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; converts the two-digit BCD number provided in a to text (ascii) format,
; writes them to [wStringBuffer] and [wStringBuffer + 1], and to the BGMap0 address at bc
WriteTwoDigitBCDNumber:
push hl
push bc
push de
ld hl, wStringBuffer
push hl
push bc
call WriteBCDNumberInTextFormat
pop bc
call BCCoordToBGMap0Address
pop hl
ld b, 2
call JPHblankCopyDataHLtoDE
pop de
pop bc
pop hl
ret
; converts the one-digit BCD number provided in the lower nybble of a to text
; (ascii) format, and writes it to [wStringBuffer] and to the BGMap0 address at bc
WriteOneDigitBCDNumber:
push hl
push bc
push de
ld hl, wStringBuffer
push hl
push bc
call WriteBCDDigitInTextFormat
pop bc
call BCCoordToBGMap0Address
pop hl
ld b, 1
call JPHblankCopyDataHLtoDE
pop de
pop bc
pop hl
ret
; converts the four-digit BCD number provided in h and l to text (ascii) format,
; writes them to [wStringBuffer] through [wStringBuffer + 3], and to the BGMap0 address at bc
WriteFourDigitBCDNumber:
push hl
push bc
push de
ld e, l
ld d, h
ld hl, wStringBuffer
push hl
push bc
ld a, d
call WriteBCDNumberInTextFormat
ld a, e
call WriteBCDNumberInTextFormat
pop bc
call BCCoordToBGMap0Address
pop hl
ld b, 4
call JPHblankCopyDataHLtoDE
pop de
pop bc
pop hl
ret
; given two BCD digits in the two nybbles of register a,
; write them in text (ascii) format to hl (most significant nybble first).
; numbers above 9 end up converted to half-width font tiles.
WriteBCDNumberInTextFormat:
push af
swap a
call WriteBCDDigitInTextFormat
pop af
; fallthrough
; given a BCD digit in the (lower nybble) of register a, write it in text (ascii)
; format to hl. numbers above 9 end up converted to half-width font tiles.
WriteBCDDigitInTextFormat:
and $0f
add "0"
cp "9" + 1
jr c, .write_num
add $07
.write_num
ld [hli], a
ret
; converts the one-byte number at a to text (ascii) format,
; and writes it to [wStringBuffer] and the BGMap0 address at bc
WriteOneByteNumber:
push bc
push hl
ld l, a
ld h, $00
ld de, wStringBuffer
push de
push bc
ld bc, -100
call TwoByteNumberToText.get_digit
ld bc, -10
call TwoByteNumberToText.get_digit
ld bc, -1
call TwoByteNumberToText.get_digit
pop bc
call BCCoordToBGMap0Address
pop hl
ld b, 3
call JPHblankCopyDataHLtoDE
pop hl
pop bc
ret
; converts the two-byte number at hl to text (ascii) format,
; and writes it to [wStringBuffer] and the BGMap0 address at bc
WriteTwoByteNumber:
push bc
ld de, wStringBuffer
push de
call TwoByteNumberToText
call BCCoordToBGMap0Address
pop hl
ld b, 5
call JPHblankCopyDataHLtoDE
pop bc
ret
; convert the number at hl to text (ascii) format and write it to de
TwoByteNumberToText:
push bc
ld bc, -10000
call .get_digit
ld bc, -1000
call .get_digit
ld bc, -100
call .get_digit
ld bc, -10
call .get_digit
ld bc, -1
call .get_digit
xor a ; TX_END
ld [de], a
pop bc
ret
.get_digit
ld a, "0" - 1
.subtract_loop
inc a
add hl, bc
jr c, .subtract_loop
ld [de], a
inc de
ld a, l
sub c
ld l, a
ld a, h
sbc b
ld h, a
ret
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