[qldbureau]

"Are you getting a blink of the TX data LED?" - when all is well, lots of blinking, lots of data (of various lengths and timings, both LED's). When not working, only occassional burst, in sync with the LED (the relay LED), about every 30 secs.

When mine is working normally both LEDs blink all the time. Varying lengths and timings for the TX LED, and fairly constantly for the Cumulus one of course only when communicating with the software. Occasionally there is a long pause between all blinks (3 seconds) and they resume. When it has frozen all LED activity stops for good and the screen stops updating. Additionally Cumulus complains that data input has stopped. Using the push button does nothing also.

[werk_ag]

I have put a different plug pack on. I could make up a cable to plug it into a 12 volt battery to isolate noise from cheap plug packs. I have to admit I am loathe to take a soldering iron for removal of parts to my board again - the transistor I had to replace (due to static shock I mentioned in another thread) was very difficult to desolder; however it might not hurt replacing the voltage regulator. I am not convinced the remainder of parts associated with the 12 volts ought to be an issue.

The problem doesn't seem related to the voltage regulator.

Just to eliminate the chance that the problem be the metal case, you can remove all (including the LCD) from the case and test everything again.

[werk_ag]

g'day all - I've had no luck - replaced the RTC - no change - reloaded everything - now worse (!)...

If you have replaced the RTC, don't forget to do a complete system initialization.
If you are using software v1.4 b037 you can do it just by pressing the push button for more than 5 seconds.

Also, forgot to mention, every time on uploading, I get error message "low memory available, stability problems may occur". They're not wrong!!

Yes, they are right, but unfortunately your problem have nothing to do with that message, if it was I could help more!

[werk_ag]

I did some research on google about Arduino USB communication freezes. There are lots of info about it. Most of the times the problem is on the PC side:

- Some USB 3 ports or hubs are problematic.
- Some serial to USB 64 bit drivers are problematic.
- Noise cables

How some people have solved similar freeze problems:

- Change the Arduino to another PC usb port, not on the same hub
- Change the Arduino to one with a FTDI chipset.
- Run the Arduino in a 32 bits system.
- Use USB cables as shorts as possible (One inch is short. 18 inches is an antenna.)

Hope this hints help.

Seems a joke, but it isn't.

I was testing serial communication with the simple code from zoomkat, and I found what was causing this: the refrigerator... that's right, the refrigerator...

This might seem like a bad joke, but I replicated this 4 times today and I didn't believe it either. Every single time the refrigerator turns off, the serial connection just breaks.

The only connections is that the computer and the refrigerator is plugged in the same wall socket.
Being an old fridge, I'm guessing an electric impulse is sent through the wall socket, through the power supply, and somehow messes up the USB port.

Source: http://forum.arduino.cc/index.php?topic=...#msg754337

[FJ rider]

"If you have replaced the RTC, don't forget to do a complete system initialization." - did that,initially nbg, but about 3 or 4 hours later the !@#$ thing came good, data bursts everywhere, outside info, outside battery, all good ! Haven't touched it ! USB connection still locks the thing up - local rf problem ? Starting to think of taking up lawn bowls instead..............! Could it be just a bad rf link, too much noise, other 433 signals ? Can't see it on spec. an. though, and rf sounds clean.....?

[werk_ag]

Forget the RF part... the system does not freeze because is receiving or not RF signals. Concentrate in the USB connection.

There is a thing I can't understand: if the system freeze as soon as you connect the USB cable, how you are able to program it?

Do you close the VP1 switch after programing the unit?

Could you try it in a different PC, in a different location?

[FJ rider]

the program seems to upload without a problem, I close VP1 after I get the "upload finished" message. have tried it on a laptop running XP - same problem. I have replaced a few bits since then so I'll repeat the tests again, and in diff. locations.

At the moment, without a usb cord plugged in, it's running perfectly !!

[qldbureau]

Spent a long day troubleshooting.

1. Reinitialized the RTC. Froze. Disassembled the whole Rx set outside of the metal case and ran it 'naked' on the bench. Froze just after restart.

2. Connect to another computer with Windows 7 - also froze.

3. Discovered that it also froze with no USB cable connected.

4. Remelted and applied more solder to major components.

5. Swapped nano boards and reprogrammed between Tx & Rx unit - still freezing.

6. Replaced RTC module and initialized. Now the RTC EEPROM is listed on I2C memory scanner! Original RTC must have been faulty. Froze when reconnecting USB only.

7. Applied more solder around logger chip.

8. Not freezing now when only connected to 12 volt. Logger is working in this mode. Changed archive to 1 minute so I did not have to wait so long for testing.

9. Occasional freeze when reconnecting USB. Seems ok once restarted and stabilized. Tested several times disconnecting Cumulus and USB, but leaving 12 volts applied. Each reconnect of USB and Cumulus restarts downloaded several fresh archives. Reassembled into box.

So waiting for new USB cable. I think I am about to order an FTDI board.

This is now my full I2C scan result since replacing the RTC:
Scanning...
I2C device found at address 0x27 !
I2C device found at address 0x57 !
I2C device found at address 0x68 !
I2C device found at address 0x77 !
done

[FJ rider]

I've noticed that if I o/c the + and -, and the shield, inthe usb cable, the problem still happens, ie., thing still freezes - not usb power related..........?

[werk_ag]

I've noticed that if I o/c the + and -, and the shield, inthe usb cable, the problem still happens, ie., thing still freezes - not usb power related..........?

What you mean by: " if I o/c the + and -, and the shield, inthe usb cable"

Have you already solved the communication problem with your flash memory?