The following instructions describe how to update an STM32-DVM-MTR2K MMDVM modem for use in a Motorola MTR2K with an OrangePi NanoPi. Doing this update will add the M17 Digital Voice mode to the MMDVM modem.
It is important to know that out-of-the-box, the Repeater Builder STM32-DVM-MTR2K ships with:
It is also important to know a functioning MMDVM M17 system consists of at least these three elements:
As shipped, the SD card in the NanoPi runs an older version of the Pi-Star software. It is not possible to run this version of Pi-Star with the updated version (v1.6.0) of the MMDVM firmware. Work is being done to hopefully rectify this, or in the meantime, WPSD / W0CHP Pi-Star Dash can be used.
Attach the NanoPi to your network via an Ethernet cable.
Apply power to the DC converter on the modem board. The DC converter is the blue board on the modem board, and has four pins extending from the top. Be sure to note the labeled polarity and which pins are labeled as input
(IN+ / IN-). The DC converter will take voltages from 7v-15v. A standard 14.1v power supply such as the Powerwerx SS-30DV will work.
Allow the NanoPi to boot into Pi-Star. This may take several minutes. If this is a brand new (unconfigured) Pi-Star installation, configuration of Pi-Star is not needed at this time.
Using an SSH client, log into Pi-Star running on the NanoPi.
Update the operating system and get the needed tools for retrieving the sources and compiling them.
sudo apt update
sudo apt install git gcc-arm-none-eabi gdb-multiarch libstdc++-arm-none-eabi-newlib libnewlib-arm-none-eabi
cd ~ git clone https://git.code.sf.net/p/stm32flash/code stm32flash cd stm32flash make sudo make install
The newest firmware can always be found on GitHub.
cd ~ git clone https://github.com/g4klx/MMDVM.git cd MMDVM/ git submodule init git submodule update
You will need to edit Config.h with the appropriate settings for the NanoPi and the modem:
The only configuration option that needs to be changed is the UART speed used for communication between the NanoPi and the modem. All other configuration options can remain unchanged. Comment out
#define SERIAL_SPEED 460800 and uncomment
#define SERIAL_SPEED 500000
// #define SERIAL_SPEED 460800 // Only works on newer boards like fast M4, M7, Teensy 3.x. External FM should work with this #define SERIAL_SPEED 500000 // Used with newer boards and Armbian on AllWinner SOCs (H2, H3) that do not support 460800
Save the file and exit.
Compile the firmware.
If everything compiles as expected, you are ready to flash.
STOP the running Pi-Star services. Not doing so will block stm32flash from being able to access the UART.
sudo pistar-watchdog.service stop sudo systemctl stop mmdvmhost.timer sudo systemctl stop mmdvmhost.service
To flash the new firmware to the board, the board must be placed in “bootloader” mode. To enable this:
LOAD) on the modem board
When the board is successfully in bootloader mode, several of the LEDs will be steadily lit, and none should be blinking at this time.
You can now run the command to flash the firmware to the board:
sudo make deploy-eda446
This process can take a few minutes to complete. While the board is being flashed, you may see the ACT LED blinking. This is normal. The board will be reset upon completion of the flashing process.
Due to the way that the Makefile for the firmware is written, the flashing process may try to run twice, throwing an error after the board restarts at the end of the first flashing process. This error can be ignored.
After the board restarts, the HB LED should be flashing slowly. You can now restart the NanoPi.
Updating Pi-Star to include the latest binaries for use with MMDVM firmware v1.6.0+ is outside the scope of this document. However, you can update Pi-Star with W0CHP Pi-Star Dash from the installed version of Pi-Star that ships with the SD card on the STM32-DVM-MTR2K.
You must first update the Pi-Star install on the SD card to at least v4.1.6 before installing W0CHP Pi-Star Dash. You may have to run the Pi-Star update a few times.
Follow the instructions found at https://w0chp.net/w0chp-pistar-dash/ to update Pi-Star to the latest binaries and dashboard configuration.
When configuring W0CHP Pi-Star Dash to use the updated STM32-DVM-MTR2K, use the modem option
STM32-DVM-MTR2k (GPIO v3+ 500000 baud). All other configuration options can be set as normally on Pi-Star.