for RPM the CPU has to count every input signal, measure its frequency and sum it up for the result.
at the same time it also has to receive wifi.
both are timecritical.
the wifi has higher priority, so there will be some events on the RPM signal getting lost.
better use an little ESP32 chip to do all the RPM input as an helper device. often little microcontrollers have an internal counter chip integrated. this will do most of the worktask. there are some good libraries to send the data to signalk. i often use SensESP for this stuff.
ym2c - holger
at the same time it also has to receive wifi.
both are timecritical.
the wifi has higher priority, so there will be some events on the RPM signal getting lost.
better use an little ESP32 chip to do all the RPM input as an helper device. often little microcontrollers have an internal counter chip integrated. this will do most of the worktask. there are some good libraries to send the data to signalk. i often use SensESP for this stuff.
ym2c - holger