WeeGUI/utility.s
blondie7575 5202ddbeb7 Added support for variables in widget titles
Views, buttons, and checkboxes can now all use Applesoft string variables in their title parameters. Hardcoded literals still work as well.

Also generalized the string pool allocator and added support for allocating pascal strings.
2017-12-20 12:41:34 -08:00

239 lines
4.0 KiB
ArmAsm

;
; utility.s
; General utilities for 6502
;
; Created by Quinn Dunki on 8/15/14.
; Copyright (c) 2014 One Girl, One Laptop Productions. All rights reserved.
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; delayShort
; Sleeps for ~1/30th second
;
delayShort:
SAVE_AXY
ldy #$06 ; Loop a bit
delayShortOuter:
ldx #$ff
delayShortInner:
nop
nop
nop
nop
nop
nop
nop
dex
bne delayShortInner
dey
bne delayShortOuter
RESTORE_AXY
rts
.if 0
;;;;;;;;;;;;;;;;;;;;;;;
; scanHexDigit
; Scans a 4 bit hex value from an ASCII character
; A: ASCII character
; Out A: Hex value
;
scanHexDigit:
cmp #'a'
bcs scanHexDigitLowCase
cmp #'A'
bcs scanHexDigitLetter
sec
sbc #'0'
jmp scanHexDigitDone
scanHexDigitLowCase:
sec
sbc #32
scanHexDigitLetter:
sec
sbc #55
scanHexDigitDone:
rts
;;;;;;;;;;;;;;;;;;;;;;;
; scanHex8
; Scans an 8 bit hex value from a string
; PARAM0: Pointer to string (LSB)
; PARAM1: Pointer to string (MSB)
; Y: Offset into string
; Out A: 8-bit hex value
; Y: One past what we scanned
; Side effects: Clobbers S0
;
scanHex8:
lda (PARAM0),y
jsr scanHexDigit
asl
asl
asl
asl
sta SCRATCH0 ; Stash first digit for later
iny
lda (PARAM0),y
jsr scanHexDigit
ora SCRATCH0
iny ; Be nice and advance Y to end
rts
.endif
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; WGStrLen
; Finds the length of a null-terminated string
; PARAM0: String pointer, LSB
; PARAM1: String pointer, MSB
; Return: A: String length, not including null
;
WGStrLen:
phy
ldy #0
WGStrLen_loop:
lda (PARAM0),y
beq WGStrLen_done
iny
bra WGStrLen_loop
WGStrLen_done:
tya
ply
rts
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; WGAllocStr
; Finds room in our block string allocator
; Return: PARAM0: Stored string, LSB
; PARAM1: Stored string, MSB
; Null if pool is full
; X: Pool index of free space
; Side Effects: Clobbers AX
;
WGAllocStr:
ldx #0
WGAllocStr_findEmptyLoop:
lda WG_STRINGS,x
beq WGAllocStr_done
txa
clc
adc #16 ; String blocks are 16 bytes wide
bcs WGAllocStr_noRoom
tax
bra WGAllocStr_findEmptyLoop
WGAllocStr_noRoom:
lda #0
sta PARAM0
sta PARAM1
WGAllocStr_done:
rts
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; WGStoreStr
; Finds room in our block allocator and copies the given string.
; A: Terminator character
; PARAM0: String pointer, LSB
; PARAM1: String pointer, MSB
; Return: PARAM0: Stored string, LSB
; PARAM1: Stored string, MSB
; Side Effects: Clobbers SA
;
WGStoreStr:
sta WG_SCRATCHA
SAVE_AXY
jsr WGAllocStr
lda PARAM1
beq WGStoreStr_done
ldy #0
phx ; Remember the start of our string
WGStoreStr_copyLoop:
lda (PARAM0),y
cmp WG_SCRATCHA
beq WGStoreStr_terminate
sta WG_STRINGS,x
inx
iny
cpy #15 ; Clip string to maximum block size
bne WGStoreStr_copyLoop
WGStoreStr_terminate:
lda #0 ; Terminate the stored string
sta WG_STRINGS,x
pla ; Return pointer to the start of the block
clc
adc #<WG_STRINGS
sta PARAM0
lda #0
adc #>WG_STRINGS
sta PARAM1
WGStoreStr_done:
RESTORE_AXY
rts
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; WGStorePascalStr
; Finds room in our block allocator and copies the given string.
; X: Length
; PARAM0: String pointer, LSB
; PARAM1: String pointer, MSB
; Return: PARAM0: Stored string, LSB
; PARAM1: Stored string, MSB
; Side Effects: Clobbers SA
;
WGStorePascalStr:
stx WG_SCRATCHA
SAVE_AXY
jsr WGAllocStr
lda PARAM1
beq WGStorePascalStr_done
ldy #0
phx ; Remember the start of our string
WGStorePascalStr_copyLoop:
cpy WG_SCRATCHA
beq WGStorePascalStr_terminate
lda (PARAM0),y
sta WG_STRINGS,x
inx
iny
cpy #15 ; Clip string to maximum block size
bne WGStorePascalStr_copyLoop
WGStorePascalStr_terminate:
lda #0 ; Terminate the stored string
sta WG_STRINGS,x
pla ; Return pointer to the start of the block
clc
adc #<WG_STRINGS
sta PARAM0
lda #0
adc #>WG_STRINGS
sta PARAM1
WGStorePascalStr_done:
RESTORE_AXY
rts