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Posted: Sat Feb 13, 2010 11:23 pm
by EChas3
Perhaps I'm not adequately explaining what I see but I'll take another shot at it. Maybe I can save you the effort of finding & opening an 8910.
I only find three chips. The one up by the Infrared Emitter is probably the processor because it has many more pins than the EEPROM's you sent me.
At the other end of the remote, there are two likely candidates but neither carries a number similar to the EEPROM's you sent me (ATMLH704 - 16B 1 - PGH7083A).
Board Location - Chip Number
U2 ---------------- A51So CH18
U5 ---------------- HT1381 152G0241
Thank you again for your help to this point. If I can determine which of these is the EEPROM, I can replace it.
Posted: Sun Feb 14, 2010 12:39 am
by Kevin Timmerman
U2 is the EEPROM
U5 is the clock
Posted: Sun Feb 14, 2010 12:49 am
by cauer29
EChas3 wrote:Perhaps I'm not adequately explaining what I see but I'll take another shot at it. Maybe I can save you the effort of finding & opening an 8910.
I only find three chips. The one up by the Infrared Emitter is probably the processor because it has many more pins than the EEPROM's you sent me.
At the other end of the remote, there are two likely candidates but neither carries a number similar to the EEPROM's you sent me (ATMLH704 - 16B 1 - PGH7083A).
Board Location - Chip Number
U2 ---------------- A51So CH18
U5 ---------------- HT1381 152G0241
Thank you again for your help to this point. If I can determine which of these is the EEPROM, I can replace it.
On my 8910, U2 is marked A51SC and is connected to the JP1 connector. It's located to the lower right of the CPU blob. The pinout on the eeprom chip is the same as every other I2C eeprom that I've come across. This one is of course, a 2KB eeprom.
A.A.
Posted: Sun Feb 14, 2010 3:28 pm
by The Robman
Here is a pic showing the "U2" location of the EEPROM chip in the lower right corner. The EEPROM chip on this particular remote is labeled "A51SC C431".
You can also see the circular dimple in the lower right corner of the chip that denotes pin1.
Posted: Sun Feb 14, 2010 9:35 pm
by EChas3
Thank you all. U2 it is. I'll reply with my progress.
Posted: Sun Feb 28, 2010 9:54 am
by EChas3
Changing out the EEPROM wasn't all that hard with the right tools. Unfortunately, I still have no joy.
When inserting the batteries, I still get MEM FAULT on the display. I tried the OPS RESET & get the BAD E2. The MFR RESET does the same thing. It also gets a BAD E2 when I load a setup from IR. I guess my 8910 is toast.
I appreciate any suggestions. It may be important to note that the replacement EEPROM's from Robman are a different chip number than the original. (Details in earlier my posts.)
Meanwhile, I'll add a pin block to my old 7800 and see if I can get it to do the job for me.
Thanks for all the help to date.
Posted: Sun Feb 28, 2010 1:40 pm
by The Robman
Hopefully these are silly questions, but are you sure that you have the EEPROM in the right way round and don't have any shorts between pics 6-8 (it's ok for pins 1-4 to be shorted).
You've exhausted my electronics knowledge I'm afraid. Maybe one of the electronics experts can suggest whether a capacitor could be bad, or something like that.
Posted: Sun Feb 28, 2010 4:53 pm
by EChas3
The Robman wrote:Are you sure that you have the EEPROM in the right way round and don't have any shorts between pics 6-8 (it's ok for pins 1-4 to be shorted).
Maybe one of the electronics experts can suggest whether a capacitor could be bad, or something like that.
The new ones are different chip numbers but I put one in the same way as the old one. I didn't see the 'dot' near PIN 1 but positioned the lettering the same way.
Maybe someone can suggest something else.