Here’s a really great Papilio project that we wanted to revisit:
The SOCZ80 Retro Computer! Here is some more info:
I built a small FPGA microcomputer for the Papilio Pro board. I’ve ported a few operating systems to run on it. These 8-bit machines have very minimal features but (somewhat unexpectedly) I found they can run a multi-user, multi-tasking UNIX operating system.
The hardware specification is:
- Z80 compatible T80 CPU core at 128MHz
- 4KB paged MMU (64KB virtual, 64MB physical address space)
- 8MB SDRAM (at 128MHz), with 16KB direct-mapped cache
- 4KB ROM with monitor program
- 4KB SRAM
- UART with deep receive FIFO
- Optional second UART with FIFO and hardware flow control
- 1MHz Timer
- SPI master connected to SPI flash ROM
- SPI master connected to optional SD card socket
- GPIO
I’ve ported the following operating systems:
- CP/M-2.2
- MP/M-II
- UZI