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Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
@Jscott
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Remember that our goal was to have an Espruino board with more RAM. In summary, we mod an Espruino board to replace the MCU, modify ESPRUINOBOARD.py to specify the correct values, build the firmware, then install it via the serial bootloader.
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a. We have the STM32F103RFT6 chip with 96kB RAM on the Espruino board. This results in a board with no firmware.
b. We had to remove the bluetooth module to allow our TTL interface to work on USART1 A9/A10.
c. We setup the board with pins and jumpers so that we can enable the serial bootloader.
d. I put the board into bootloader mode and used the ST Flash Loader Demonstrator via VirtualBox to write the original firmware version 1v58; just to ensure that everything worked as before. I had better results with the Demonstrator and not with the stm32loader.py script.
e. One caveat was that afterwards, I had to use the USB-TTL setup to connect to the Web IDE, then issue a reset();. At this point, everything started to work normally and I could connect via the onboard USB port to run programs and flash firmware. Basically, the blue and red LEDs stayed dimly lit and the board remained "stuck" until I connected the Web IDE via the chip's USART interface and entered a reset(); command.
f. I pulled the 'cutting edge' latest firmware from Github, and modified ESPRUINOBOARD.py, along with a Makefile tweak to ensure that everything builds on my Vagrant/VirtualBox/linux instance. (Thx Forums for that setup!)
g. With my new binary, I used the stm32loader.py script to flash the modded firmware that has the new memory settings. Sadly, I get Verification FAILED after the writes. I can easily restore version 1v58 and it works; but the modded firmware won't install. Any ideas why the verification is failing? Do the nightly builds typically install fine; or do they just build?
Any help is appreciated. We're so close!!!
Thx!