RE: PET 50Hz editor ROMS

>            PET/CBM PET/CBM PET/CBM  8296D   NTSC     PAL
>             60 Hz   50 Hz   50 Hz   50 HZ   60 Hz   50 Hz

               12"     12"     12"     12"     9"?     9"?
                                      other
                                       crt

> reg.  0     49      49      50      58      63      63

> 324243             -01             -04
> 901474     -03   -04-3681  -04                     -04_
> 901498             -01
> 901499     -01
> 970150                                     -07

> V. Lines   333     400     392     339     263     313
> H. Dots    400     400     408     472     512     512
> H. Sync.   19.98    20     19.6    16.95   15.78   15.65
> Char. Rate 0.999     1     0.9996  1.00005 1.00992 1.0016
> Dot Clock  7.992     8     7.9968  8.0004  8.07936 8.0128

Where can i find the dump from 970150? Normaly this must be a version for 9"
crt. For 9" you need 15.625 kHz horizonaly frequency. So the value from
register 0 can be okay.

You know, the first 9" crt needs 15.625 kHz for horizonal sync. (also used
in the first PET without CRTC). The FAT 12" crt needs a higher horizonal
sync. of 20 kHz for a higher voltage. The 12" crt from the 8296 needs only
17 kHz horizonal sync.

All PET/CBM divided the dot clock from a 16 MHz crystal oscillator. Why do
you have these value above?

Martin


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