add early readme

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chacha
2026-02-23 11:50:25 +01:00
parent d50c3ff48f
commit 7f4ea3d371

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\# Voodoo 2 (TMU) MemTest
This tool is an attempt to help troubleshooting Voodoo² TMU's issues.
TMU system can be very hard to fix because there are so many connexions.
\## TMU0 Memory test
 
  ┌────────────┐ 3 ┌───────────┐
  │ ┼─────► │
  │ TMU0 │ │ TMU0 RAM │
  │ ◄─────┼ │
  └──▲──────┬──┘ └───────────┘
  │ │ 4
  │ │
  2 │ │ 5
  │ │
  ┌──┼──────▼──┐ 6 ┌───────────┐
  │ ┼─────► │
  │ FBI │ │ FBI RAM │
  │ ◄─────┼ │
  └──▲───────┬─┘ 7 └───────────┘
  │ │
  │ │
  1 │ │ 7
  │ │
  ┌──┼───────▼─┐
  │ │
  │ CPU │
  │ │
  └────────────┘
* 1 : CPU configure texture base address and write data to the FBI
* 2 : The FBI streams the texture to the TMU
* 3 : The TMU writes the texture into his private memory
* 4 : The CPU sends a request to the TMU (through the FBI) to render a triangle using this texture (double the size)
* 5 : The TMU streams the rendered pixels to the FBI
* 6 : The FBI writes the pixel to the frame buffer
* 7 : The CPU requests the pixels using the Linear Frame Buffer access
* x : The CPU can compare the rendered value with the original texture