Working with a factory (ESP flasher board)

This is an interesting one for some people I am sure.

We (A&A) do work with (UK) factories for some of our products, and it is interesting, but we get to visit the factory and see that we are happy with how they work, and we provide ATE kit. This is Automated Test Equipment. It will flash code on to the circuit board, and run self tests. In some cases they have a number of Ethernet leads to a test switch as well so it can self test all the Ethernet ports as part of the process.

But as you may know, I get lot of small dev boards from JLC in China. These are great, but they had a few issues with placement and soldering on the main ESP32 module lately.

The solution they propose is that I order some boards with a "functional test". This means I need to make an ATE for them, and send to China. They are going to do the first batch of boards with the functional test for no extra cost, which is nice, and I am going to try and get them to bag and label as well rather than their usual foam and bubblewrap annoyance. Fingers crossed that they can do that and that it is a sane price compared to my doing it. We will see.

The big reason for this is that they don't ship the failed boards, they debug them and fix them, so I don't end up with duff boards for which I don't have the equipment or eyesight to fix. The downside is this normally has a small extra cost.

But this has meant making a Flasher board. A device that can flash code on to one of my dev boards, and report clearly a self test pass or fail. The result is this. It is useful outside of the factory, maybe flashing Tasmota on Shelly boards, or just flashing boards I get in smaller quantities here. It is neater than using command line on my computer and has nice visual feedback on progress.

USB power, and a 6 pin RJ12 or USB-A connector. In this case the 6 pin RJ12 is to a TC2030 connector which plugs in to my boards.

This trick, and a lot of iterations in the code this week, has been to make it as idiot proof as possible.

It flashes from SD card, and can update image files over the internet automatically. It allows up to 10 different flash manifests by button press. It flashes multiple files in different places. It runs the code and waits for ATE: PASS or ATE: FAIL from the device. It provides a loop back link on the TC2030 even so my boards can do a loop back test on the final connection pins as part of their self test.

I have made a video to show the factory - I really hope this is as idiot proof as I hope.