IN this forum post: http://www.sleepingelephant.com/ipw-web/bulletin/bb/viewtopic.php?f=2&t=7855 Simon Rowe has disssembled the code in the VIC-1112 adapter. I think it is interesting how much dead code is in the listing: echkout jsr fndflno ; find file beq lb0bf ; branch if file found jmp fe_ntopn ; do file not open error and retirn lb0bf jsr setflch ; set file details from table,X lda fa ; get device number bne lb0c9 ; branch if device is not keyboard jmp fe_ntout ; do not output file error and return lb0c9 cmp #$03 ; compare device number with screen beq lb0d2 ; if screen save output device number and exit bcs lb0d6 ; branch if > screen, IEEE bus device jmp $f321 ; jump to KERNAL to handle RS-232 and tape lb0d2 sta dflto ; save output device number clc ; flag ok rts lb0d6 jmp lb0e8 ; skip dead code nop ; *** dead code *** jmp $f332 ; *** dead code *** cmp #$09 ; *** dead code *** bne lb0e8 ; *** dead code *** jsr lb59d ; *** dead code *** sta dflto ; *** dead code *** clc ; *** dead code *** rts ; *** dead code *** lb0e8 jsr lb40c ; command an IEEE device to LISTEN sta dflto ; save output device number clc ; flag ok rts The author of the post conjectures that the code was lifted from somewhere else, like the PET. Anyone recognize any of the dead code? Jim Message was sent through the cbm-hackers mailing listReceived on 2016-03-12 05:00:11
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