D50 - Battery Change - Now NO LCD/Sound - Help!!!

[goodguy]

My Roland D50 was working fine (other than 3 inactive keys, solved by resoldering a trace that affected those keys).
Before battery change, had all sounds and functionality.

While I had the D50 open, decided to change the Cr2032 battery.
Closed it back up and now I get a blank LCD display & no sound. HELP!!!

I can select the upper/lower/value/local buttons and the corresponding red indicator changes next to the selected button. If I select the write or data transfer buttons, I can then only select the value and local buttons (I think this is normal), If I then hit EXIT, I can then re select between the upper/lower/value/local buttons again. So it appears the function logic is working in the background - BUT - I cant see anything on the LCD.

Hard to believe just changing the battery would make the LCD blow out? LCD was working fine before changing battery. Any way to test LCD without spending big $ on replacement LCD only to find out it's fine.
Guessing I have lost something like the Operating System and/or Eprom??

A web search indicates others have had the same thing happen upon changing the battery (but no posted fixes) - so pretty sure it's more software related than hardware (i.e. bad cable, etc ... checked and everything looks connected as normal).

Any ideas that can get me back on track?? Might it be as simple as a reload of software (but blank LCD would indicate its more than just a patch reload or I would have some boot LCD text).

Any help is appreciated.

Whadda you think --- New EPROM, software reload steps (no display to see whats happening), wrong battery (lithium vs other cr2032?), connections or something related to changing the battery (or what to test next).

Note: I did unscrew the main board to change battery and fix keys. But, I unscrewed the main board before with no issues - it was only upon changing battery everything went blank.

HELP!!! I'm stuck and hoping my D50 is not a brick :-(

[qqquartzzz]

I'm no expert on the D50, but, can you maybe boot it up in diagnostic mode?
Hold "0" and "DECREMENT" and then turn power on.
You can look at the service manual here for more info:
http://www.polynominal.com/site/studio/ ... manual.pdf

Then there's always the factory rest:
https://www.sweetwater.com/sweetcare/ar ... -settings/

You'll need a sysex or .mid of all the sounds to Xfer back to your D50. Unless you have them on a ROM card.
If you need the original factory sounds; you can get them here.
http://bobbyblues.recup.ch/roland_d-50/ ... banks.html

Hope it helps.

[goodguy]

Thanks very much for the suggestions - will check them out.
Problem is. the display is blank so will not show anything which makes it impossible to perform recovery functions.
Pretty sure it is not a bad display. I have opened the KB a few times and never had any issues - careful to never move any cables unnecessarily. It coincided exactly with the changing of the coin battery (changed battery, closed it up, plugged in and nothing).
Apparently other D50 owners have had this happen and some have suggested the OS was lost upon battery change.
SO, how to activate bootloader and reload OS? Or maybe Eprom needs replacing...
Any ideas are greatly appreciated.

[Miks]

Apparently other D50 owners have had this happen and some have suggested the OS was lost upon battery change.
SO, how to activate bootloader and reload OS? Or maybe Eprom needs replacing...

Nah - the OS doesn't get lost if the internal battery is dead and/or was replaced - it normally is located in an common Eprom. This could also be an OTP-type (OneTimeProgrammable) which can not be erased and re-written with new data or a so-called Mask-Prom which is already programmed with the OS data while being manufactured (not erasible too). They all could be replaced too by an appropriate EEprom...

The latest firmware (OS) versions:

Version 1.10 Operating System

for ROLAND D-50 and D-550

Final OS Version for early versions of these instruments
D-50: Serial No. 868199 and below
D-550: Serial No. 869949 and below
(IC 22 on Main Board)

How to check your current OS version:
D-50: Hold the ZERO button on the number pad and INCREMENT, then switch the power on.
D-550: Hold PATCH BANK 6, PATCH NUMBER 6 and EXIT, then switch the power on.

Upgrades after 1.0 were mainly bug fixes, but Version 1.10 adds the following features:
Program Change Number can be transmitted. Patch Dump can be made through exclusive
message. Portamento and Hold effects can be given independently on each tone in Dual
Key Mode. The method of setting separate channels has been changed.

Some of the instruments have the OS in a MASK ROM:
IC LH531306. These can also be replaced by this Eprom.

---------------------------------------------------------------------------------------------------

Version 2.22 Operating System

for ROLAND D-50 and D-550

Final OS Version for later versions of these instruments
D-50: Serial No. 868200 and up
D-550: Serial No. 869950 and up
(IC 22 on Main Board)

How to check your current OS version:
D-50: Hold the ZERO button on the number pad and INCREMENT, then switch the power on.
D-550: Hold PATCH BANK 6, PATCH NUMBER 6 and EXIT, then switch the power on.

Version 2.10 added the following features:
Program Change Number can be transmitted. Patch Dump can be made through exclusive
message. Portamento and Hold effects can be given independently on each tone in Dual
Key Mode. The method of setting separate channels has been changed.

Version 2.22 fixes some bugs in 2.12 - it had problems caused by lack of memory space.
This was solved by removing the key transpose function. In V.2.22 the transpose now has
to be executed by using +/- instead of the keyboard. A bug, that caused problems when
transmitting a special program change number, was also removed.

Some of the instruments have the OS in a MASK ROM:
IC LH531306. These can also be replaced by this Eprom.

This OS can NOT be used for D-50 or D-550 with lower serial number.
For these, Version 1.10 adds the same features as described above.

[goodguy]

SOLVED (After a battery change, had a non working display and lost all sound):

FIX:
Tested for +/- 12 v to display (white and black wire), discovered black display power wire (from power supply) was pinched under a screw.
Resoldered/fixed wire & display worked again. But due to battery change I had lost all memory.
Used Sysex Librarian & Bin files from Bobby Blues site (had to convert BIN to sysex first using http://www.difficultaudio.com/roland.php).
Reloaded D50 with sysex file (TuneFunction>Protect Off>Data Transfer>BulkLoad>) & viola - works perfectly !!!

Thanks very much for your help and input!!!