I received the TinyFPGA BX pre-production boards a few days ago and have been putting them through their paces. It's all good news so far. I found and fixed a few bugs in the tester firmware and updated the bootloader to use the controllable pull-up resistor and indicator LED.
I broke out all the boards from the panel and tested each one. Every single one passed. All 42 FPGA IOs, 16MHz clock, voltage regulators, and SPI flash are functional on all 20 boards. This means that the TinyFPGA BX project is GO!
This success is a big deal. If you've been following me on Twitter (@tinyfpga) or the logs on this project you know that the BX prototypes are testing a non-standard BGA footprint for the teeny tiny iCE40 FPGA. This footprint allows me to fan-out twice as many user IOs from the FPGA, but it does not follow the recommended guidelines for BGA packages. Getting 20 boards successfully manufactured and assembled gives me confidence that a full production run will have acceptable yield.
I have some plans to clean up the bootloader some more. There are a few bugs that I would like to fix as well as some features to make the "program, test, program, ..." flow more fluid for the user.
If you are interested in buying a TinyFPGA BX stay tuned, I will be launching a campaign on Crowd Supply in the coming weeks.