Chuck Swiger / Mbed OS FTHRChirpChangeAddr

Change i2c address in the Chirp! sensor

main.cpp@0:0b271f6ca9be, 2018-07-31 (annotated)

Committer:
cswiger
Date:
Tue Jul 31 18:17:05 2018 +0000
Revision:
0:0b271f6ca9be
Change Chirp! i2c address

Who changed what in which revision?

UserRevisionLine numberNew contents of line
cswiger 0:0b271f6ca9be 1 #include "mbed.h"
cswiger 0:0b271f6ca9be 2
cswiger 0:0b271f6ca9be 3 // Change Chirp! Address - default starts with 0x20
cswiger 0:0b271f6ca9be 4
cswiger 0:0b271f6ca9be 5 I2C i2c(P3_4, P3_5);
cswiger 0:0b271f6ca9be 6
cswiger 0:0b271f6ca9be 7 int addr = 0x20;
cswiger 0:0b271f6ca9be 8 int addr8 = addr << 1;
cswiger 0:0b271f6ca9be 9
cswiger 0:0b271f6ca9be 10 int main() {
cswiger 0:0b271f6ca9be 11 char cmd[2];
cswiger 0:0b271f6ca9be 12 wait(30.0); // give user time to connect to serial port
cswiger 0:0b271f6ca9be 13
cswiger 0:0b271f6ca9be 14 cmd[0] = 0x01; // change address command
cswiger 0:0b271f6ca9be 15 cmd[1] = 0x21; // new address
cswiger 0:0b271f6ca9be 16 i2c.write(addr8, cmd, 2);
cswiger 0:0b271f6ca9be 17
cswiger 0:0b271f6ca9be 18 // update address
cswiger 0:0b271f6ca9be 19 // The above does successfully change the address, but 0x21 won't read until the device is reset
cswiger 0:0b271f6ca9be 20 addr = 0x20; // try 0x20 here, the device is still 0x20 and should read 0x21 from eeprom
cswiger 0:0b271f6ca9be 21 addr8 = addr << 1;
cswiger 0:0b271f6ca9be 22
cswiger 0:0b271f6ca9be 23 wait(2.0);
cswiger 0:0b271f6ca9be 24
cswiger 0:0b271f6ca9be 25 cmd[0] = 0x02; // read address from eeprom
cswiger 0:0b271f6ca9be 26 i2c.write(addr8, cmd, 1);
cswiger 0:0b271f6ca9be 27 i2c.read(addr8, cmd, 1);
cswiger 0:0b271f6ca9be 28
cswiger 0:0b271f6ca9be 29 printf("New address read: %d",cmd[0]);
cswiger 0:0b271f6ca9be 30
cswiger 0:0b271f6ca9be 31 }
cswiger 0:0b271f6ca9be 32