BlinkMs loose unit addresses at random!

The bus length is -long-, about 4 feet (they are being used as indicator lamps in a pipe organ console). However I've slowed down the clock/data speed to very slow (sorry I don't have exact timing). There are 4.7k pull-ups at the end of the bus. I had to write standalone bit-banging code to drive the bus as the standard rate on the Arduino board was way too fast. The only command I send to them is the change color command. I do have to update all 14 of them as quickly as possible regularly; I sequentially access each one, setting it's color, every second or so for all of them.

I did numerous tests to determine a max speed for the bit-banging code, and backed off to a safe speed that works reliably. The code uses the Microsecond delay call for timing, about 20us for each bit. I've run the code as slow as 1ms per bit with the same issue of random loosing of the programmed address.
I do get proper 'ack' feed back on each byte transmitted.

A possible scenario is that the glitch occurs when power is lost while sending data. The system may be powered off by the user at anytime, including while I'm sending to the BlinkMs. If I remember correctly, I think the problem happened mostly when I did power on/off tests. Sorry I can't be more specific as each time it happened (at least 5 times yesterday), I had to stop, remove the bad blinkm(s), reprogram the address, and reinstall; making for a rather frustrating day.

Hope that helps.

Btw, I did check the signals on the data and clock lines with a scope... they are clean with good rising and falling edges.

I'll try to get some code for you when I get back to the office on Tuesday.

Hi Guys,
Has any progress been made with this?
I have a project coming up with 16 blinkM's.

I have experienced this problem too-- it is very annoying. I purchased a very large amount of BlinkMs because I thought they would be more reliable as a networked array of leds opposed to a wire to teach LED, but this makes it probably less reliable. I am using 14 BlinkMs on an ribbon cable similar to the Cylon project; one time while filming the project I tried updating an led to a different color and bam, it and the one next to it lost its address. :( The operating system also said that USB had been unplugged (it had not been) probably meaning the Arduino reset. If you'd like to see code, please let me know. (though it is very similar to the cylon project)

Any Ideas? My research group is sending this project out to present it a few states away and in the UK. If possible, I'd rather not have spent $400 dollars on LEDs and have them botch up 6000 miles away. :(

As an update, one of the BlinkMs that lost its address seems to have died. It now blinks once when powered, and accepts no commands and plays no scripts afterwards. Many others BlinkMs in my shipment arrived like this as well, but I have not had the chance to test all of them.

Thank you.

When reporting to Todd It will be helpful to list the number of BlinkM's online and the type and size of the power supply used as well to help eliminate issues that might be related to power fluctuations or surges during use..

Will

I have the same problem : I use an arduino board, and a strip of ten blinkm. pull up resistor are on the 5v of the arduino and the blinkm are powered with a separated regulator (common GND).
the 4 same blinkm lost their adress when i repower few time everything.

So to detect what is going wrong i wrote a setup wich makes blink each blinkm on each canal of the i2c bus :
////
int i ;
for(int i = 1 ; i <= num_led;i++)
{
BlinkM_setRGB(0x00,0x0,0x0,0x0);
delay(5);
BlinkM_setRGB(i,0xFF,0xFF,0xFF);

delay(300);
Serial.print("canal : "); Serial.println(i);
}
////

After a reprogrammation and some reboots + sequence, i found that it is the same leds wich lost their adress and have most of the time taken an adresse of an other led between the losts leds . Whatever, they respond to canal 0

Maybe it is the corruption of a bit in the address. Is there some CRC made on the adresse in the attiny45 of the blinkm ?

Arnaud

I have reprogrammed the default sequence with communiator and sequencer.
But the concerned led with the problem lost these sequences too. As far as i remember, concerned leds maintained the programmed sequence and the channel number when it stays plugged on 5v. When I unplug and replug power, let say 5 times, almost every concerned led lost their information.

My pull up resistors are on a shield up to the arduino board between 5v of arduino and respectively SDA and SCL. grounds are common between arduino voltage regulator and the dedicated one for leds (78T05N -> 5V 3A for 10 leds and 20 in the futur, with all the capacitors to maintain a perfect 5V even when the leds are blinking -> verified with oscilo).

Best thing i can do is send you the leds concerned asap to let you have a hand on it.
For information, I bought the leds at lextronic (France) 10 days ago.