- Joined: 27 Jun 2020
- Posts: 212
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full proper dual region SMS hack
Posted: Mon Dec 13, 2021 3:25 am
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I have being tinkering with PS1's lately and come up with a few versions of 'psxtal' to cover each model (they differ in clock generation).
Latest one does 5 clocks and auto switches regions for Sub-carrier and GPU frequencies (sense pin)
I was thinking about doing one for the SMS
Out of laziness i thought I'd check here
Does this sound right?
Lift the NTSC/PAL pin on the VDP
feed it either 5v or send it to ground for PAL/NTSC mode
lift the sub.c pin on the encoder, simultaneously flick this between sub carrier freq for PAL/NTSC
Could also do Overclock modes for the main XTAL.
Is it this simple?
I will do a megadrive version too.
Good thing with both is that it's also going to clean up jail bars by having them on an external circuit and not running through the mainboard PCB traces...!
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