New version of M17_ANL !

I plan to design a new version of M17_ANL.
Just because we are planning to support also analog FM capatibilites in our devices,
I want to use ADF7012 instead of Si4463(thank You Wojtek).
I’m thinking about using an STM32F103C8T6 microcontroller.
It has built-in USB-CDC converter, which I think is important, to make USB dongle smaller.
To make debugging easier, I want to place diodes - 4 (PWR, SYS, TX, RX) connected directly
by a resistor network to an STM32, and 2 connected to TX/RX switch.
What do You Think about it, do You have any ideas?
I will be grateful for the comments.

Is there a reason for creating a new version of M17_ANL with the ADF7021? MMDVM board has both the ADF and USB. It misses the analog FM part, but that’s still just an idea :slight_smile:

It’s just smaller, and easier to handle - better outside the lab :smiley:

I will never discourage anyone from stepping up and DOING something. :slight_smile: So, by all means, please do!

I do suggest that we keep the development platforms simple, at least in the early days. I don’t want to design anything that PREVENTS someone from building their own hardware, but for development purposes, it would probably be good if we were all using at least a similar architecture.

So, to that end, I encourage you to look at the architecture of the MMDVM system (which sounds really similar to what you’re proposing anyway) and do your best to limit the number of modifications to the software required to run on both systems.

Bonus of doing so: Your hardware benefits from all the support that MMDVM already has! It sounds like your goals are mostly a different physical form factor, not a critical electrical architecture change. There’s definitely space in this world for the MMDVM RPi hat, and an M17_ANL USB dongle, that both ultimately do the same/similar things.

Thank You for Your reply, without doubt, I plan similar architecture like MMDVM with integrated ADF7021,
with a little exception - small tiny DAC connected with STM32 by I2C - just to stream to STM32 audio by serial port, and transmit FM - by modulating VCOIN port of ADF7021.
What DAC do You propose? And what to You think about this?

Why not use an STM with internal DAC and ADC?

It seems that STM32F303CBT6 has everything we need…

Even better! :smiley:

First draft schematic of M17_ANL_v2 already on GitHub!

So is there an off-the-shelf MMDVM board that has the ADF7041 and the STM32F103C8T6 microcontroller already on it (just to have something to test against)?

–Konrad, WA4OSH/7

Yeah, an MMDVM HS hat.