Upgrade MMDVM Duplex to Firmware v1.6.1

This guide covers the firmware upgrade process for the MMDVM Duplex hotspot (GPIO-based MMDVM_HS_Dual_Hat) to version 1.6.1 using the WPSD firmware binaries.

Prerequisites

• A working MMDVM Duplex hotspot (STM32-based, GPIO connected)
• The device must be running a Linux-based image (Pi-Star, WPSD, etc.)
• SSH access enabled on the hotspot
• If your board has a BOOT button, hold it while powering on the device. Only the power LED should illuminate — this puts the STM32 into DFU/ flash mode.

Step 1: SSH into the Hotspot

Connect to your hotspot via SSH:

ssh pi-star@pi-star.local

Default credentials:

Field	Value
Username	pi-star
Password	raspberry

Step 2: Download the Firmware

Change to the /tmp directory and download the v1.6.1 firmware binary:

cd /tmp
wget https://wpsd-swd.w0chp.net/WPSD-SWD/WPSD-Binaries/raw/branch/master/firmware/mmdvm_hs_dual_hat_fw.bin

You should see output similar to:

--2024-03-22 08:18:11--  https://wpsd-swd.w0chp.net/WPSD-SWD/WPSD-Binaries/...
Resolving wpsd-swd.w0chp.net... 74.208.60.144
Connecting to wpsd-swd.w0chp.net|74.208.60.144|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 55904 (55K) [application/octet-stream]
Saving to: 'mmdvm_hs_dual_hat_fw.bin'

mmdvm_hs_dual_hat_fw.bin  100%[===================>]  54.59K   238KB/s    in 0.2s

Step 3: Stop MMDVMHost and Flash

Stop the running MMDVMHost service, then flash the firmware using stm32flash:

sudo killall MMDVMHost
sudo stm32flash -R -w mmdvm_hs_dual_hat_fw.bin /dev/ttyAMA0

Expected flash output:

stm32flash 0.5

http://stm32flash.sourceforge.net/

Using Parser : Raw BINARY
Interface serial_posix: 57600 8E1
Version      : 0x22
Option 1     : 0x00
Option 2     : 0x00
Device ID    : 0x0410 (STM32F10xxx Medium-density)
- RAM        : Up to 20KiB  (512b reserved by bootloader)
- Flash      : Up to 128KiB (size first sector: 4x1024)
- Option RAM : 16b
- System RAM : 2KiB
Write to memory
Erasing memory
Wrote address 0x0800da60 (100.00%) Done.

Step 4: Verify the Upgrade

Run the modem detection tool to confirm the new firmware version:

sudo wpsd-detectmodem

Expected output:

Detected MMDVM_HS Port: /dev/ttyAMA0 (GPIO) Baud: 115200 Protocol: V1
         Modem Data: MMDVM_HS_Dual_Hat-v1.6.1 20231115_WPSD 14.7456MHz dual ADF7021 FW by CA6JAU, G4KLX, W0CHP. GitID #7e16099FF36066C3041383043023933

The key indicator is MMDVM_HS_Dual_Hat-v1.6.1 in the Modem Data line.

Quick Reference

Step	Command
SSH into hotspot	ssh pi-star@pi-star.local
Download firmware	wget [firmware URL]
Stop MMDVMHost	sudo killall MMDVMHost
Flash firmware	sudo stm32flash -R -w mmdvm_hs_dual_hat_fw.bin /dev/ttyAMA0
Verify version	sudo wpsd-detectmodem

Note: If your board does not have a BOOT button, simply power cycling the device and immediately running the flash command may also work. The -R flag tells stm32flash to reset the device after flashing.

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Authored on 2026-05-15 · Document Version: a1b2c3d · Last Revision: 2026-05-15