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4-bit eMMC slot colliding with JTAG

Posted: Tue Sep 15, 2020 8:46 am
by Xavi92
According to the documentation, only two pin configurations are available for the SDMMC host peripheral. We want to replace an already working SD card interfaced via SPI by eMMC storage, but the 4-bit slot available on the ESP32 is connected to the same pins as the JTAG inteface. (GPIO 12, 13, 14 and 15).

Does this mean it is not possible to interface eMMC storage with minimum number of pins without sacrificing JTAG?

Re: 4-bit eMMC slot colliding with JTAG

Posted: Fri Sep 18, 2020 6:34 am
by Xavi92
Does anyone know any solution to this issue?
Thank you very much.

Re: 4-bit eMMC slot colliding with JTAG

Posted: Sat Sep 19, 2020 8:54 pm
by WiFive

Re: 4-bit eMMC slot colliding with JTAG

Posted: Tue Sep 22, 2020 6:22 am
by Xavi92
Thank you for your reply. Then I assume there is no (clear) solution to this so source-level debugging needs to be sacrificed if SDMMC is used on the JTAG pins.