blob: 30c75bccde4b20f7371d25ea8fcc651ad6fb2542 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
//https://tronixstuff.com/2011/08/26/arduino-mcp23017-tutorial/
//https://www.circuitbasics.com/how-to-use-an-mpc23017-port-expander-on-the-arduino/
//https://ww1.microchip.com/downloads/en/devicedoc/20001952c.pdf
#include <Wire.h>
byte BbyteVal=0;
byte AbyteVal=0;
byte chipAddr = 0x20;
byte GPIOA = 0x12; // PortA reg addr
byte GPIOB = 0x13; // PortB reg addr
byte IODIRA = 0x00; // PortA direction reg addr
byte IODIRB = 0x01; // PortB direction reg addr
void setup(){
Serial.begin(9600);
Wire.begin();
Wire.beginTransmission(chipAddr);
Wire.write(IODIRA); // IODIRA dir register
Wire.write(0xff); // set entire PORT A as output
Wire.endTransmission();
Wire.beginTransmission(chipAddr);
Wire.write(IODIRB); // IODIRB dir register
Wire.write(0xff); // set entire PORT B as input
Wire.endTransmission();
}
void loop(){
Wire.beginTransmission(chipAddr);
Wire.write(GPIOB); // read the inputs off PORT B
Wire.requestFrom(chipAddr, 1); // ask for 1 byte
BbyteVal = Wire.read(); // read it
Wire.endTransmission();
Serial.println(BbyteVal);
Wire.beginTransmission(chipAddr);
Wire.write(GPIOB); // read the inputs off PORT B
Wire.requestFrom(chipAddr, 1); // ask for 1 byte
AbyteVal = Wire.read(); // read it
Wire.endTransmission();
Serial.println(AbyteVal);
}
|
