh
 	ret
 
 ;-------------------------------------------------------------------------------
-; > M[V] startaddr endaddr destaddr
-;      Move memory [and verify]
+; > M startaddr endaddr destaddr
+;      Move memory
 
 cmd_M:
-	call get_char_upper
-	cp 'V'
-	jr nz,l0e1fh
-	inc de
-l0e1fh:
-	push af
 	call sub_034eh
-	push hl
-	push de
-	push bc
 	call cp_hl_de
 	jr nc,cmdm_up
 	add hl,bc
@@ -2229,11 +2129,6 @@ l0e1fh:
 	db 01h		;swallow ldir instruction (ld bc,...)
 cmdm_up:
 	ldir
-	pop bc
-	pop de
-	pop hl
-	pop af
-	jr z,l0dedh
 	ret
 
 ;-------------------------------------------------------------------------------
@@ -2242,30 +2137,11 @@ cmdm_up:
 ;      off all loaded files, and Top address of available memory
 ; > H expression
 ;      evaluate expression and display result in hex, decimal and other formats
-; > H expression expression
-;      display sum und difference of expressions
 
 cmd_H:
 	call expr
 	jp c,p_max_high0
-	call next_arg
-	push hl
-	call expr
-	push af
 	call assert_eol
-	pop af
-	ex de,hl
-	pop hl
-	jr c,l0e5eh
-	push hl
-	push de
-	add hl,de
-	call l0e5eh
-	pop de
-	pop hl
-	and a
-	sbc hl,de
-l0e5eh:
 	call out_hl
 	call outbl2
 	call out_hl_neg
@@ -2285,32 +2161,31 @@ l0e5eh:
 ;      Query memory for a byte string [Justified]
 
 cmd_Q:
-	call get_char_upper
-	sub 'J'
-	ld (cmd_Q_jopt),a
-	jr nz,l0e8dh
-	inc de
-l0e8dh:
 	call get_arg_range
 	push bc
 	push hl
 	call sub_0ee6h
 	pop hl
 l0e96h:
-	call sub_0ed7h
+	push	hl
+	push	de
+	push bc
+l0edah:
+	ld a,(de)
+	cp (hl)
+	jr nz,l0ee2h
+	inc de
+	inc hl
+	djnz l0edah
+l0ee2h:
+	pop bc
+	pop de
+	pop hl
 	jr nz,l0eb0h
 	push bc
-	push hl
-	ld a,(cmd_Q_jopt)
-	or a
-	jr nz,l0ea7h
-	ld bc,-8
-	add hl,bc
-l0ea7h:
 	ld bc,16
-	and a
+	and a			;clear carry
 	call sub_0f58h
-	pop hl
 	pop bc
 l0eb0h:
 	inc hl
@@ -2349,23 +2224,6 @@ l0ed3h:
 	pop hl
 	ret
 
-sub_0ed7h:
-	push	hl
-	push	de
-	push bc
-l0edah:
-	ld a,(de)
-	cp (hl)
-	jr nz,l0ee2h
-	inc de
-	inc hl
-	djnz l0edah
-l0ee2h:
-	pop bc
-	pop de
-	pop hl
-	ret
-
 sub_0ee6h:
 	ld hl,conbuf+1
 	call sub_0ef7h
@@ -2376,26 +2234,13 @@ sub_0ee6h:
 	ret nz
 	jp ERROR
 
-sub_0ef7h:
-	db	0e6h		; and 037h (clear carry)
-sub_0ef8h:
+sub_0ef7h:			;from cmd_Q, cmd_Z
+	db	0e6h		;and 037h (clear carry)
+sub_0ef8h:			;from cmd_S
 	scf
 l0ef9h:
 	push af
 	call next_arg
-	cp 'W'
-	jr nz,l0f0eh
-	inc de
-	push hl
-	call sub_035dh
-	ex de,hl
-	ex (sp),hl
-	ld (hl),e
-	inc hl
-	ld a,d
-	pop de
-	jr l0f1ah
-l0f0eh:
 	cp ''''
 	jr z,l0f1eh
 	push hl
@@ -2445,7 +2290,6 @@ l0f42h:
 ;      Display memory in hex and ASCII
 
 cmd_D:
-	ld hl,cmd_D
 	ld (cmd_rpt),hl
 	ld hl,(last_D)
 	ld bc,128
@@ -2458,8 +2302,7 @@ sub_0f58h:
 	push af
 l0f5ch:
 	call out_hl
-	call z,outbl2
-	call outbl
+	call outbl2
 	ld de,0
 l0f68h:
 	ld a,(hl)
@@ -2516,201 +2359,89 @@ l0fach:
 ; > Fcommandline
 ;      specifiy filenames and command line
 
