Files
open-roms/c64/kernal/rs232/rs232_count_channels.s
T
2019-10-31 17:16:32 +01:00

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303 B
ArmAsm

//
// Sets .X to number of open RS-232 channels
// Sets Carry if more than one is open
#if HAS_RS232
rs232_count_channels:
ldx #$00
ldy LDTND
!:
dey
bmi close_rs232_search_done
lda FAT, y
cmp #$02
bne !-
inx
bpl !- // branch always
cpx #$02
rts
#endif