i2c freeze MCU

[ciko2k]

Hi, i'm using the Wire scan example. if my i2s peripheric is connected the code run well, but when i disconnect the peripheric, MCU freeze and restarted by IWDG

could someone help me? there is an alternative library to use?

Here the code.. thks

`#include

include <libmaple/iwdg.h>

TwoWire WIRE2 (2,I2C_FAST_MODE);

define Wire WIRE2

define TXPIN PA8

int cycle;

void setup() { iwdg_init(IWDG_PRE_32, 8000); iwdg_feed();

pinMode(TXPIN, OUTPUT); digitalWrite(TXPIN,HIGH);

Serial1.begin(9600); Wire.begin(); Serial1.println("\nI2C Scanner"); }

void loop() { iwdg_feed(); byte error, address; int nDevices;

Serial1.print(cycle); Serial1.println(". Scan ***** ");

nDevices = 0; for(address = 1; address < 127; address++) {

Wire.beginTransmission(address);
error = Wire.endTransmission()

if (error == 0) {

  Serial1.print("I2C device found at address 0x");
  if (address < 16) 
    Serial1.print("0");
  Serial1.println(address);

  nDevices++;
}

else if (error == 4) {
  Serial1.print("Unknown error at address 0x");
  if (address < 16) 
    Serial1.print("0");
  Serial1.println(address, HEX);
}    

} if (nDevices == 0) Serial1.println("No I2C devices found"); else Serial1.println("done");

delay(1000); // wait 5 seconds for next scan cycle++;

}`

[GitMoDu]

Without external pull-ups (like the ones likely in your device) I2C will stall because the lines won't raise up. Add fixed external pull-ups and you shouldn't see a problem.

[rogerclarkmelbourne]

Closed due to inactivity from OP