-cmd_F:
+;cmd_F:
+
+;-------------------------------------------------------------------------------
+; > R [displacement]
+;	Read Intel Hex File from console [add displacement]
+
+cmd_R:
+	ld hl,0
+	call get_lastarg_def	;get offset from command line
+	push hl
+	ld hl,0
+	ld (high_load),hl
+w_recstart:
+	call i.getchar
+	jr z,rdhex_done
+	cp ':'
+	jr nz,w_recstart
+	ld c,0			;init checksum
+	call i.gethexbyte	;record len
+	ld b,a
+	call i.gethexbyte	;address high
+	ld h,a
+	call i.gethexbyte	;address low
+	ld l,a
+	call i.gethexbyte	;record type (ignored)
+	ld a,b
+	and a			;record len == 0?
+	jr z,rdhex_done
+l16c6h:
+	call i.gethexbyte
+	pop de			;offset
 	push de
-	ld hl,DMA_BUF+1
-	ld (hl),' '
+	push hl
+	add hl,de
+	call i.storebyte
+	pop hl
 	inc hl
-l0fb6h:
-	call get_char_upper
-	ld (hl),a
-	inc hl
-	inc de
+	djnz l16c6h		;repeat for record len
+	call i.gethexbyte	;checksum
+	ld a,c
 	and a
-	jr nz,l0fb6h
-	ld a,l
-	sub DMA_BUF+2
-	ld (DMA_BUF),a
+	jp nz,ERROR		;exit if checksum error
+	jr w_recstart		;next record
+rdhex_done:
 	pop hl
-	ld de,dfcb1
-	call parse_filename
-	ld de,dfcb2
-	;fall thru
-
-parse_filename:
-	call sub_102ch
-	push de
-	push bc
-	ld b,(hl)
-	inc hl
-	ld a,(hl)
-	cp ':'
-	jr nz,l0fe1h
-	inc hl
-	ld a,b
-	sub 040h
-	and 01fh
-	jr l0fe3h
-l0fe1h:
-	dec hl
-	xor a
-l0fe3h:
-	ld (de),a
-	inc de
-	ld b,8
-	call sub_0ff2h
-	ld b,3
-	call sub_0ff2h
-	pop bc
-	pop de
-	ret
-
-sub_0ff2h:
-	call sub_1012h
-	jr z,l0ffeh
-	inc hl
-	ld (de),a
-	inc de
-	djnz sub_0ff2h
-	jr l1003h
-l0ffeh:
-	ld a,c
-l0fffh:
-	ld (de),a
-	inc de
-	djnz l0fffh
-l1003h:
-	call sub_1012h
-	inc hl
-	jr nz,l1003h
-	cp '*'
-	jr z,l1003h
-	cp '.'
-	ret z
-	dec hl
-	ret
-
-sub_1012h:
-	ld a,(hl)
-	ld c,' '
-	and 01fh
-	ret z
-	ld a,(hl)
-	cp ' '
-	ret z
-	call sub_1043h
-	ret z
-	cp '/'
-	ret z
-	cp '.'
-	ret z
-	ld c,'?'
-	call toupper
-	cp '*'
-	ret
-
-l102bh:
-	inc hl
-sub_102ch:
-	ld a,(hl)
-	cp '/'
-	jr z,l103bh
-	call sub_1043h
-	jr z,l102bh
-l1036h:
-	cp ' '
-	jr z,l102bh
-	ret
-
-l103bh:
-	ld a,(hl)
-	cp ' '+1
-	jr c,l1036h
-	inc hl
-	jr l103bh
-
-sub_1043h:
-	cp '='
-	ret z
-	cp '_'
-	ret z
-	cp ','
-	ret
-
-;-------------------------------------------------------------------------------
+	call i.gethexbyte
+	jp p_max_high
 
