Difference between revisions of "Z80 Routines:Other:DispHL"

Revision as of 06:53, 21 April 2010

Simple and small routines that print the value of z80 register pair hl.

Decimal Unsigned Versions

• First a simple and small to show. Mostly for debugging or simple programs.

;Number in hl to decimal ASCII
;Thanks to z80 Bits
;inputs:	hl = number to ASCII
;example: hl=300 outputs '00300'
;destroys: af, bc, hl, de used
DispHL:
	ld	bc,-10000
	call	Num1
	ld	bc,-1000
	call	Num1
	ld	bc,-100
	call	Num1
	ld	c,-10
	call	Num1
	ld	c,-1
Num1:	ld	a,'0'-1
Num2:	inc	a
	add	hl,bc
	jr	c,Num2
	sbc	hl,bc
	call PUTCHAR
	ret 

;Bonus! DispA routine
;adaptable for a DispA routine or any other 8-bit register
DispA:
	ld h,0
	ld l,a
	jp DispHL

• DispHL especially adapted to games (nifty to RPG)

;DispHL for games
;input: hl=num, d=row,e=col, bc=number of algarisms to skip
;number of numbers' characters to display: 5 ; example: 65000
;output: hl displayed
DispHL_game:
	push bc
	ld (CurRow),de
	ld de,OP1
	push de
	push de		;save twice...
	call Num2Dec    ;subroutine
	ex de,hl
	ld (hl),0
	pop hl
	jr firsttime
nozerodisp:
	ld (hl),' '	;suppress starting zeros, but you can delete this code if you don't want it
	inc hl
firsttime:
	ld a,(hl)
	cp '0'
	jr z,nozerodisp
	pop hl
	pop bc
	add hl,bc
	call PUTSTR		;b_call(_PutS)
	ret

Num2Dec:
	ld	bc,-10000
	call	Num1
	ld	bc,-1000
	call	Num1
	ld	bc,-100
	call	Num1
	ld	c,-10
	call	Num1
	ld	c,-1
Num1:	ld	a,'0'-1
Num2:	inc	a
	add	hl,bc
	jr	c,Num2
	sbc	hl,bc
	ld	(de),a
	inc	de
	ret 

Hexadecimal Version

;Display a 16- or 8-bit number in hex.
DispHLhex:
; Input: HL
   ld  c,h
   call  OutHex8
   ld  c,l
OutHex8:
; Input: C
   ld  a,c
   rra
   rra
   rra
   rra
   call  Conv
   ld  a,c
Conv:
   and  $0F
   add  a,$90
   daa
   adc  a,$40
   daa
   call PUTCHAR  ;replace by bcall(_PutC) or similar
   ret
 

Decimal Signed Version

;DispHL signed
;
DispHLsign: