Watter flow meter Pulse counter and relay wireless with nodered


I make my order.

Thanks for all help. I know now more for my next order.


@rfontaine Hello Ryan.

I have buy 1-Channel General Purpose SPDT Relay Shield + 7 GPIO with IoT Interface.

Can you help me to interact with mcp23008 interrupt. My flow meter make 30 pulses per liter and the max rate is 500 liter per minute. So can generate 250 pulses per second.

In arduino i can register a interrupt because the hardware are direct connected but in this case I have to poll I2C.

I have read MCP23008 have a interrupt pin but I dont found information if this pin are connected to the ncd socket. I use pycom.

Thanks in advance.


@ryan or @Bhaskar Can help me with this question pls.

I need to know if MCP23008 INT pint are connected to some pin on pycom socket to detect interrupts and read the status of pins.

Thanks have nice day.


The schematic of 1-Channel General Purpose SPDT Relay Shield + 7 GPIO are public?


Hello anyone can help with this pls?


I have no experience with pycom, but have you tried using it to handle the Flow Meter’s Pulses, instead of the MCP ?



We don’t have a public schematic for that board but it’s pretty simple. We just connect SDA and SCL lines to the IOT socket and power the MCP23008 chip. The first GPIO is connected to the relay and the other 7 are exposed via screw terminals. The interrupt line from the MCP23008 is not(unfortunately) connected to the IOT socket.


Thanks for your answer @Travis

@rfontaine Yes I have think about that but how can I connect the pulses to the ncd board ?

I saw that only have 6 inputs connected to MCP


Not the NCD board, but connect Meter Pulse Output directly to an interrupt enabled pin on the WiPy3.
Again, I have no experience with Pycom/WiPy3. I could be way off-base.