-setup_fcb:
-	push de
-	ld hl,12
-	add hl,de
-	xor a
-	ld b,21
-l1052h:
-	ld (hl),a
-	inc hl
-	djnz l1052h
-	ld de,DMA_BUF
-	ld c,BDOS_SETDMA
-	call ddtz_bdos
-	pop de
+i.gethexbyte:
+	call sub_16f6h
+	rlca
+	rlca
+	rlca
+	rlca
+	ld d,a
+	call sub_16f6h
+	add a,d
+	ld d,a
+	add a,c
+	ld c,a
+	ld a,d
 	ret
 
-;-------------------------------------------------------------------------------
-
-file_open:
-	ld (cur_fcb),de
-	call setup_fcb
-	ld c,BDOS_OPEN
-	call ddtz_bdos
-	inc a
-	jp z,ERROR
-	ld a,080h
-	ld (cmdR_rindex),a
-	ret
+sub_16f6h:
+	call i.getchar
+	jr z,error2
+	call hex_digit
+	ret nc
+error2:
+	jp ERROR
 
-read_byte:
-	ld a,(cmdR_rindex)
-	cp 080h
-	jr nz,l1111h
-	call read_sector
-	ld a,01ah
-	ret z
-	sub a
-l1111h:
-	inc a
-	ld (cmdR_rindex),a
-	push hl
-	add a,07fh
-	ld l,a
-	ld h,000h
-	ld a,(hl)
-	pop hl
+i.getchar:
+	call incharw
 	cp 01ah
 	ret
 
-read_sector:
-	push hl
-	push de
-	push bc
-	ld de,(cur_fcb)
-	ld c,BDOS_READ
-	call ddtz_bdos
-	sub a,1
-	jr z,l1132h
-	jr nc,error2
-l1132h:
-	pop bc
-	pop de
-	pop hl
-	ret
-
-cmdR_storebyte:
+i.storebyte:
 	push af
 	push de
-	ld de,TPA
+	ld de,TPA		;lowest allowed load address
 	call cp_hl_de
 	jr c,error2
-	ld de,(BDOS+1)
+	ld de,(BDOS+1)		;highest allowed load address
 	call cp_hl_de
 	jr nc,error2
 	ld de,(high_load)
@@ -2725,125 +2456,7 @@ l1157h:
 l1163h:
 	pop de
 	pop af
-	ld (hl),a
-	ret
-
-strncmp:
-	ld a,(de)
-	cp (hl)
-	inc de
-	inc hl
-	ret nz
-	djnz strncmp
-	ret
-
-str_hex:
-	db	'HEX'
-
-read_hexchar:
-	call read_hexdigit
-	rlca
-	rlca
-	rlca
-	rlca
-	ld d,a
-	call read_hexdigit
-	add a,d
-	ld d,a
-	add a,c
-	ld c,a
-	ld a,d
-	ret
-
-read_hexdigit:
-	call read_byte
-	jr z,error2
-hex_digit_v:
-	call hex_digit
-	ret nc
-error2:
-	jp ERROR
-
-;-------------------------------------------------------------------------------
-; > R [displacement]
-;      Read a binary or hex file  [add displacement]
-
-cmd_R:
-	ld hl,0
-	call get_lastarg_def
-read_file:
-	ld de,dfcb1
-	push hl
-	ld hl,0
-	ld (high_load),hl
-	call file_open
-	ld hl,dfcb1+9
-	ld de,str_hex
-	ld b,3
-	call strncmp
-	pop hl
-	jr z,read_hexfile
-	ld de,TPA
-	push hl
-	add hl,de
-l108eh:
-	call read_sector
-	jr nz,read_file_nxt
-	pop hl
-	jp p_max_high
-
-read_file_nxt:
-	ld de,DMA_BUF
-	ld b,080h
-l109ah:
-	ld a,(de)
-	call cmdR_storebyte
-	inc de
-	inc hl
-	djnz l109ah
-	jr l108eh
-
-read_hexfile:
-	push hl
-l10aeh:
-	call read_byte		; RECORD MARK
-	jr z,rdhex_done
-	cp ':'
-	jr nz,l10aeh
-	ld c,0
-	call read_hexchar	; RECLEN
-	ld b,a
-	call read_hexchar	; LOAD ADDR H
-	ld h,a
-	call read_hexchar	; LOAD ADDR L
-	ld l,a
-	ld a,b
-	and a
-	jr z,rdhex_done
-	call read_hexchar	; RECTYP
-l10cch:
-	call read_hexchar	; DATA
-	pop de
-	push de
-	push hl
-	add hl,de
-	call cmdR_storebyte
-	pop hl
-	inc hl
-	djnz l10cch
-	call read_hexchar	; CHKSUM
-	ld a,c
-	and a
-	jp nz,ERROR
-	jr l10aeh
-rdhex_done:
-	pop hl
-	jp p_max_high
-
-test_whitespace:
-	cp	' '
-	ret	z
-	cp	TAB
+	ld (hl),a		;store byte
 	ret
 
