Closed
Description
I'm trying to emulate an MCP23008 (I2C I/O Expander) and for that I need pin interrupts.
pulseio.PulseIn almost gives me what I need.
All I need to know is:
- has an interrupt happened since last time I checked
- what's the current pin value.
These are the problems I face with PulseIn:
- I don't get access to the very first edge, so I loose the first interrupt.
- If the pin is active on init I loose another edge due to idle_state
- In case of jitter, the pulse buffer is easily overrun. I will know that there was an interrupt, but I don't know the current pin value so I have to check with DigitalInOut. This means that I loose out on the next edge.
Adding an edge counter to PulseIn would solve these problems (counter will be cleared on read).
It would also be nice to have a PulseIn.pinvalue or something.
Or would it be better to just implement proper pin interrupts?