ref: 1440cf9321f07c750c0aba6fccb5dcec057d82f4
parent: 8573d9f7bd0ad311cd2b90c767f11cefd43da371
author: YamaArashi <shadow962@live.com>
date: Sat Feb 4 12:19:24 EST 2012
disasm of number printing functions and other minor changes hg-commit-id: ca84e561db2c
--- a/constants.asm
+++ b/constants.asm
@@ -780,6 +780,12 @@
H_QUOTIENT EQU $FF95 ; 4 bytes, big endian order
H_REMAINDER EQU $FF99 ; 1 byte
+; used to convert numbers to decimal
+H_PASTLEADINGZEROES EQU $FF95 ; flag to indicate that a nonzero digit has been printed
+H_NUMTOPRINT EQU $FF96 ; 3 bytes, big endian order
+H_POWEROFTEN EQU $FF99 ; 3 bytes, big endian order
+H_SAVEDNUMTOPRINT EQU $FF9C ; 3 bytes, big endian order (to back out of a subtraction)
+
; is automatic background transfer during V-blank enabled?
; if nonzero, yes
; if zero, no
--- a/main.asm
+++ b/main.asm
@@ -2846,8 +2846,86 @@
pop hl
ret
-INCBIN "baserom.gbc",$12DA,$1627 - $12DA
+INCBIN "baserom.gbc",$12DA,$15CD - $12DA
+; function to print a BCD (Binary-coded decimal) number
+; de = address of BCD number
+; hl = destination address
+; c = flags and length
+; bit 7: if set, do not print leading zeroes
+; if unset, print leading zeroes
+; bit 6: if set, left-align the string (do not pad empty digits with spaces)
+; if unset, right-align the string
+; bit 5: if set, print currency symbol at the beginning of the string
+; if unset, do not print the currency symbol
+; bits 0-4: length of BCD number in bytes
+; Note that bits 5 and 7 are modified during execution. The above reflects
+; their meaning at the beginning of the functions's execution.
+PrintBCDNumber: ; 15CD
+ ld b,c ; save flags in b
+ res 7,c
+ res 6,c
+ res 5,c ; c now holds the length
+ bit 5,b
+ jr z,.loop\@
+ bit 7,b
+ jr nz,.loop\@
+ ld [hl],$f0 ; currency symbol
+ inc hl
+.loop\@
+ ld a,[de]
+ swap a
+ call PrintBCDDigit ; print upper digit
+ ld a,[de]
+ call PrintBCDDigit ; print lower digit
+ inc de
+ dec c
+ jr nz,.loop\@
+ bit 7,b ; were any non-zero digits printed?
+ jr z,.done\@ ; if so, we are done
+.numberEqualsZero\@ ; if every digit of the BCD number is zero
+ bit 6,b ; left or right alignment?
+ jr nz,.skipRightAlignmentAdjustment\@
+ dec hl ; if the string is right-aligned, it needs to be moved back one space
+.skipRightAlignmentAdjustment\@
+ bit 5,b
+ jr z,.skipCurrencySymbol\@
+ ld [hl],$f0 ; currency symbol
+ inc hl
+.skipCurrencySymbol\@
+ ld [hl],"0"
+ call PrintLetterDelay
+ inc hl
+.done\@
+ ret
+
+PrintBCDDigit: ; 1604
+ and a,%00001111
+ and a
+ jr z,.zeroDigit\@
+.nonzeroDigit\@
+ bit 7,b ; have any non-space characters been printed?
+ jr z,.outputDigit\@
+; if bit 7 is set, then no numbers have been printed yet
+ bit 5,b ; print the currency symbol?
+ jr z,.skipCurrencySymbol\@
+ ld [hl],$f0 ; currency symbol
+ inc hl
+ res 5,b
+.skipCurrencySymbol\@
+ res 7,b ; unset 7 to indicate that a nonzero digit has been reached
+.outputDigit\@
+ add a,"0"
+ ld [hli],a
+ jp PrintLetterDelay
+.zeroDigit\@
+ bit 7,b ; either printing leading zeroes or already reached a nonzero digit?
+ jr z,.outputDigit\@ ; if so, print a zero digit
+ bit 6,b ; left or right alignment?
