surely I can make my own EPROM programmer. Once I had it running on mains power again, it burnt the EPROM OK (fortunately I wanted to burn to the top 32K, so the wasted 00 byte at the bottom was not that irritating).
Doh!), and I guess the voltage levels of the parallel port (which are probably marginal to start with) are much worse when running on battery … or at least that was my theory. It was fine.Įventually I worked out that the Thinkpad was running on battery (I had plugged it in and forgotten to turn it on. My Willem had blown up its 74HC04 some time back, so I checked the replacement one I put in. Now ensues an hour or two of trying to figure out what was wrong. I tried to burn a 32K image … and nope … the Willem decided to burn a solitary ’00’ byte to the first byte in the EPROM … and do nothing more. I got the Willem out, plugged it into my trusty old Thinkpad T42 (it has a parallel port!). Recently I was trying to burn a 27C512 to put into my C64C. When I bought it, it seemed like the cheapest way of programming the special 16bit EPROMs used in the Amigas. Other times you tear your hair out trying to figure out whats wrong with it. I’ve had a lot of weird problems with the Willem. I bought it when I was trying to burn Amiga Kickstarts, but I’ve used it for burning 27C256’s and 27C512’s as well. I'm going to get ahold of that programmer later on to see if maybe we can do a little hack to make it work.I have a Willem parallel EPROM programmer (or clone). I'm not sure how bad it can be to stray from those parameters, but Rick sent me back a batch of chips that failed in programming, and I'm pretty sure it must have to do with his old programmer that was delivering 25 millisecond CE pulses with up to 3 repeats, with Vdd=6.0 volts and Vcc=12.5 volts. The programming specs suggest CE pulses of 100 microseconds +/- 5 microseconds at up to 10 repeats, and Vcc=6.5 volts and Vpp=13.0 volts, both +/-0.25 volts. Maybe he'll have to shell out the $300 or $400, since he wants to continue with this. But I know I'm not going to have time to build it, and I'm sure Rick wants a plug and play that he can hook up to his PC. I like the idea of a Prop based programmer. At the time I could spin BC, DE and HL pretty fluently, a hazy hazy memory now. The T102 was also at the heart of my original OWL data loggers. And I also manufactured RAM expansions called the "extram" and the "XR4" and the RAMpak, and provided operating system extensions to used the additional banked memory. It used a special circuit board material called "bendflex" that has since been discontinued. We use a bridge from the programmer to an SOIC clamp to program the chip, and the large plated through holes on the edge of the circuit board are cut through to expose 28 half-moon contacts that press down into the option socket.īack in its heyday, I made a different design of option ROM adapter called ROMBO that I sold a lot of through the magazines. Not only is it a proprietary deep socket, but in their great wisdom Rat Shack switched the pin connections so that it doesn't correspond to the standard 27C256. I provide Rick with the OTP soic eproms mounted on a carrier that fits into the option ROM socket.
Yes, amazing, there are still a lot of them out there running printing presses and laundromats and the in the cruisers of small police departments in the desks of a certain breed of news reporters and in classrooms. He has an ongoing evening business in buying and selling Tandy 100, 102 and 200s, and in providing add-on ROMs.
This programmer is for my friend, Rick Hanson, who operates Club 100.