Reviving old prototypes and code
I spent a few years during Covid and the ensuing chip crisis building TF1260 boards and more recently a bunch of CTPCI boards. This helped improve my surface mount soldering skills quite a lot, though I have a lot more to learn still.
Anyway armed with this knowledge I decided to repair my old prototype boards. A few years ago I ripped up the pads and traces around the flash chip (which initializes the FPGA) on one of them when trying to change the chip to a more compatible flash chip. I was able now to use tiny thin copper wire and solder mask to repair the pads and traces. I was also able to fix the HDMI port on one of them which I never managed to solder at the time. Its nice to see the time invested in learning and practicing this has paid off.
I then found my latest code which was v37 + internal pokeymax + two different scalers does not fit into the small FPGA at all any more. The last I'd checked it fitted but would not work due to some Quartus bug. Anyway I decided for now to ditch these changes, go back to v37 and just put in fixes I've found in the meantime. Getting there with that.
One thing I found out that may interest you all is that I'd missed decoupling on the SD card slot. So this is why it sometimes crashes when hotplugging sd cards. I added a 220nF and then a 4.7uF over the 3.3v/GND at the connector and it seems much better. So an easy fix for anyone suffering from this.
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Added by foft 9 months ago
Actually best make it higher still for that cap, it suggests 45uF here: https://resources.altium.com/p/how-to-design-microsd-power-circuits-without-destabilizing-on-board-voltage-supply