 ;-------------------------------------------------------------------------------
@@ -2869,66 +2482,7 @@ p_max_high:
 ; > Wstartaddr endaddr
 ;      Write a file to disk
 
-cmd_W:
-	call get_arg_range
-	call assert_eol
-	push hl
-	ld a,c
-	add a,07fh
-	jr nc,l11adh
-	inc b
-l11adh:
-	and 080h
-	ld c,a
-	push bc
-	ld a,(dfcb1+1)
-	cp ' '
-	jr z,error4
-	ld de,dfcb1
-	call setup_fcb
-	push de
-	ld c,BDOS_DELETE
-	call ddtz_bdos
-	pop de
-	ld c,BDOS_CREATE
-	call ddtz_bdos
-	inc a
-	jr z,error4
-	pop bc
-	pop hl
-l11cch:
-	ld a,b
-	or c
-	jr z,close_file
-	push bc
-	ld de,080h		; DMA_BUF
-	ld b,d
-	ld c,e
-	ldir
-	call write_sector
-	ex (sp),hl
-	ld bc,0ff80h
-	add hl,bc
-	ex (sp),hl
-	pop bc
-	jr l11cch
-
-write_sector:
-	push hl
-	ld de,dfcb1
-	ld c,BDOS_WRITE
-	call ddtz_bdos
-	pop hl
-	and a
-	ret z
-	call close_file
-error4:
-	jp ERROR
-
-close_file:
-	ld de,dfcb1
-	ld c,BDOS_CLOSE
-	jp ddtz_bdos
+;cmd_W:
 
 ;-------------------------------------------------------------------------------
 ; > A [startaddr]
@@ -2959,7 +2513,6 @@ l1773h:
 ;      List disassembled code
 
 cmd_L:
-	ld hl,cmd_L
 	ld (cmd_rpt),hl
 	call expr
 	jr nc,l18dbh
@@ -4011,7 +3564,7 @@ tc_set_bp:
 	ld de,BDOS
 	and a
 	sbc hl,de
-	ld hl,l20edh
+	ld hl,l20edh		;set break after BDOS call
 	jr z,l2031h
 	ld iy,(reg.pc)
 	call disas_get_instrlen
@@ -4072,12 +3625,6 @@ b_2048_start:
 ;-------------------------------------------------------------------------------
 ; call mn	call cc,mn
 l2080h:
-	ld a,(b_21e2_start)
-	and a
-	jr nz,l208bh
-	ld a,(trace_call_flag)
-	and a
-	ret nz
 
 ; jp mn		jp cc,mn
 l208bh:
@@ -4147,17 +3694,8 @@ l20d7h:
 	jp (hl)
 
 l20dch:
-	ld a,(b_21e2_start)
-	and a
-	jr nz,l20edh
-	ld a,(trace_call_flag)
-	and a
-	jr z,l20edh
-	call l20edh
-	pop hl
-	ret
 l20edh:
-	ld hl,(reg_sp)
+	ld hl,(reg_sp)		;break on return address
 	ld e,(hl)
 	inc hl
 	ld d,(hl)
@@ -4177,11 +3715,8 @@ l20f9h:
 	ld h,000h
 	ld a,(b_21e2_start)
 	and a
-	jr nz,l2113h
-	ld a,(trace_call_flag)
-	and a
-	ret nz
-l2113h:
+	ret z
+
 	scf
 	ret
 
@@ -4191,10 +3726,6 @@ l2113h:
 ; >>C[N][J] U expression
 ;     trace over Calls [No list] [Jumps only] /.While./.Until.
 
