- Joined: 11 Dec 2019
- Posts: 32
- Location: United Kingdom
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I WANT TO BUY: PAL SMS1 M4 model, or anything pre-VA3
Posted: Sat Sep 26, 2020 1:47 am
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I specifically want one with the older VDP: 315-5124
You can tell, because later VA3 models (with newer VDP) have Hang On game built in. Earlier consoles just show a message tellng you to insert a cartridge.
I specfically want one that deos NOT have any 4-pin oscillators. According to schematics, earlier SMS1 PAL consoles usually have a 2-pin 53.2mhz quartz crystal, then it has *TWO* divider circuits, using flip flops:
* divide to 10.63mhz for VDP (VDP divides by 3 internally to create CPU clock)
* divide to 4.43mhz for PAL subcarrier
I specifically want to do a video on youtube, showing how to convert this properly to NTSC timings: 10.73mhz VDP clock, and 3.58mhz NTSC subcarrier, with 60hz mode set on the VDP.
Please message me if you have one! I will purchase it from you.
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