Hi,
I have had two separate BeagleBones now, both RevA5A, and both have had the same problem. I have used them both with the same RevA2 3.5" LCD cape and maplin 5V 2.5A power supply (One of these may be the problem?), and had them both running the latest Angstrom image. The first Bone BB1 loaded the Angstrom log in prompt on the LCD, then instantly restarted and wouldn’t boot up again, it would just power up, USR 0 and 1 would flash for 2 seconds, then the process would start again. BB2 was working perfectly with the LCD, I was running python programs, viewing the web browser through a USB Wifi connection etc, then after about a week i went to boot the board as i had many times before, however this time it just did exactly the same as BB1, and wouldn’t boot, or with the LCD and WIFI removed wouldn’t even power up through the USB. It powers up with the 5v power adapter, for a while, these are the voltage values I get before the board reboots and they return to 0V before rising again.
VDD_3V3EXP: 3.31 V
VDD_5V: 5.1 V
SYS_5V: 5.2 V
PWR_BUT: 0 V
SYS_RESETn: 3.26 V
Have I damaged the hardware on the board? or are these values expected from these pins? If anyone has any ideas as to why the board wont boot it would be hugely appreciated!
Thanks, Sam
The PWR_BUT should not be 0V. Have you tried both boards without the LCD attached?
Gerald
Yer, both boards have the same problem without the LCD attached. Unfortunately its for a university project, so to get a replacement board I had to give them the old board, so I didn’t have chance to check the values of the pins on that board, but i’ll see if i can get hold of that board tommorow and check if the values are the same.
I don’t think they will give me another board after the repeated problem, so im determined to find a solution for this board!
Do you know of anything that could be causing the PWR_BUT to be 0v?
Thanks for the quick response, Sam
If the LCD is an issue, it needs to be looked at. Go ahead and request a RMA now. The PWR_BUT only have something on the LCD. There is nothing that connects to it on the BeagleBone.
Gerald
I was unable to check the voltages on BB1, but i was discussing the issue with my lecturer and they seem to think there may be an issue with drawing too much current from the power supply for the onboard regulator? As im trying to power the LCD screen and a USB WIFI hub at the same time.
Do you know if this could be an issue? otherwise the only other option i can think of is that its the LCD or the power supply that is killing the boards and il submit an RMA.
Sam
There is no on board regulator that powers the LCD. It has a dedicated regulator but it does get the main power form the same source, the USB. If you draw more than 500ma for the USB it will shutdown. Period. So, the idea of powering the board and the LCD form USB is a waste of time. You need an external DC supply of at least 1.5A.
Gerald
I was powering the whole device (LCD, Bone, WIFI) from a 5V 2.5A power supply i know the USB wouldn’t supply enough power. I am not very knowledgable on the hardware side, this was just a suggestion from one of my lecturers that the Bone couldn’t handle the LCD and the WIFI USB hub at the same time? And eventually killed the board.
How does the RMA process work? Should i send both the LCD and the Bone? How long does it take?
My problem is that its used for my final year project, and because of this the longer i don’t have the board the further i will fall behind, sorry to be pain with all the questions.
Sam
Our RMA is for the BeagleBone only. You need to contact BeagleBoardToys for RMA on the LCD.
Just do as I say. Place the separate RMAs and you will be taken care of.
Gerald
Both RMA’s submitted, thanks for the advice!
Sam
The RMA for the BeagleBone has not shown up.
Gerald
I have clicked submit several times.
This link below is for the RMA?
http://beagleboard.org/support/rma
It brings up a message to ok the request or cancel, and iv ok’ed it several times.
Sam
I will keep looking for it, but so far, no RMA request has been received.
Gerald
Still no RMA. Send a direct email to rma@beagleboard.org with the asked for information typed into the email.
Gerald
Done. Sorry for the late response, was at university attempting to complete the form, so head home just in case it was there network that wouldn’t send the email. Manually sent you the form in an email now.
Sam
Yes, just came in. You should be contacted shortly.
Gerald