• FEMU 1.0.3 PCBs, FTDI EEPROM update, first MicroPython Example

    femtoduino05/21/2020 at 11:58 0 comments

    FEMU 1.0.3 has a revised RF layout and ground plane, along with more copper pour for the LDO footprint. I've also managed to break out both DAC pins. Currently testing the LDO at max throttle via the 2-layer prototype (larger, but same components).

    I've also figured out how to use ftdi_eeprom to adjust the behavior of the DTR and RST pins, and finally got the FT232XQ-R working nicely.

    If you're interested in making FEMU happens, buy me a coffee? ko-fi.com/femtoduino


  • Bluetooth UART working (with bodges)

    femtoduino10/16/2019 at 06:38 0 comments



    FEMU, with bodged RF inductor, appears to transmit just fine. There's some kind of issue going on with power supply, possibly related to grounding a few traces directly to the USB ground pin, and even more likely, due to the FTDI chip getting back powered at some point by the ESP32 chip... If I try any wireless stuff while plugged in to a computer, wireless stuff refuses to work. I modded a Bluetooth Arduino sketch I had (disabled all Serial comms), uploaded to the FEMU, and then powered the FEMU off a USB battery. Success! I was able to send a command and change the RGB color! Now...as to why two out of three RGB pins aren't PWMing... I'm not sure. There's more work to be done before I order another PCB revision. Stay tuned!

  • Working revision! (Mostly)

    femtoduino09/29/2019 at 18:58 0 comments

    At the very least, I've fixed the botched UART lines. I am able to flash MicroPython on to the FEMU. Unfortunately, I'm running into trouble trying to get REPL working with the latest esp-tool and MicroPython code base. I am going to troubleshoot it some more, but things seem to be manageable.