+ ret nz
+ inc hl ; if right-aligned, "print" a space by advancing the pointer
+ ret
+
;XXX what does this do
;XXX what points to this
Unknown_1627: ; 0x1627
@@ -3376,7 +3454,7 @@
ld b,h
ld c,l
ld hl,Char55Text
- call $1B40
+ call TextCommandProcessor
ld h,b
ld l,c
pop de
@@ -3602,7 +3680,7 @@
ld h,b
ld l,c
ld c,a
- call $15cd
+ call PrintBCDNumber
ld b,h
ld c,l
pop hl
@@ -3690,7 +3768,7 @@
swap a
set 6,a
ld b,a
- call $3c5f
+ call PrintNumber
ld b,h
ld c,l
pop hl
@@ -6348,43 +6426,52 @@
pop hl
FuncCoord 1,14
ld bc,Coord ;$C4B9
- jp $1B40
+ jp TextCommandProcessor
-Func3C5F: ; 3C5F
+; converts a big-endian binary number into decimal and prints it
+; INPUT:
+; b = flags and number of bytes
+; bit 7: if set, do not print leading zeroes
+; if unset, print leading zeroes
+; bit 6: if set, left-align the string (do not pad empty digits with spaces)
+; if unset, right-align the string
+; bits 4-5: unused
+; bits 0-3: number of bytes (only 1 - 3 bytes supported)
+; c = number of decimal digits
+; de = address of the number (big-endian)
+PrintNumber: ; 3C5F
push bc
xor a
- ld [$FF95],a
- ld [$FF96],a
- ld [$FF97],a
+ ld [H_PASTLEADINGZEROES],a
+ ld [H_NUMTOPRINT],a
+ ld [H_NUMTOPRINT + 1],a
ld a,b
- and $F
- cp 1
- jr z,.next\@
- cp 2
- jr z,.next2\@
+ and a,%00001111
+ cp a,1
+ jr z,.oneByte\@
+ cp a,2
+ jr z,.twoBytes\@
+.threeBytes\@
ld a,[de]
- ld [$FF96],a
+ ld [H_NUMTOPRINT],a
inc de
ld a,[de]
- ld [$FF97],a
+ ld [H_NUMTOPRINT + 1],a
inc de
ld a,[de]
- ld [$FF98],a
- jr .next3\@
-
-.next2\@
+ ld [H_NUMTOPRINT + 2],a
+ jr .checkNumDigits\@
+.twoBytes\@
ld a,[de]
- ld [$FF97],a
+ ld [H_NUMTOPRINT + 1],a
inc de
ld a,[de]
- ld [$FF98],a
- jr .next3\@
-
-.next\@
+ ld [H_NUMTOPRINT + 2],a
+ jr .checkNumDigits\@
+.oneByte\@
ld a,[de]
- ld [$FF98],a
-
-.next3\@
+ ld [H_NUMTOPRINT + 2],a
+.checkNumDigits\@
push de
ld d,b
ld a,c
@@ -6391,86 +6478,88 @@
ld b,a
xor a
ld c,a
- ld a,b
- cp 2
- jr z,.next4\@
- cp 3
- jr z,.next5\@
- cp 4
- jr z,.next6\@
- cp 5
- jr z,.next7\@
- cp 6
- jr z,.next8\@
- ld a,$F
- ld [$FF99],a
- ld a,$42
- ld [$FF9A],a
- ld a,$40
- ld [$FF9B],a
- call $3D25
- call $3D89
-.next8\@
- ld a,1
- ld [$FF99],a
- ld a,$86
- ld [$FF9A],a
- ld a,$A0
- ld [$FF9B],a
- call $3D25
- call $3D89
-.next7\@
+ ld a,b ; a = number of decimal digits
+ cp a,2
+ jr z,.tensPlace\@
+ cp a,3
+ jr z,.hundredsPlace\@
+ cp a,4
+ jr z,.thousandsPlace\@
+ cp a,5
+ jr z,.tenThousandsPlace\@
+ cp a,6
+ jr z,.hundredThousandsPlace\@
+.millionsPlace\@
+ ld a,1000000 >> 16
+ ld [H_POWEROFTEN],a
+ ld a,(1000000 >> 8) & $FF
