The port of the MMDVM code to the STM32F4 series has taken a major leap forward
As per Jim's email to the MMDVM Yahoo group late last night
Does that guy ever sleep :-)
All the source code is already waiting on github. Andy posted the modified Standard Peripheral Drivers in the Files section of the MMDVM Yahoo group. I just posted a text document detailing how to build the code and program the boards.
To start we have support for the STM32F407 Discovery board and the STM32F446 Nucleo board.
I'm attaching a picture of Andy's setup. He's got it working well on DMR. You can also see that he's included the TCXO board for a more accurate clock. I've been doing my testing on DStar.
The instructions include details for building under Windows, OSX and Linux using gcc. There is also limited support for building the code under CooCox (Win32).