SY-41CL lock up current drain

[JurgenRo]

Inadvertently I've tried to plugging a non existent Rom Image. The machine locked and showed @s in the Display. I removed batteries and let the machine sit on my shelf without batteries for full 2 month in hope to drain the current from the board that way. Today I inserted the batteries again and ... the 41CL is still locked up, same behaviour as before.
Before I'm going to disassemble the machine in order to get the current from RAM, I'd like to ask if anybody out there has some some experience about the time needed to get all of the current off the board (in this case: V4-board).
Thx, Juergen

[Monte Dalrymple]

(12-15-2016 07:38 PM)JurgenRo Wrote:  Inadvertently I've tried to plugging a non existent Rom Image. The machine locked and showed @s in the Display. I removed batteries and let the machine sit on my shelf without batteries for full 2 month in hope to drain the current from the board that way. Today I inserted the batteries again and ... the 41CL is still locked up, same behaviour as before.
Before I'm going to disassemble the machine in order to get the current from RAM, I'd like to ask if anybody out there has some some experience about the time needed to get all of the current off the board (in this case: V4-board).
Thx, Juergen

Several things to check:
1. Press SHIFT-4 (BEEP) to see if it's really locked up or just a display sync problem.
If it beeps it's just a display sync problem.

2. With the batteries out, press and hold ON for a few seconds. This triggers the
power supply to try to power-up the FPGA, which will drain any residual charge
from the caps in the power supply. The discharged power supply will usually fix
the issue eventually. I think that there is some state in the display drivers that
_really_ needs the power to go away before it can exit it, but I'm not sure. Don't
turn the machine on immediately after inserting the batteries.

3. I once had to wait several days to recover from what was effectively the same
thing. (I erased the Flash page where the YFNX lives... forgetting that once it was
gone there would be nothing to return to after the erase completed.)

It might take several tries, but the ON with no battery always gets things going
eventually.

[Ángel Martin]

(12-15-2016 07:38 PM)JurgenRo Wrote:  Inadvertently I've tried to plugging a non existent Rom Image. The machine locked and showed @s in the Display. I removed batteries and let the machine sit on my shelf without batteries for full 2 month in hope to drain the current from the board that way. Today I inserted the batteries again and ... the 41CL is still locked up, same behaviour as before.
Before I'm going to disassemble the machine in order to get the current from RAM, I'd like to ask if anybody out there has some some experience about the time needed to get all of the current off the board (in this case: V4-board).
Thx, Juergen

Not sure if this is myth or has a scientific ground, but one thing that has helped with this issue at times was to plug the serial connector (with the batteries OUT !!). This may have been coincidentally to other actions, sure enough Monte's description above sounds a better approach.

[aurelio]

I had the same behaviour, plugging a non existent ROM image a few weeks ago, twice
the first time was locked with all @ a whole day, without batteries, the second time two.
I was scared and I took it apart several times before to ask Monte for help, thinking to a bad contact problem
He suggested me the step two, it works

It happened again just two times after that and the restoring time was, then, just a whole hour.

[JurgenRo]

Thank you so much for your advice! Will try the suggested recovery procedures tomorrow - will let you how it went! Thanks again!!

[JurgenRo]

Finally, I tried all oft the suggested procedures: stand alone, in combination and with various parameters (e.g.duration time of pressing the ON-button). Alas, nothing helped, the machine ist still locked up and it does not respond to the Shift 4 with a beep either. The only difference is that once in a while the „lock-diplay“ changed from all @s to something like 7???,,??....

By the way, I forgot to tell that the machine has got a new IO-block Flex PCB replacement (another great item from Diego!). Don’t know if this might have some influence?

Thank you again for your help!
Juergen

[Geoff Quickfall]

Okay,

The other things don't work. Was the calc in the process of writing to flash. Was there a power interrupt between or during the process. A power interupt will corrupt the CL board and require a reflashing of the board.

You mentioned Deigo's new io strip. Was it working for flash read and writes prior to this problem or was this a first run with the new strip. The io strip will not affect the CL board except for power interruptions ie. the power connect points which need to be aligned perfectly. The board requires good batteries and a perfect contact at the IO strip and the zebra (wire wrap) strip at the base.

I mention this as I installed a Deigo io strip which ran perfectly, looked perfect but one of the modules port was acting up. The strip was misaligned just enough to interrupt the contact with a minor flexing of the case. I had to heat the io block up, remove the strip and realign it. Then it worked.

I am mentioning the power interrupt now as it sounds like a corrupted board which may need reflashing.

Monte et al may have further suggestions.

[JurgenRo]

Hi Geoff, nice to read from you!

There was no Flash write in progress. I just plugged a ROM Image from a RAM address. Unfortunately, I did forget to copy the ROM at that very address. So, nothing was there that could be plugged and things went south.

Also, the IO-Strip from Diego worked and works perfectly reliable. So, I do not think that it is a Flex Strip issue.

Thanks a lot, Goeff!
Juergen

[aurelio]

Hi Juergen did you succed to unlock it?

[JurgenRo]

(02-06-2017 06:52 PM)aurelio Wrote:  Hi Juergen did you succed to unlock it?

