greatscottgadgets / apollo

microcontroller-based FPGA / JTAG programmer
BSD 3-Clause "New" or "Revised" License
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FPGA not allowed to take over shared USB port by default #64

Closed mossmann closed 2 months ago

mossmann commented 2 months ago

This can result in Apollo claiming the CONTROL port on Cynthion instead of handing it off to the FPGA shortly after start-up.

Due to a quirk of Apollo's behavior, some gateware that starts requesting the CONTROL port early at start-up can gain control of the port, but this is unreliable due to unpredictable timing (presumably FPGA PLL start-up).