Completing simple VDU commands in assembler like VDU 5 is a simple process
mov al, 5
call "oswrch"
but how do you complete more complicated commands like
VDU 25,4,500,500
Can someone please help
Ric
OSWRCH
Re: OSWRCH
They are not really "more complicated". Separating the parameters with commas is equivalent to using individual VDU statements, it's just a shorthand. So your example is exactly equivalent to (but probably slightly faster than):
Code: Select all
VDU 25 : VDU 4 : VDU 500 : VDU 500
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VDU 25 : VDU 4 : VDU 244 : VDU 244
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mov al,25 : call "oswrch"
mov al,4 : call "oswrch"
mov al,244 : call "oswrch"
mov al,244 : call "oswrch"
Code: Select all
mov al,25 : call "oswrch"
mov al,4 : call "oswrch"
mov al,244 : call "oswrch"
mov al,1 : call "oswrch"
mov al,244 : call "oswrch"
mov al,1 : call "oswrch"
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Re: OSWRCH
Thanks Richard
I feel abit silly for asking now because I should have remembered back to the good old days and the 6502 instructions.
Regards Ric
I feel abit silly for asking now because I should have remembered back to the good old days and the 6502 instructions.
Regards Ric
Kind Regards Ric.
6502 back in the day, BB4W 2017 onwards, BBCSDL from 2023
6502 back in the day, BB4W 2017 onwards, BBCSDL from 2023