Maxim Integrated have started a PLC series called “Micro PLC” – the boards have a similar concept with STM32 at core and a backbone bus – except for that I don’t know much about them. It is a cute concept.
The system have several boards, the one above is quad channel analogue input. . I get the impression that the purpose is more to demonstrate Maxim technology than to create a PLC system thought, but who knows.