Spent a couple of days adding a LED display to my Time Code generator, added a display driver to the software. Then it went pear shaped. I must remember to make sure I’m programming the micro with the correct hex file, not one from another project. Shit happens.

I put a cheap temperature compensated 12MHz crystal oscillator on the slate instead of the normal 50cent 12MHz crystal, it measured about 1PPM fast, not bad, as my workshop is warm, about 28 C this time of year.

The time code is set up for 25fps, and the camera is in frame mode not PAL. . Here’s a pretty dreadful workbench video, the firewire died on my normal camera:

I ran out of patience, and stopped videoing at 6 hours. It looks pretty OK to me with no obvious drift.

Next thing to do is to make a small environment chamber with a Peltier heat pump, so I can drop the temperature of the slate, to below 0C, and see how it drifts. I went dumpster diving and got a nice thick sheet of polystyrene that should do nicely for the thermal insulation.

The PCB firm I use is on holiday until 1st of September, I really want to get my hands on the next set of boards.

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