Industruino RTC


Today I've been following the example of this guide about the RTC: and I've uploaded the example code, I've found that, after doing that, when I try to read the mac of the industruino the board gets stuck, the method I use to read it is the same of the Industruino ethernet client example: 

void readMACfromRTC() {
  Wire.begin();                                 // I2C for RTC MAC
  SerialUSB.print("Reading MAC from RTC EEPROM: ");
  int mac_index = 0;
  for (int i = 0; i < 8; i++) {   // read 8 bytes of 64-bit MAC address, 3 bytes valid OUI, 5 bytes unique EI
    byte m = readByte(0x57, 0xf0 + i);
    SerialUSB.print(m, HEX);
    if (i < 7) SerialUSB.print(":");
    if (i != 3 && i != 4) {       // for 6-bytes MAC, skip first 2 bytes of EI
      mac[mac_index] = m;
  SerialUSB.print("Extracted 6-byte MAC address: ");
  for (int u = 0; u < 6; u++) {
    SerialUSB.print(mac[u], HEX);
    if (u < 5) SerialUSB.print(":");

Also I've realized that with the example code of the RTC my industruino doesnt show the datetime. I've tried the RTC example without using a CR1220 battery, so in the code, the first time I've uploaded it I put RTCind.start() to false (I don't know if its correct, thats what I've understood reading the comments near the method call).

Many thanks in advance.



| 0 0 0
Asked on 11/8/21, 10:30 AM

Hi! I use with success this library: That have built in the function for read (and write) the eeprom

Enrico Michieletti
on 11/9/21, 9:13 AM

Hi Enrico, I'll take a look of that library, maybe it can fix the problem, thanks :)

on 11/10/21, 10:52 AM

Hi, please start with the example code unmodified and tell us what happens exactly. for MAC address, note that with the code will wait until SerialUSB is connected (Serial Monitor) for RTC, also without battery

| 1 1 3
Answered on 11/9/21, 1:34 AM

Hi Tom, many thanks for your reply! I've tried those two examples unmodified, as you asked me to do and: 1) With the first one, the sketch uploads and the Serial monitor prints: "Get unique MAC from RTC EEPROM READING MAC from RTC EEPROM" and nothing else, the Industruino LCD backlight stills on, but nothing is printed in the screen. 2) With the second one, the serial monitor doesn't print anything and the Industruino screen prints: "RTC DEMO" one time.

on 11/9/21, 8:21 AM

Hi, assuming you have an INDIO version, can you confirm that you are powering it with 12/24V on the V+/V-. If yes, can you send us an email with the revision number and serial number of the topboard, to - you will have to remove the casing, and the numbers are on the top of the topboard next to the LCD

on 11/10/21, 1:23 AM

Hi Tom, my model is a PROTO D21G, I've tried powering it with 12V/1.5A and I have the same results, I'm sending you an email with the revision and serial number.

on 11/10/21, 8:15 AM

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Asked: 11/8/21, 10:30 AM
Seen: 993 times
Last updated: 11/10/21, 10:52 AM