Gadget:Gen-X

From C256 Foenix Wiki
Revision as of 17:17, 27 June 2023 by Gadget (talk | contribs) (Created page with "Getting Started * Both displays show logos, but only display B is responsive. Startup * On hard-reset, the FPGA copies the first 64k of flash to $0. * Post-upload reset lea...")
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

Getting Started

  • Both displays show logos, but only display B is responsive.

Startup

  • On hard-reset, the FPGA copies the first 64k of flash to $0.
  • Post-upload reset leaves that block alone, so you can upload code there.

Memory

  • MOVE16 presently only works with the SRAM in the first 4BM.
    • This basically means you can't cache anything anywhere else.
    • TODO: test burst mode from the flash (ie can cache and/or keep MMU tables here?)
  • Stef says to avoid using the DRAM for now.

I/O

  • Power and SD Card LED control bits at GAVIN:0000 (feca) don't appear to work.
  • I can't seem to get the LFSR to work.
  • The I/O space should be marked as serialized/no-cache (defaults to unserialized -- reads can get ahead of writes).

vasm

  • The 68040 MOVEC cache and MMU control registers are there, but typically without the last letter (R for Register).