Re: Port to M5Stamp-C3U
That's sweet! I am updating an existing design from ESP32-WROOM-32U-N4/platformio to ESP32-S3-WROOM-1U-N16/nuttx so I got this new S3 board - https://www.mouser.com/ProductDetail/356-ESP32S3DEVKTM1N8 I will have to try it out! Thank you! On Fri, Dec 9, 2022 at 6:17 AM Sebastien Lorquet wrote: > (Note that I did write "use" not port :p) > > I got it working very fast by reading all the provided docs! This was > very well made this time, the level of support for this chip is very pro. > > I could even recompile the required second stage bootloader from source. > > It's fun that this bootloader requires a riscv32 toolchain whereas nuttx > is compiled with another riscv64 toolchain! > > All that would remain to do is write a board config for the name > "m5stamp-c3u" instead of "esp32c3-devkit" but I'm too lazy for that, > sorry :p > > Sebastien > > Le 09/12/2022 à 13:14, Alan C. Assis a écrit : > > Hi Sebastien, > > > > On 12/9/22, Sebastien Lorquet wrote: > >> Hi, > >> > >> As an introduction to the RISCV, I would like to use NuttX on my M5stamp > >> C3U, which I can get for 8 dollars at a local store. > >> > >> https://docs.m5stack.com/en/core/stamp_c3u > >> > > This M5stamp C3U uses that ESP32-C3 that is already completely > > supported on NuttX. > > > > So, if your plan was to do a port, you arrived too late in the party :-D > > > >> The module does not use a usb serial chip but direct USB connection > >> (there is a schematic in the bottom of the page). > >> > > The USB serial on ESP32-C3 is already support on NuttX mainline too. > > > >> I wonder how it works: Is serial on USB supported by an internal > >> bootloader or does this require firmware support that will disappear > >> after I flash this board for the first time? > >> > > It doesn't require a firmware and normally will not require a host > > driver because it is a generic USB CDC Serial internal. > > > > Espressif create a nice thing that all MCU should have: a USB Serial / > > JTAG internally integrated in the chip. > > > > So, you don't need an external programmer neither an external > > USB/Serial. Just a USB cable and you can program the chip and get a > > console interface. > > > > You can get more info about it reading the "USB Serial/JTAG > > Controller" chapter of the ESP32-C3 TRM. > > > > BR, > > > > Alan >
Re: Port to M5Stamp-C3U
Hi Sebastien, On 12/9/22, Sebastien Lorquet wrote: > Hi, > > As an introduction to the RISCV, I would like to use NuttX on my M5stamp > C3U, which I can get for 8 dollars at a local store. > > https://docs.m5stack.com/en/core/stamp_c3u > This M5stamp C3U uses that ESP32-C3 that is already completely supported on NuttX. So, if your plan was to do a port, you arrived too late in the party :-D > The module does not use a usb serial chip but direct USB connection > (there is a schematic in the bottom of the page). > The USB serial on ESP32-C3 is already support on NuttX mainline too. > I wonder how it works: Is serial on USB supported by an internal > bootloader or does this require firmware support that will disappear > after I flash this board for the first time? > It doesn't require a firmware and normally will not require a host driver because it is a generic USB CDC Serial internal. Espressif create a nice thing that all MCU should have: a USB Serial / JTAG internally integrated in the chip. So, you don't need an external programmer neither an external USB/Serial. Just a USB cable and you can program the chip and get a console interface. You can get more info about it reading the "USB Serial/JTAG Controller" chapter of the ESP32-C3 TRM. BR, Alan
Re: Port to M5Stamp-C3U
Hi, OK I got the bootloading part figured out (eg, it shoud work because the esp32c3 has a serial bootloader mode in ROM that should support usb CDC, and I see a serial port by pushing the GPIO9 button while plugging it in), I will try to use my board as a esp32c3 devkit for now, it shoud be similar. (later) So the esp32c3-devkit:usbconsole configuration works on the m5stamp-c3u. nsh> uname -a NuttX 10.1.0-RC1 512be93c36 Dec 9 2022 12:32:21 risc-v esp32c3-devkit Nice. Sebastien Le 09/12/2022 à 11:21, Sebastien Lorquet a écrit : Hi, As an introduction to the RISCV, I would like to use NuttX on my M5stamp C3U, which I can get for 8 dollars at a local store. https://docs.m5stack.com/en/core/stamp_c3u The module does not use a usb serial chip but direct USB connection (there is a schematic in the bottom of the page). I wonder how it works: Is serial on USB supported by an internal bootloader or does this require firmware support that will disappear after I flash this board for the first time? I ask this dumb question here because I know there are ESP32 people on this list. Thanks for the help, Sebastien
