Task: Test Integrated Circuits Using a TL866 Universal Programmer
Needed: Web browser, TL866 Universal Programmer, Compatible IC to Test
Time: 10-15 minutes
Disclosure: Note that as an eBay Partner Network Affiliate, I may earn from qualifying purchases.
Introduction
Troubleshooting a failed retrocomputer can often come down to determining whether any of the integrated circuits (ICs) have shorted and failed. There are several options for testing ICs. First, you can swap them out with known working chips to see if you can rescue the system. Second, you can probe the pins of the IC with an oscilloscope to see if the input and output signal look like they are supposed to. Finally, for some ICs, you can remove them and test them with a device that can read the chip and compare it to what is expected if working correctly (e.g. code if a ROM chip or logic tests). The most common device for this purpose is a TL866 Universal Programmer that has a zero-force insertion (ZIF) socket that makes it easy to insert the chip and test it. The current models of programmers include tests for thousands of different ICs. Note that they do not work for custom ICs such as the Commodore 64 SID chip or the Atari 800 ANTIC chip. Also note that you can use these to write EPROMS that can serve as replacement ROMs for many computers. I will cover that functionality in a separate post.
Instructions
These are widely available on Amazon for around $50 to $100 depending on the model. Most are Chinese made, and a popular brand is XGecu which is where I got mine from a few years ago. They come with the software (now called MiniPro) you need to interact with the programmer via a USB connection.
Using the programmer is quite simple. Plug in the unit via USB, approve the driver installation if needed, and launch the software that comes with the unit. Place the IC to test in the ZIF socket, select the type of IC you are testing, and hit the test button in the window that pops up. Below are images of the Xgpro software and from a passed and failed 7406 logic chip test.
Comments
This is a great addition to the troubleshooting suite of tools that you can use. It also doubles as an EPROM writer which can also be quite useful.
Here is the latest list of supported ICs that can be tested.
Note that for my older model it did not work with the latest version of the Xgpro software and there is not easy way to flash my unit from software. I am not sure if the newer models have this functionality. Fortunately, I still had access to the software that came with my unit.
This is cross-posted at retroprojects.org.