URC8780 Dead

usblipitor · Post by **usblipitor** » Fri Nov 14, 2003 11:03 pm

I am on a roll (ie I have been wrong in every post of this thread) so here I go for number three! Rob, get ready!

1) From reading other threads, experts have noted that when hooked up to a JP1 cable, the remote's eeprom can be read even though the rest of the remote may be FUBAR. so the fact that you could get read and detect a memory fault may not be all that surprising. what is surprising is that the lcd screen and buttons started working.

2) to me, mem fault means try a new eeprom. if Rob thinks a new eeprom might be worth trying, I think from reading other threads he can send you one quite cheaply and quickly and you can pay conveniently via paypal.

Get your baseball bats and lead pipes, I am waiting for a severe beating for being wrong! At the very least, Rob can start off his note with Strike Three, you are Out!

gjarboni · Post by **gjarboni** » Sat Nov 15, 2003 4:49 am

Umm, strike three? (borderline pitch on the outside corner

) No, I can't blame on this one -- I've revised my answer three times now. Here we go.

Okay, the 8780 has two processors. One controls the LCD and most of the buttons. This processor has an eeprom and this processor and it's Eeprom are connected to the JP1 interface. This processor is a 740 type.

The other processor controls the four learning buttons on the 8780 (1L through 4L). The LED is connected to this processor. We assume this processor is a SAM8, but since all it does is learn, we're not 100% sure.

Somehow the batteries are powering the SAM8 processor but not the 740 processor. But the JP1 interface is providiing enough power to run the 740 processor (that's why you only see the LCD display when you hook up the JP1 interface). So there's some loss of electrical continuity inside the remote. Theoretically you could hook up two wires from the batteries to pins 1&2 (Vcc or + battery terminal) and pin 3 (VGround or - battery terminal) and power the remote that way. However, someone with better electronics skill should double check this.

The MEM FAULT message means that the eeprom data is corrupted. This could be the result of a bad eeprom or just bad data. Since you already have a working 9800 and since the 9800. 8800. and 8780 are all the same remote software wise, you can download the config from your 9800 (save it in IR.exe first) and upload it to the 8780 as a test of the Eeprom. You'll get an error message in IR.exe about signatures being different, but it's okay to ignore it. If you don't see the "MEM FAULT" message on the screen than it looks like the EEprom is good.

pro_tron · Post by **pro_tron** » Sat Nov 15, 2003 8:10 am

Thanks to everfyone for all the help. Do you mean a jumper from the battery terminals to JP1 pins to feed power in to simulate having it connected to the computer, or are you saying to the pins on the IC?

gjarboni · Post by **gjarboni** » Sat Nov 15, 2003 9:39 am

pro_tron wrote:Thanks to everfyone for all the help. Do you mean a jumper from the battery terminals to JP1 pins to feed power in to simulate having it connected to the computer, or are you saying to the pins on the IC?

I meant a jumper from the battery terminals to the JP1 pins. Definitely much easier than soldering to the IC.

Post by **The Robman** » Sat Nov 15, 2003 4:26 pm

pro_tron wrote:... Unfortunately the URC8780 is not a device that IR covers ... My cable and IR software works great with my URC9800 ... Is the URC8780 an uncommon remote?

Internally, the URC-8780 and the URC-9800 are exactly the same remote. I think, reading between the lines, that you are saying that IR.exe doesn't recognize the download from your URC-8780, which if true, definitely confirms that you have screwed up the data there somehow. Do as Jason described and load the memory dump from the URC-9800 back into the URC-8780 and see where that gets you.

pro_tron · Post by **pro_tron** » Sat Nov 15, 2003 8:36 pm

The Robman wrote: Do as Jason described and load the memory dump from the URC-9800 back into the URC-8780 and see where that gets you.

Ok. I am going to try that just as soon as I figure out how.
Thanks

Post by **The Robman** » Sat Nov 15, 2003 8:51 pm

pro_tron wrote:
The Robman wrote: Do as Jason described and load the memory dump from the URC-9800 back into the URC-8780 and see where that gets you.
Ok. I am going to try that just as soon as I figure out how.
Thanks

Here's a step by step...

1) Fire up IR.exe
2) Connect the URC-9800 to the JP1 cable
3) Download the memory
4) Connect the URC-8780 to the JP1 cable
5) Upload the memory (if IR gives a warning about different signatures, ignore it)

pro_tron · Post by **pro_tron** » Sat Nov 15, 2003 9:20 pm

Oh. I can do that. I was making more complicated then it needed to be.

pro_tron · Post by **pro_tron** » Sat Nov 15, 2003 9:26 pm

Great! I no longer get the mem fault when I plug the interface in. However the remote is still dead when I disconnect it. I am going to try to trace out which wires go where on JP1 and try the jumpers to the batteries to see if it will power up.
Thanks again.

gjarboni · Post by **gjarboni** » Sat Nov 15, 2003 11:58 pm

pro_tron wrote:Great! I no longer get the mem fault when I plug the interface in. However the remote is still dead when I disconnect it. I am going to try to trace out which wires go where on JP1 and try the jumpers to the batteries to see if it will power up.
Thanks again.

Pins 1&2 (left most top & bottom) should be connected to the + battery terminal and pin 3 (middle pin bottom row) should be connected to the - terminal.

pro_tron · Post by **pro_tron** » Mon Nov 17, 2003 8:50 pm

Well that did not work either. I give. I have a new 8910 on the way. Maybe the Robman can have this one and see what he can find. Thanks again to all for the help.