add possibility to pass in a Wire instance

[SunboX]

This adds the possibility to pass in a Wire instance to be able to configure the clock speed / frequency and also the used IO pins.

[ladyada]

looks good! what hardware did you test with?

[SunboX]

Thanks! I tested with an ESP32 Dev Kit from AZ-Delivery and an MCP23017 Expansion Board from Waveshare

[ladyada]

do you have an AVR board like UNO to check with?

[SunboX]

I have to look into my box, but I might have none.

[ladyada]

ok please do :) that will help a lot!

[SunboX]

Ok, found one in one of my boxes. Will test it tomorrow.

[ladyada]

perfect :)

[SunboX]

Ok, I tested it using an Arduino Uno and set the clock speed to 400khz. Here's my test code:

#include <Wire.h>
#include "Adafruit_MCP23017.h"

Adafruit_MCP23017 mcp;

void setup() {

    Wire.setClock(400000); // set frequency to 400khz

    mcp.begin(7, &Wire);

    mcp.pinMode(5, OUTPUT);
    mcp.digitalWrite(5, HIGH);
}

void loop() {

    delay(5000);

    mcp.digitalWrite(5, LOW);

    delay(5000);

    mcp.digitalWrite(5, HIGH);
}

And here's a video showing the test:
https://youtu.be/4aTDRAySRF4

Sadly I have no oscilloscope, so I could not validate if it runs @ 400khz.

[ladyada]

sounds good, thanks!

[SunboX]

Thanks a lot!