DTC3 - a free hardware project (WARNING: old and unmaintained stuff from here on)

Well, making hardware is not only my job, but also my hobby.
This is a card I produced totally by myself between Oct.1997 and Jan.1998:

Features

DTC3 is an ISA bus card; it contains:

• an FPGA (Xilinx 4013E), directly connected to the PC bus. I really don't like Xilinxes, because they are expensive and there is no free software for them, but that's what I had at hand. If you need a LOT of I/O pins for the various bus interfaces, and a 160PQFP package is barely enough; OTOH, the logic inside will probably never need more than 5000 gates out of the 13000 I have now.
• a Motorola 683xx 32-bit microcontroller, with 16-bit data bus. I used a 68396 because it has a built-in CAN bus interface. Besides that, I use the 683xx at work, so the board is also a sort of development system. There are 256k of static RAM and 2M of flash Eprom on the board. Communications between MCU and PC are handled within the FPGA and are totally programmable on an application basis. There is an expansion connector for analog I/O and TPU pins. The CPU's BDM (Background Debug Mode) interface can be controlled through the FPGA or an external emulator. The CAN bus uses a Philips 82C250 high-speed transceiver.
• two IMSC012 high-speed link adapters, directly controlled by the FPGA. I like these chips, they make for very fast (20Mbit/s) and reliable communication channels, and are still IMHO a good choice, at least until USB and 1394 will become widespread. By rule #1, I had also to keep my old Transputers alive, but this is another story... The pins used by the C012s on the FPGA can be reused for a general-purpose 8-bit parallel interface if you choose not to implement the serial links (what about e.g. interfacing with a TMS320C40?). There is a connector for a size-2 TRAM Transputer module, which can be reused as a general-purpose piggyback.
• a Lattice ispGAL22V10 is used for FPGA control and startup; four Lattice ispGDS22 for programmable interconnections.
• some extra I/O, e.g. 4 digital in+4 outs; I currently use some of them as MIDI outputs after implementing the needed UARTs into the FPGA.

History

There was a DTC1 in 1992, and a DTC2 in 1995. Both were built to concentrate into one single PC slot many functions I previously kept on separate cards, after PC motherboards
introduced PCI support and drastically cut down the number of available ISA slots. DTC2 had a small FPGA, a Transputer and a DSP56002 on a full-size board; I have still one of
such boards, fully functional and unused... can I throw them away or does anyone care?
DTC3 was designed in Nov.1997, built and tested by the end of the year. I only made two boards, as they are quite expensive, at least from an hobbyist's point of view.
There were some unavoidable corrections to the schematics and PCB during the first debugging run, so I'm now at version 1.1 of the schematics. I have not yet rerouted the
PCB, so the one you'll see here is still version 1.0.

Tools

I used Orcad v4 for schematics, UltiBoard v4.9 for the PCB, XACT 5.2.1 for the FPGA. All are DOS-based tools, all require a dongle, all run quite well under linux DOSEMU.
The only freeware tools are the GDS assembler and download cable I used for the Lattice GAL and GDS.

The data

schematics for DTC3 v1.1 (Orcad v4) last updated 1998/1/18

schematics for DTC3 v1.1 (HP Laserjet PCL file)

GAL and GDS equations and tools for current board. The GAL has been done in CUPL, the GDS with Lattice's GDSASM. To download the binary file into the board you need a cable like the one described in the Lattice data book, from the parallel port to the 8-pin linear connector on the board. If you keep the connections short (inside the PC itself) there's no need to buffer the signals. Last updated 1998/1/19

DTC3 v1.0 layout (PDF file)

Base FPGA circuit (not yet here)

The drivers

There are some simple linux drivers for current (2.2.9) kernel, which implement the MPU-401-like MIDI interface. Support for the NOHAU BDM emulator is included in the FPGA but not available outside of Windows; but there exist(ed?) a freeware BDM driver from Gunter Magin. Note that the last time the DTC2 driver was compiled was on kernel 2.1.128, so it probably has to be adjusted for 2.2/2.3.

Old schematics

I put these here too. Use them only as design examples, as I give no guarantee that they are still accurate and/or error-free.

The TWE. A double Eurocard, VME-like board with two Transputers and a DSP56000. It is still alive. Schematics made with OrCAD v4.

The DTC2. You will understand the reason for the name: 'DSP plus Transputer Card', or better in Italian 'Decisamente Troppo Complesso' ("way too complex"). Includes linux drivers, last updated for kernel 2.1.42 or similar, and OrCAD v4 schematics. To be fair, I never used more than 50% of the stuff I put in...

Some of my OrCAD libraries. You may find some useful components there. Source and v4 library format.

Some links

FPGA and HDL Resources on the Web
Links to FPGA WWW Servers
Free and Low-Cost Software for FPGAs, CPLDs, EPLD
Motorola Microcontroller Literature.
Chip directory
CAN: Controller Area Network
The Transputer archive
Ram's Transputer Home Page