microsoft / uf2-samdx1

USB Mass Storage bootloader (based on UF2) for SAMD21 and SAMD51
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add wait to get line on potential (pullup/pulldown) without external pullup/down #114

Open xeno27 opened 6 months ago

xeno27 commented 6 months ago

Hi,

We got problems by removing an external resistor on our hold pin. Since there is a config for the internal pull up, we remove the physical one. This ends up in holding the board in the bootloader, because we load the pin config and directly check the pin status, but to get the pin on the pull-up state needs a few ms to get on the potential. As I see the pull-ups has a Resistance of 20-60kOhm.

Screenshot 2023-12-21 at 10 46 34

I have seen @dhalbert don't get the problem as they don't use the HOLD PIN ?

regards