The M17 PHY layer is nearing completion!
The system is going to use 6.25k channels with 12.5k separation. SP5WWP has posted a proposal for the error correction scheme, which can be found in the Files section.
The schematic for the TR-9 portable radio is being actively worked on by DB9MAT and SP5WWP. The new version of the handheld, based around the ADF7021 RF front-end chip, will also include a 9DoF sensor, a 128x128 color TFT display (DEM128128ATMH-PW-N) and a Kenwood-style jack and Bluetooth for audio. The antenna connector is SMA (none of that RP-SMA rubbish). A GNSS module is also present, for APRS-compatible messaging.
M17 compatible radios will work with popular MMDVM modules. The TR-9 can also be used as an MMDVM compatible hotspot.
Programming (firmware flashing) of the TR-9 will be done via USB interface. Codeplug may be edited either by reading the SD card contents or via USB.
Upcoming tasks are:
- Preparing firmware for the TR-9 radio (STM32F7 microcontroller)
- Work on higher protocol layers