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nand2mario / nestang

NESTang is an FPGA Nintendo Entertainment System implemented with Sipeed Tang Primer 25K, Nano 20K and Primer 20K boards
GNU General Public License v3.0
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Elite rendering issues #77

Open wiebel opened 5 months ago

wiebel commented 5 months ago

This is probably already known, but just in case. Elite's background bitmaps are rendered at an offset of around half a screenheight. I t would be great to be able to play Elite in one of it's original forms. There is probably an mid screen mode switch involved. As it's one of the best documented game codes this might be helpful: https://www.bbcelite.com/nes/ https://github.com/markmoxon/nes-elite-beebasm

nand2mario commented 5 months ago

I'll take a look.

fjpolo commented 4 months ago

AFAIK Elite is PAL and NESTang is NTSC, so that's why it renders like that. Eg: Mr Gimmmick PAL running on NTSC.

Idea: Maybe adding a PAL/NTSC option in Options that changes the CPU clock might fix it? PAL runs at ~1,66[MHz) while NTSC runs at ~1,79[MHz]

fjpolo commented 4 months ago

As I thought, changing system_type to PAL fixes the issue

Logic repo Firmware repo Nano20k release Logic draft PR Firmware draft PR

NTSC

IMG_20240707_222105

PAL

IMG_20240708_134316

Edit: This fix is not in any official PR yet, so won't be part of any official release soon