I have a P1AM-100 that is losing its connection to its IO modules every 27 hours or so (not certain how consistent this timeframe is). Immediately prior to losing connection it outputs messages including "slow read" and "timeout", after which the P1.checkConnection() method returns 1 indicating a loss of connection to the first module. When the controller is reset, everything works normally again.

My setup consists of the P1AM-100 powered by an external power supply (PSRS-24-15) with a P1-08ND3 DI module and a P1-04TRS relay module. On the left I am using a P1AM-PROTO module to interface with a separate STM32-based board via pins 3, 4, 6 and 7 (simple ON/OFF signals) and via the second UART RX/TX pins.

A momentary button (with included button-pressed indicator in the form of a beep sound) is connected to one of the DI module inputs in series with the NC and common contacts of one of the relay module outputs. The code on the controller listens for a button press, then energizes the relay to disable the button (and its beep) while it interacts with the other board (~16 seconds) then de-energizes the relay to re-enable the button. I have included a 100nF capacitor across the DI module contacts to reduce noise on the button circuit as the physical button is located about 20' away. The controller code also includes debounce logic.

When the controller loses connection with the IO modules, it is still able to communicate with the STM32 board via serial and the other signal pins. The serial connection to the host PC also stays up.

I have run all of this through Claude AI for analysis, and it is suggesting there could be an I2C issue with the module communication, which might suggest electrical interference. Does that sound likely? Is there a way to get more diagnostic information from the modules? Could I have a faulty module?