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Posted By

Majikeyric
on 2016-01-14
09:17:08
 Detect PAL/NTSC ?

Hi!

What is the easiest reliable method to detect the video system ?

Is checking bit 6 of $ff07 sufficient ?

Or counting the max vertical raster position ?

Thanks

Posted By

crock
on 2016-01-14
09:25:01
 Re: Detect PAL/NTSC ?

Read location F33F in the kernal ROM. #$08 for PAL, #$48 for NTSC.

Posted By

gerliczer
on 2016-01-14
11:15:51
 Re: Detect PAL/NTSC ?

Read KERNAL ROM location $FF80. If MSB is 1 the machine should be PAL, if 0 then NTSC.

Posted By

Csabo
on 2016-01-14
12:44:08
 Re: Detect PAL/NTSC ?

Yes, check bit 6 of $FF07 is sufficient, and by far the most common method actually used in code. The other suggestions above can also work.

Posted By

Majikeyric
on 2016-01-16
05:11:44
 Re: Detect PAL/NTSC ?

WOW ! at least 3 ways to detect the video system! great ! happy

Thanks for the information wink

Posted By

Litwr
on 2016-01-16
11:46:35
 Re: Detect PAL/NTSC ?

There are exactly 618 bytes different in PAL and NTSC ROMs. :)



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