Stuff to put a FPGA in a NuBus Macintosh
Go to file
2022-09-21 23:05:23 +02:00
nubus-to-ztex fix messed up timing... 2022-07-14 08:54:23 +02:00
nubus-to-ztex-gateware sync non-sampling with sampling code 2022-09-21 23:05:23 +02:00
Pictures new picture 2022-04-17 11:53:03 +02:00
.gitignore accel in 16/32 ; includes adding MUL to Vex & fixing a FIFO overrun in NuBus in 32 bits mode 2022-06-04 14:55:40 +02:00
README.md upd readme 2022-09-18 09:40:57 +02:00

A FPGA on a NuBus card...

Goal

The goal of this repository is to be able to interface a modern (2021 era) FPGA with a NuBus host, specifically Apple's Macintosh II and Macintosh Quadra.

Current status

First prototype is working in a Quadra 650. It implements a single-screen-resolution, windowboxed multi-resolution, depth-switchable (1/2/4/8/16/32 bits) framebuffer over DVI-in-HDMI-connector (will work with any HDMI-compliant monitor). The framebuffer can be used as secondary/primary/only framebuffer in the machine running OS8.1. Qemu tests indicate this should work with 7.1 & 7.5/7.6 as well.

Some basic acceleration now exists for 8/16/32 bits, doing rectangle screen-to-screen blits and pattern rectangle fills. 1/2/4 bits also has some acceleration, ut only for byte-aligned cases.

There's also a basic RAM Disk using the 248 MiB of SDRAM not used by the framebuffer. So far this is by 32-bits accesses from the host; DMA using 1x block mode is still TBD.