The IO boards arrived about a week after putting the order in. The front of one of the boards: And the back: Interestingly I received two extra boards. An extra usable board and another one. The other board had been used for some kind of testing by the manufacturer as it had a piece cut out of it. The box… Read more »
The IO board for the MINI000, outlined in the last post, has been designed and the PCB, pending some final checks, will soon be ordered from the allpcb.com PCB house in China. A few ICs have not made it. I’d hoped to include a MC68230 (PDF) but as they are available only in DIP48, there’s just not enough room for… Read more »
This blog post does not document what I’ve done in my hobbies, except for some small projects, but rather what I plan to work on next. Before getting to that though, I should finish my description of the progress I’ve made with the VGA controller. I have attached the EPF10K10 (PDF) FPGA to the 68000 CPU bus, and have had… Read more »
The machine-code monitor for my MINI000 68000 SBC is coming along nicely. It’s been great fun and an excellent introduction to writing 68000 assembly. Command processing consists of the following steps: Read a line of text from the serial port. Parse the line into command and argument portions. Locate the command from the set available. This will result in a… Read more »
There are more than a few different choices of C library for running on small systems. Some candidate C libraries for the MINI000 board include: Newlib is an extremely popular choice for small systems. It is relatively complete. Not quite complete enough for a modern desktop Unix system, but almost. It specifically targets bare-bones (AKA freestanding) 68K systems, and allows… Read more »
I’ve been focusing back on the 68000 SBC for the last few weeks. I’m my previous post I mentioned that I’d had no problems with the MAX232 (PDF) portion of the board. As it turned out, this was not strictly true. It seemed that after the board was powered on for a few hours the XR88C681 (PDF) DUART would send… Read more »
The MPCNC is now ready to be used in anger. It took longer then I’d have liked but it’s all ready for serious cutting, albeit in wood: Making the spoil-board up was a bit of a mission, mostly because I’m completely new to this kind of thing. I started with a 600mm by 1220mm by 18mm thick piece of MDF…. Read more »
Five MINI000 boards arrived just after Christmas. Annoyingly I got stung for the import duty, but fair enough. They were still very cheap! The quality looks fantastic, though its hard to tell from a camera-phone shot: The following was done over the course of a few weeks. Unlike the MAXI09 board bringup, I took my time and found I enjoyed… Read more »
I have decided to be a little brave and have opted to build a 68000 SBC instead of one based off a 68008. Specification wise it is similar to the 68020 design: 68000 clocked at 16MHz 1MB static RAM (2 x AS6C4008 (PDF)) 64KB EEPROM (2 x AT28C256 (PDF)) DUART (XR88C681 or, in its place, a SC2681 (PDF))) Expansion connector… Read more »
After writing about building a 68020 computer I feel slightly silly for going back on my word: I have built up a 68008-based computer on breadboard. For one thing going right to a 68020 felt a bit like I’d be missing out; the pleasure is in exploring not the end result. I’d have left out on the other MPUs in… Read more »