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saves 2 bytes in the standard c64 joystick driver

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remove redundant code and add jmp to the common sequence
two more bytes could be saved at the expense of longer sequence with interrupts disabled by moving sei/cli
This commit is contained in:
Gabriele Gorla 2021-09-08 15:00:20 -07:00 committed by Oliver Schmidt
parent f796c26091
commit 6637e28831
1 changed files with 2 additions and 6 deletions
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8
libsrc/c64/joy/c64-stdjoy.s
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@ -93,9 +93,7 @@ joy1: lda #$7F
sta CIA1_PRA
lda CIA1_PRB
cli
and #$1F
eor #$1F
rts
jmp end
; Read joystick 2
@ -107,8 +105,6 @@ joy2: ldx #0
lda CIA1_PRA
sty CIA1_DDRA
cli
and #$1F
end: and #$1F
eor #$1F
rts