+ ld [H_POWEROFTEN + 1],a
+ ld a,1000000 & $FF
+ ld [H_POWEROFTEN + 2],a
+ call PrintNumber_PrintDigit
+ call PrintNumber_AdvancePointer
+.hundredThousandsPlace\@
+ ld a,100000 >> 16
+ ld [H_POWEROFTEN],a
+ ld a,(100000 >> 8) & $FF
+ ld [H_POWEROFTEN + 1],a
+ ld a,100000 & $FF
+ ld [H_POWEROFTEN + 2],a
+ call PrintNumber_PrintDigit
+ call PrintNumber_AdvancePointer
+.tenThousandsPlace\@
xor a
- ld [$FF99],a
- ld a,$27
- ld [$FF9A],a
- ld a,$10
- ld [$FF9B],a
- call $3D25
- call $3D89
-.next6\@
+ ld [H_POWEROFTEN],a
+ ld a,10000 >> 8
+ ld [H_POWEROFTEN + 1],a
+ ld a,10000 & $FF
+ ld [H_POWEROFTEN + 2],a
+ call PrintNumber_PrintDigit
+ call PrintNumber_AdvancePointer
+.thousandsPlace\@
xor a
- ld [$FF99],a
- ld a,3
- ld [$FF9A],a
- ld a,$E8
- ld [$FF9B],a
- call $3D25
- call $3D89
-.next5\@
+ ld [H_POWEROFTEN],a
+ ld a,1000 >> 8
+ ld [H_POWEROFTEN + 1],a
+ ld a,1000 & $FF
+ ld [H_POWEROFTEN + 2],a
+ call PrintNumber_PrintDigit
+ call PrintNumber_AdvancePointer
+.hundredsPlace\@
xor a
- ld [$FF99],a
+ ld [H_POWEROFTEN],a
xor a
- ld [$FF9A],a
- ld a,$64
- ld [$FF9B],a
- call $3D25
- call $3D89
-.next4\@
- ld c,0
- ld a,[$FF98]
-.next10\@
- cp $A
- jr c,.next9\@
- sub $A
+ ld [H_POWEROFTEN + 1],a
+ ld a,100
+ ld [H_POWEROFTEN + 2],a
+ call PrintNumber_PrintDigit
+ call PrintNumber_AdvancePointer
+.tensPlace\@
+ ld c,00
+ ld a,[H_NUMTOPRINT + 2]
+.loop\@
+ cp a,10
+ jr c,.underflow\@
+ sub a,10
inc c
- jr .next10\@
-.next9\@
+ jr .loop\@
+.underflow\@
ld b,a
- ld a,[$FF95]
+ ld a,[H_PASTLEADINGZEROES]
or c
- ld [$FF95],a
- jr nz,.next11\@
- call $3D83
- jr .next12\@
-.next11\@
- ld a,$F6
- add a,c
+ ld [H_PASTLEADINGZEROES],a
+ jr nz,.pastLeadingZeroes\@
+ call PrintNumber_PrintLeadingZero
+ jr .advancePointer\@
+.pastLeadingZeroes\@
+ ld a,"0"
+ add c
ld [hl],a
-.next12\@
- call $3D89
- ld a,$F6
- add a,b
+.advancePointer\@
+ call PrintNumber_AdvancePointer
+.onesPlace\@
+ ld a,"0"
+ add b
ld [hli],a
pop de
dec de
@@ -6477,8 +6566,126 @@
pop bc
ret
-INCBIN "baserom.gbc",$3D25,$3DAB - $3D25
+; prints a decimal digit
+; This works by repeatedely subtracting a power of ten until the number becomes negative.
+; The number of subtractions it took in order to make the number negative is the digit for the current number place.
+; The last value that the number had before becoming negative is kept as the new value of the number.
+; A more succinct description is that the number is divided by a power of ten
+; and the quotient becomes the digit while the remainder is stored as the new value of the number.
+PrintNumber_PrintDigit: ; 3D25
+ ld c,0 ; counts number of loop iterations to determine the decimal digit
+.loop\@
+ ld a,[H_POWEROFTEN]
+ ld b,a
+ ld a,[H_NUMTOPRINT]
+ ld [H_SAVEDNUMTOPRINT],a
+ cp b
+ jr c,.underflow0\@
+ sub b
+ ld [H_NUMTOPRINT],a
+ ld a,[H_POWEROFTEN + 1]
+ ld b,a
+ ld a,[H_NUMTOPRINT + 1]
+ ld [H_SAVEDNUMTOPRINT + 1],a
+ cp b
+ jr nc,.noBorrowForByte1\@
+.byte1BorrowFromByte0\@
+ ld a,[H_NUMTOPRINT]
+ or a,0
+ jr z,.underflow1\@
+ dec a
+ ld [H_NUMTOPRINT],a
+ ld a,[H_NUMTOPRINT + 1]
+.noBorrowForByte1\@
+ sub b
+ ld [H_NUMTOPRINT + 1],a
+ ld a,[H_POWEROFTEN + 2]
+ ld b,a
+ ld a,[H_NUMTOPRINT + 2]
+ ld [H_SAVEDNUMTOPRINT + 2],a
+ cp b
+ jr nc,.noBorrowForByte2\@
+.byte2BorrowFromByte1\@
+ ld a,[H_NUMTOPRINT + 1]
+ and a
+ jr nz,.finishByte2BorrowFromByte1\@
+.byte2BorrowFromByte0\@
+ ld a,[H_NUMTOPRINT]
+ and a
+ jr z,.underflow2\@
+ dec a
+ ld [H_NUMTOPRINT],a
+ xor a
+.finishByte2BorrowFromByte1\@
+ dec a
+ ld [H_NUMTOPRINT + 1],a
+ ld a,[H_NUMTOPRINT + 2]
+.noBorrowForByte2\@
+ sub b
+ ld [H_NUMTOPRINT + 2],a
+ inc c
+ jr .loop\@
+.underflow2\@
+ ld a,[H_SAVEDNUMTOPRINT + 1]
+ ld [H_NUMTOPRINT + 1],a
+.underflow1\@
+ ld a,[H_SAVEDNUMTOPRINT]
+ ld [H_NUMTOPRINT],a
+.underflow0\@
+ ld a,[H_PASTLEADINGZEROES]
+ or c
+ jr z,PrintNumber_PrintLeadingZero
+ ld a,"0"
+ add c
+ ld [hl],a
+ ld [H_PASTLEADINGZEROES],a
+ ret
+; prints a leading zero unless they are turned off in the flags
+PrintNumber_PrintLeadingZero: ; 3D83
+ bit 7,d ; print leading zeroes?
+ ret z
+ ld [hl],"0"
+ ret
+
+; increments the pointer unless leading zeroes are not being printed,
+; the number is left-aligned, and no nonzero digits have been printed yet
+PrintNumber_AdvancePointer: ; 3D89
+ bit 7,d ; print leading zeroes?
+ jr nz,.incrementPointer\@
+ bit 6,d ; left alignment or right alignment?
+ jr z,.incrementPointer\@
+ ld a,[H_PASTLEADINGZEROES]
+ and a
+ ret z
+.incrementPointer\@
+ inc hl
+ ret
+
+; calls a function from a table of function pointers
+; INPUT:
+; a = index within table
+; hl = address of function pointer table
+CallFunctionInTable: ; 3D97
+ push hl
+ push de
+ push bc
+ add a
+ ld d,0
+ ld e,a
+ add hl,de
+ ld a,[hli]
+ ld h,[hl]
+ ld l,a
+ ld de,.returnAddress\@
+ push de
+ jp [hl]
+.returnAddress\@
+ pop bc
+ pop de
+ pop hl
+ ret
+
IsInArray: ; 3DAB
; searches an array at hl for the value in a.
; skips (de − 1) bytes between reads, so to check every byte, de should be 1.
@@ -36322,7 +36529,7 @@
ld hl,$C3A9
ld de,$D11E
ld bc,$8103
- call $3C5F
+ call PrintNumber
FuncCoord 5,2
ld hl,Coord
ld de,$CF4B
@@ -36334,7 +36541,7 @@
ld hl,$C420
ld de,$CD4C
ld bc,$8205
- jp $3C5F
+ jp PrintNumber
FuncCoord 5,10
ld hl,Coord
@@ -36347,7 +36554,7 @@
ld hl,$C471
ld de,$D11E
ld bc,$8103
- call $3C5F
+ call PrintNumber
FuncCoord 5,12
ld hl,Coord
ld de,$CD6D
@@ -36359,7 +36566,7 @@
ld hl,$C4E8
ld de,$CD59
ld bc,$8205
- jp $3C5F
+ jp PrintNumber
OTString67E5: ; 67E5
db "──",$74,$F2,$4E
@@ -46263,17 +46470,17 @@
ld c,(1 << 7 | 2)
; Function $15CD displays BCD value (same routine
; used by text-command $02)
- call $15CD ; Print_BCD
+ call PrintBCDNumber ; Print_BCD
ld de,$D143
FuncCoord 13,7
ld hl,Coord
ld c,(%1 << 7 | 2)
- call $15CD
+ call PrintBCDNumber
ld de,$D145
FuncCoord 13,9
ld hl,Coord
ld c,(1 << 7 | 2)
- jp $15CD
+ jp PrintBCDNumber
PrizeDifferentMenuPtrs: ; 14:6843
dw PrizeMenuMon1Entries
@@ -46364,7 +46571,7 @@
ld hl,Coord
ld de,W_PLAYERCOINS1
ld c,%10000010
- call $15CD
+ call PrintBCDNumber
ret
.CoinText\@ ; 14:68A5