Hi Aurelio!
Yes eventually I did! :-) But I had to dis-/reassemble the machine. I posted my experience here (sorry, should have actually better used this very thread!):

41CL back to life

Thanks again and all my Best,
Juergen

[aurelio]

Thank-you Juergen, I asked it because.........
..........my calculator is again locked with "all @s"
screws seems to work correctly, the last time when it happened I succeded in fixing it as you did, loosing and tightening them, but this time I cannot find the right pressure for which the machine is perfectly working!

My brother should call it the "..." point

I'm pretty sure the posts are in a good shape, I feel it, tightening the screws, but there is no way, yet.... I've re-assemled the machine with much care for the RS232 cable path, assuming that its presence could be interfere with the coupling, even I removed it, but it's not that

[JurgenRo]

I'm very sorry to hear, Aurelio :-( That's why I'm using my machine very carefully now - I feel that this "sweet spot" is very sennsitive. Do you use Diegos Flex board? I've just good experience made with it, works great! I wish you success in recovering the operating point!

Good luck and let us know how it went!
Juergen

[Monte Dalrymple]

(02-10-2017 07:34 PM)aurelio Wrote:  Thank-you Juergen, I asked it because.........
..........my calculator is again locked with "all @s"

1. Remove the batteries.
2. Press the "ON" button (to discharge the power supply caps.)
3. Insert the batteries.
4. Press the "ON" button.
if the display doesn't say "MEMORY LOST" try the following:
5. press backspace
6. press SHIFT "4" (if the machine BEEPs it's a display problem.)
7. press "ALPHA" "T" "U" "R" "B" "O" "X" "ALPHA"
8. press backspace (and the machine should come alive.)
9. turn the machine off and the press backspace-ON to get "MEMORY LOST"

[aurelio]

(02-10-2017 08:54 PM)JurgenRo Wrote:  I'm very sorry to hear, Aurelio :-( That's why I'm using my machine very carefully now - I feel that this "sweet spot" is very sennsitive. Do you use Diegos Flex board? I've just good experience made with it, works great! I wish you success in recovering the operating point!

Good luck and let us know how it went!
Juergen

I used Diego's flex for other calculators, but this is not the case...the original one is in a perfect shape

I even swapped the golden connector (not the foam one) @@@@@ and again @@@@@@s.......today she took too much time, it's too late...out the battery pack ....sleep again in the drawer, baby

[aurelio]

(02-10-2017 09:11 PM)Monte Dalrymple Wrote:  

(02-10-2017 07:34 PM)aurelio Wrote:  Thank-you Juergen, I asked it because.........
..........my calculator is again locked with "all @s"

1. Remove the batteries.
2. Press the "ON" button (to discharge the power supply caps.)
3. Insert the batteries.
4. Press the "ON" button.
if the display doesn't say "MEMORY LOST" try the following:
5. press backspace
6. press SHIFT "4" (if the machine BEEPs it's a display problem.)
7. press "ALPHA" "T" "U" "R" "B" "O" "X" "ALPHA"
8. press backspace (and the machine should come alive.)
9. turn the machine off and the press backspace-ON to get "MEMORY LOST"

Hi Monte, performed the 9 steps unsuccesfully

I've already tryed to discarge the caps with the "ON", as I read in the previous
when I insert the battery pack the calculator seems dead, but pressing in the middle or in the bottom of the case both sides I get all@s pressinf again is dead...
but when the display shows all@s the calculator does not respond
"ALPHA" "T" "U" "R" "B" "O" "X" "ALPHA" I suppose is to be pressed when the calculator is "on", I mean with the @s .....by teh way nothing even when blank

edit
pressing SHIFT "4" if the machine does not BEEP!

[aurelio]

............now, at the 1,5643 rd attempt, found the "..." point
newer so happy in seeing a MEMORY LOST

I don't know what really happened but the screws were very loose, after that with a machine reset, I can tighten them to close safely the body.
I would like to understand what kind of reset is made on the machine through this "mechanical" procedure.

[JurgenRo]

(02-11-2017 11:43 AM)aurelio Wrote:  ............now, at the 1,5643 rd attempt, found the "..." point
newer so happy in seeing a MEMORY LOST

I don't know what really happened but the screws were very loose, after that with a machine reset, I can tighten them to close safely the body.
I would like to understand what kind of reset is made on the machine through this "mechanical" procedure.

I know what you mean, felt the same the other day!

If I understood Monte and other experts here correctly, then this "procedure" yields in a complete drain of electrical charge (which is responsible for the RAM-garbage that locks the machine) from the 41cl board. But I'm really not sure here

Juergen

[aurelio]

(02-11-2017 08:49 PM)JurgenRo Wrote:  

(02-11-2017 11:43 AM)aurelio Wrote:  ............now, at the 1,5643 rd attempt, found the "..." point
newer so happy in seeing a MEMORY LOST

I don't know what really happened but the screws were very loose, after that with a machine reset, I can tighten them to close safely the body.
I would like to understand what kind of reset is made on the machine through this "mechanical" procedure.

I know what you mean, felt the same the other day!

If I understood Monte and other experts here correctly, then this "procedure" yields in a complete drain of electrical charge (which is responsible for the RAM-garbage that locks the machine) from the 41cl board. But I'm really not sure here

Juergen

after removing the batteries for a while (while calculators taking rest), both the machines "all @ syndrome" tomorrw I'll call the doctor now it's too late