I have tried to program several manufacturer's versions and over a dozen samples of the 2732A EPROM, and have concluded the GQ-4x4 is incapable of programming this device. I have tried using an external power supply (12VDC@2A), and I have tried stepping down the programming speed, but neither makes a difference.
I know for certain these 2732A EPROMs are not defective. I have been able to program them successfully with the ME2700 "Orphan EPROM Programmer" as well as the venerable Data I/O 29B with Unipak.
There are several older topics on programming the 2732A in this forum. None came to a conclusion with a positive outcome, and one concluded the problem was "counterfeit parts" - but this was merely an unsubstantiated guess.
There is no shame in the GQ-4x4 being unable to program the 2732A - this is a very old device that is not easy to program (just like the 2708 and 2716) and is simply beyond the physical ability of an inexpensive USB-based programmer to handle. No other USB-based programmer currently on the market is able to handle this device either. For example, although the 2732A is on the "supported list" for several models of Wellon programmer and the TL-866II Pro, in reality neither of these programmers is capable of handling the 2732A either.
It appears that people have had success programming the 2732A with older versions of the Willem programmer. Unfortunately it appears the GQ-4x4 has lost some of the capabilities of the original Willem design and along with it has lost the ability to program older EPROMs like the 2732A - therefore this device should be removed from its "supported device" list.
In theory the 2732A "should be" supported because - yes - the GQ-4x4 is able to generate a 21V programming pulse. However, based on my experience and reports on other web sites the GQ-4X4 is not consistently able to program these devices. If you are really lucky, it will work for a select samples of Intel or ST 2732A chips. Unfortunately most of the time it will not, possibly because either the GQ-4x4 programming algorithm for the 2732A is marginal and/or the ability of the power supply to supply 21V of sufficient current for the required length of the programming pulse is marginal.
2732A EPROM incorrectly listed as "supported"
Posted - 02/28/2025 : 21:54:29
