chrissbarr
commented
2 years ago Hi @mateusz-kusmierz ,
I don't have a Teensy 4.1 on hand, so can't test this properly. I've put together an example I believe should work (#16), which is as below:
#include <Arduino.h>
#include "i2c_driver_wire.h"
#include "PCAL9535A.h"
/**
* This example uses the multiple I2C interfaces on the Teensy 4.1 board.
* Uses the teensy4_i2c library here:
* https://github.com/Richard-Gemmell/teensy4_i2c
*
* (I2C peripherals are exposed as Wire, Wire1, and Wire2)
*/
PCAL9535A::PCAL9535A<TwoWire> gpio1(Wire);
PCAL9535A::PCAL9535A<TwoWire> gpio2(Wire1);
PCAL9535A::PCAL9535A<TwoWire> gpio3(Wire2);
void printAllGPIO(PCAL9535A::PCAL9535A<TwoWire>& gpio) {
int state = gpio.readGPIO16();
for (int i = 0; i < 16; i++) {
bool b = state & (1 << 15);
Serial.print(b);
state = state << 1;
}
Serial.println();
}
void setup() {
gpio1.begin(PCAL9535A::HardwareAddress::A000); // 0x20 - Pins = 000
gpio2.begin(PCAL9535A::HardwareAddress::A000);
gpio3.begin(PCAL9535A::HardwareAddress::A000);
Serial.begin(9600);
}
void loop() {
Serial.println("");
Serial.print("GPIO1: "); printAllGPIO(gpio1);
Serial.print("GPIO2: "); printAllGPIO(gpio2);
Serial.print("GPIO3: "); printAllGPIO(gpio3);
delay(100);
}This is using the Teensy 4.1 I2C Library here: https://github.com/Richard-Gemmell/teensy4_i2c.git
I am unsure if you are using that library or if there are alternatives. Let me know if there's something else you're using and I can try that too.
The above example builds for me and seems like it should work. If you do give it a go, can you let me know if it works for you?
Hello. How do I use this library on other than default I2C interface? I'm using teensy 4.1 board that has multiple I2C interfaces, but I don't know how to initialize this library on other I2C interfaces.