mcumeter

The mcumeter crate contains a firmware written in Rust for the custom designed power meter board based upon a ST Microelectronics STM32F042 MCU and a Texas instruments INA260 power meter.

The hardware is also open source and can be found in this repository.

Building

To build the firmware, simply call cargo build --release and find the flashable binary in target/thumbv6m-none-eabi/release/mcumeter .

Flashing

OpenOCD

To use OpenOCD you will need to have OpenOCD installed and a separate SWD debugger available. The way how to use OpenOCD unfortunately depends on the debugging interface used. One of the easier way and OSS ways to flash is by getting a DAPLink interface (e.g. by buying a NXP FRDM board and populating the SWD header) and using the included script.

# openocd_program.sh target/thumbv6m-none-eabi/release/mcumeter

Via USB / dfu-util

To use this method you will to have cargo-binutils installed, this can be achieved by calling cargo install binutils outside of the software directory.

You will also need to have dfu-util installed.

Once those prerequisites are fulfilled you will need to convert the generated ELF binary into a raw binary file:

# cargo objcopy --release -- -O binary mcumeter.bin

To flash this file to the device you will need turn it into bootloader mode by shorting out the pins labelled BOOT and plugging the power. If the device is in DFU mode, dfu-util will tell you:

# dfu-util -l
dfu-util 0.9

Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2016 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to http://sourceforge.net/p/dfu-util/tickets/

Found DFU: [0483:df11] ver=2200, devnum=50, cfg=1, intf=0, path="20-11.2", alt=1, name="@Option Bytes  /0x1FFFF800/01*016 e", serial="FFFFFFFEFFFF"
Found DFU: [0483:df11] ver=2200, devnum=50, cfg=1, intf=0, path="20-11.2", alt=0, name="@Internal Flash  /0x08000000/032*0001Kg", serial="FFFFFFFEFFFF"

Once you've reached this stage you can flash the mcumeter.bin file using:

# dfu-util -a0 --dfuse-address 0x08000000 -D mcumeter.bin
dfu-util 0.9

Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2016 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to http://sourceforge.net/p/dfu-util/tickets/

dfu-util: Invalid DFU suffix signature
dfu-util: A valid DFU suffix will be required in a future dfu-util release!!!
Opening DFU capable USB device...
ID 0483:df11
Run-time device DFU version 011a
Claiming USB DFU Interface...
Setting Alternate Setting #0 ...
Determining device status: state = dfuIDLE, status = 0
dfuIDLE, continuing
DFU mode device DFU version 011a
Device returned transfer size 2048
DfuSe interface name: "Internal Flash  "
Downloading to address = 0x08000000, size = 13048
Download	[=========================] 100%        13048 bytes
Download done.
File downloaded successfully

License

0-clause BSD license.