-cmd_C:
-	ld hl,cmd_C
-	ld a,1
-	jr cmd_tc
 
 ;-------------------------------------------------------------------------------
 ; >>T[N][J] [steps]
@@ -4203,119 +3734,31 @@ cmd_C:
 ;      Trace [no List] [Jumps only] / .While. / .Until.
 
 cmd_T:
-	xor a
-	ld hl,cmd_T
-cmd_tc:
 	ld (cmd_rpt),hl
-	ld (trace_call_flag),a
-	call get_char_upper
-	sub 'N'
-	jr nz,tc_non
-	inc de
-tc_non:
-	ld (trace_N_flag),a
-	call get_char_upper
-	sub 'J'
-	jr nz,tc_noj
-	inc de
-tc_noj:
-	ld (trace_J_flag),a
-	call tc_chk_u_or_w
-	jr z,tc_save_uw_expr_ptr
 	ld hl,1				;default: 1 step
 	call get_lastarg_def
-tc_save_uw_expr_ptr:
 	ld (trace_cnt_or_ptr),hl
 	sub a
 	ld (bp_p_cpu_flag),a
-l214ch:
 	call tc_set_bp
 	jr user_go1
 
 l2151h:
 	call bp_clr_temporary
-	ld a,(trace_J_flag)
-	and a
-	jr nz,l216bh
-	ld iy,(reg.pc)
-	call sub_21c8h
-	jr z,l216bh
-	ld hl,b_2048_start
-	call lookup_opc
-	jr nc,l214ch
-l216bh:
-	ld a,(trace_UW_flag)		;0 or 'U' or 'W'
-	and a
-	jr z,tc_cnt			;flag is 0, check for step count.
-	ld de,(trace_cnt_or_ptr)
-	call expr
-	ld a,h
-	or l
-	add a,0ffh
-	sbc a,a
-	ld hl,trace_UW_flag		;'U' or 'W'
-	xor (hl)
-	bit 1,a				;'U' = 55H, 'W' = 57H
-	jr z,l2193h
-do_break0:				;print registers and go to main loop
-	jp do_break
-
-tc_cnt:
 	ld hl,(trace_cnt_or_ptr)
 	dec hl
 	ld (trace_cnt_or_ptr),hl
 	ld a,h
 	or l
-	jr z,do_break0
-l2193h:
+	jp z,do_break
+
 	call tc_set_bp
-	jr nc,do_break0
-	ld a,(trace_N_flag)
-	ld b,a
-	ld a,(bp_p_cpu_flag)
-	or b
+	jp nc,do_break
+	sbc a,a
 	ld (bp_p_cpu_flag),a
 user_go1:
 	jp user_go
 
-tc_chk_u_or_w:
-	call skipbl
-	xor a
-	ld (trace_UW_flag),a
-	call get_char_upper
-	cp 'U'
-	jr z,l21b5h
-	cp 'W'
-	ret nz
-l21b5h:
-	inc de
-	push af
-	push de
-	call expr
-	jp c,ERROR
-	call assert_eol
-	pop hl
-	pop af
-	ld (trace_UW_flag),a
-	sub a
-	ret
-
-sub_21c8h:
-	ld a,(iy+000h)
-	cp 0edh
-	jr z,l21dah
-	and 0dfh
-	cp 0ddh
-	ret nz
-	ld a,(iy+001h)
-	cp 0e9h
-	ret
-l21dah:
-	ld a,(iy+001h)
-	and 0f7h
-	cp 045h
-	ret
-
 ;-------------------------------------------------------------------------------
 
 con_col:
@@ -4325,16 +3768,8 @@ con_col:
 
 b_21e2_start:
 	db	0
-trace_call_flag:
-	db	0		;1=call, 0=trace
-trace_UW_flag:
-	db	0		;0 or 'U' or 'W'
 trace_cnt_or_ptr:
 	dw	0
-trace_N_flag:
-	db	0		;0 if 'N'
-trace_J_flag:
-	db	0		;0 if 'J'
 
 bp_p_cpu_flag:
 	db	0
@@ -4346,9 +3781,6 @@ bp_tab:
 	 endm
 	endm
 
-expr_p1:
-	dw	expr_buf
-
 expr_buf:
 current_cseg	defl	$ - current_cseg
 	.phase	current_phase + current_cseg
@@ -4447,15 +3879,9 @@ last_O_addr:
 last_O_val:
 	db	0
 
-cmd_Q_jopt:
-	db	-1
-
 last_D:
 	dw	TPA
 
-cmdR_rindex:
-	db	0
-
 high_load:
 	dw	TPA
 max_load:
@@ -4473,9 +3899,6 @@ disas_argtype:
 pbl_loop_adr:
 	dw	0
 
-cur_fcb:
-	dw	0
-
 ddtz_size	equ	$-ddtz_base
 ddtz_end: