How to get Data from Rasperry to Arduino?

Question

Id like to get a simple integer from my pi over to my Arduino (live, so while both are running and with Minimum latency), but I cant use any Pins because im already using all of them because I use a sense hat. If I could get this simple int from like 1-10 over to my pi, I could tell my adruino what to do when int=1 so thats not a Problem, I just dont know how to get data over there.

• joan: I doubt the sense hat needs all the GPIO. Have you identified which are spare? Perhaps the UART is available? The question would then be how do I physically connect to those GPIO.
• jsotola: please be clear in what you are asking ... an int usually consists of 2 bytes and could be 4 bytes .... a value of 1 to 10 could be represented with a single byte

Answer 1

You can connect the Arduino to the Raspberry Pi with an USB cable. That gives you a serial connection. On the Raspberry side, you can use a library like pyserial. On the Arduino side, you can read bytes with

char x = Serial.read();

There's a tutorial at https://www.instructables.com/id/Interface-Python-and-Arduino-with-pySerial/