ATA Design
This page is about building an analog telephone adapter (ATA) which is wholly open-source and easily hack-able/adaptable to unusual use-cases (like payphones).
- MCU Selection
There needs to be a main processor, and this section runs through my thoughts as I consider the available options.
- Processor Capabilities
I'm making the decision up-front to ignore anything in the 8-bit or 16-bit category. While it may be possible to make it work, for a project I'm doing for fun, I don't want to spend my time hyper-optimizing just to get basic functionality working. This means I won't be looking at the Microchip PIC8/12/14/16/18, the Atmel Atmega line, or TI's MSP430. What it leaves on the table is: Arm (bunch of manufacturers), Microchip's dsPIC line, Risc-V, and the ESP32-variants using the Xtensa CPUs. There may be others, but this is all I'm considering to start, mostly because it's what I know!
- Connectivity
At a bare minimum, we'd like everything to have Ethernet. This is actually quite limiting! Things which still qualify:
- TI's ARM-R5 line and TMC129x line (Cortex-M4F)