A Low-Cost ROM Programmer With An AI Twist

March 23, 2024 by Dan Maloney 11 Comments

There are 0x10 ways to look at ROM programmers: they’re either relatively low-cost tools that let you quickly get about the business of programming vintage ROMs and get back to your retrocomputing activities, or they’re egregiously overpriced on a per-use basis. [Anders Nielsen] seems to land in the latter camp, firmly enough that he not only designed a dedicated ROM programmer for his 65uino ecosystem, but also suffered the indignities of enlisting ChatGPT to “help” him program the thing.

We’ll explain. [Anders]’ 65uino project has been going on for a while, with low-cost ROM programming only the latest effort. To his way of thinking, a $60 or $70 programmer might just be a significant barrier to those trying to break into retrocomputing, and besides, he seems to be more about the journey than the destination. He recently tackled the problem of generating the right programming voltages; here he turns his attention to putting that to work programming vintage ROMs like the W27C512.

Doing so with a 6502-based Arduino-compatible microcontroller requires some silicon calisthenics, including a trio of shift registers to do the addressing using a minimum of GPIO. As for the ChatGPT part, [Anders] thought asking the chatbot to help write some of the code would be a great way to increase his productivity. We thought so too, at least once, and like us, [Anders] concluded that while perhaps helpful in a broad sense, the amount of work you put into checking a chatbot’s work probably exceeds the work saved. But no matter, because in the end the code and the hardware came together to create a prototype ROM programmer for only about $10 worth of parts.

True, the resulting circuit is a bit complex, at least on a breadboard. It should clean up nicely for an eventual PCB version, though, one that plugs right into the 65uino board or even other microcontrollers. Either way, it could make creating custom ROMs for the 65uino a little more accessible.

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Thinkpad T25 Gets Less Retro With Hardware Swap

February 23, 2019 by Tom Nardi 14 Comments

For many, the Thinkpad T25 was something of a dream come true. Celebrating the 25th anniversary of the venerable business-oriented laptop that hackers love so much, it featured a design inspired by “retro” Thinkpads of yore, but with modern hardware inside. Unfortunately, as it was more fan service than a serious revitalization of classic Thinkpad design, the T25 was only ever available in a single hardware configuration.

[kitsunyan] liked the look and feel of the T25, but in 2019 was already feeling a bit let down by the hardware. The screen wasn’t up to snuff, and while the CPU is an i7, it only has dual cores. To make sure the T25 is still viable down the road, it seemed the only option was to try to transplant the hardware from one of the current Thinkpad models into the anniversary chassis. It certainly wasn’t easy, but given the fact that the T25 was more of a redress than a completely new product to begin with, everything came together a lot better than you might expect.

To help put things into perspective, the T25 is basically a modified version of the T470. Last year, Lenovo replaced the T470 with the new T480 that has just the sort of hardware improvements that [kitsunyan] wanted. The T480 was more of a refresh than a complete revamp, so the actual chassis of the machine didn’t change much compared with its predecessor. That being the case, it seemed like it should be possible to transplant the newer T480 components into the T470 derived T25. Got all that straight?

[kitsunyan] was able to put this theory to the test when the opportunity to connect a T25 keyboard to the newer T480 presented itself. Since the 7-row keyboard on the anniversary edition was one of its biggest selling points, seeing if it would work on another machine was kind of a big deal. It didn’t fit physically, and some of the keys didn’t work as expected, but it at least had the same connector and didn’t let out the magic smoke. It represented the first tiny step of a much larger journey.

In the end, it took a lot of trimming, gluing, hacking, and fiddling to get all the new hardware from the T480 to fit into the T25. But if you’re brave enough, the process has been detailed exquisitely by [kitsunyan]. Not only are the part numbers listed for everything you need to order, but there’s plenty of pictures to help illustrate the modifications that need to be made to all the clips, brackets, and assorted widgets that go into a modern laptop.

While we’re very impressed by this project, we can’t say it comes as a complete surprise. We’re well aware of the incredible lengths Thinkpad aficionados will go to keep their machines running into the 21st century. But don’t just take our word for it, you too can join the ranks of the Thinkpad elite.

[Thanks to Pierre for the tip.]