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Interrupted

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It has been a while. Full-time paid employment means I have enough cash to finish this but limits the time I can spend finishing it. The current state of play it that I have added some SMDs to get in some practice with those. One of the SMDs is a frequency multiplier so that with the original crystal to drive the video I can vary the CPU speed from the 3.278MHz of the original ACE up to 19.668MHz and perhaps beyond. I've also made some modifications to make the KIO optional and enable full ACE compatibility. The KIOs are very difficult to get hold of and with Z84C15 and Z182 available these seem like the best CPU to be going forward. The fastest CPU I have is 20MHz and while I had to up the speed of the RAM, everything else seem happy on the CPU side. The Video was less happy, but I am not 100% convinced that was a speed problem. The multiplier I'm using on this board is a Renesas 512MLF , which is pin compatible with the On Semiconductor NB3N502DR2G , though the multiplicat
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KIO IC

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I finally got a version up with the KIO working. This is not using the ACE ROM yet but a rather hacked to gether bit of test code. The CTC is being used to generate the 50Hz interupt and drive the 4 flashing charters on the right and the real time clock. The PIO is flahing the LED, whilst the SIO is handling the comms to the PC. There is still a bit of instability in the comms resulting in the MSB being high and the off spurious extra interupt. On the circuit board is the odd patch wire but I have ordered boards with these patches built in. I'm not sure how to set up the comms. I think I can interface directly to a KeyBoard with no extra hardware but I migt putin an STM8 and communiate with that and let that do the grunt work for the kayboard interface.  I will up load the testrom source soon, just as soon as I can face git hub.    
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Hot

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  I've been playing ISE Design Suite and finally received my programmer and xc9500 test card. The programmer is found by ISE running in a virtual box on Windows 11. So that's good however the IC gets very hot very quickly when powered up. Is this normal? 
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CPLDs & Xilinx

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One of the problems with GALs is the development tools which are way out of date. Though preparing the files by hand doesn't seem to be too difficult. The other problem is the relatively small number of pins. The next step up is  Complex Programmable Logic Devices ; CPLDs come in a far larger variety and there or some development kits available for the older legacy designs.    Some of Microchips' offerings, such as the ATF1504AS, can be programmed using WinCUPL like GALS. They also offer a full system such as ATF15XX-DK3-U that can be bought from the likes of Mouser at reasonable prices, though it is quite a high value for reasonable. Lattice & Intel also do similar things.   Having done a bit of research and found that Xilinx has released their old Integrated Synthesis Environment; ISE system, which does schematic capture. I decided to check out that route. Schematic capture is not used that much, but, I find it very useful when translating the logic designed in KiCAD and
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