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rnd.s
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rnd.s
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.segment "CODE"
; ----------------------------------------------------------------------------
; "RND" FUNCTION
; ----------------------------------------------------------------------------
.ifdef KBD
RND:
ldx #$10
jsr SIGN
beq LFC26
bmi LFC10
lda RNDSEED
ldy RNDSEED+1
LFBFA:
sta FAC+2
sty FAC+1
LFBFE:
asl a
asl a
eor FAC+2
asl a
eor FAC+1
asl a
asl a
asl a
asl a
eor FAC+1
asl a
rol FAC+2
rol FAC+1
LFC10:
lda FAC+2
dex
bne LFBFE
sta RNDSEED
sta FAC+3
lda FAC+1
sta RNDSEED+1
lda #$80
sta FAC
stx FACSIGN
jmp NORMALIZE_FAC2
LFC26:
ldy $03CA
lda $03C7
ora #$01
GOMOVMF:
bne LFBFA
.byte $F0
.else
; <<< THESE ARE MISSING ONE BYTE FOR FP VALUES >>>
; (non CONFIG_SMALL)
CONRND1:
.byte $98,$35,$44,$7A
CONRND2:
.byte $68,$28,$B1,$46
RND:
jsr SIGN
.ifdef CONFIG_CBM_ALL
bmi L3F01
bne LDF63
lda ENTROPY
sta FAC+1
lda ENTROPY+4
sta FAC+2
lda ENTROPY+1
sta FAC+3
lda ENTROPY+5
sta FAC+4
jmp LDF88
LDF63:
.else
tax
bmi L3F01
.endif
lda #<RNDSEED
ldy #>RNDSEED
jsr LOAD_FAC_FROM_YA
.ifndef CONFIG_CBM_ALL
txa
beq RTS19
.endif
lda #<CONRND1
ldy #>CONRND1
jsr FMULT
lda #<CONRND2
ldy #>CONRND2
jsr FADD
L3F01:
ldx FAC_LAST
lda FAC+1
sta FAC_LAST
stx FAC+1
.ifdef CONFIG_CBM_ALL
ldx FAC+2
lda FAC+3
sta FAC+2
stx FAC+3
LDF88:
.endif
lda #$00
sta FACSIGN
lda FAC
sta FACEXTENSION
lda #$80
sta FAC
jsr NORMALIZE_FAC2
ldx #<RNDSEED
ldy #>RNDSEED
GOMOVMF:
jmp STORE_FAC_AT_YX_ROUNDED
.endif
.segment "CHRGET"
; ----------------------------------------------------------------------------
; INITIAL VALUE FOR RANDOM NUMBER, ALSO COPIED
; IN ALONG WITH CHRGET, BUT ERRONEOUSLY:
; <<< THE LAST BYTE IS NOT COPIED >>>
; (on all non-CONFIG_SMALL)
; ----------------------------------------------------------------------------
GENERIC_RNDSEED:
.ifndef KBD
; random number seed
.ifdef CONFIG_SMALL
.byte $80,$4F,$C7,$52
.else
.ifdef CONFIG_11
.byte $80,$4F,$C7,$52,$58
.else
.byte $80,$4F,$C7,$52,$59
.endif
.endif
.endif
GENERIC_CHRGET_END: