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Old 10-02-2018, 05:01 PM   #81
dkneyle
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

If, as it appears, your ROMs have rotted over time, then there is hardly any point trying to pull them and read the codes. That's what I did; sent them off to an enthusiast in the UK who read them and confirmed they were corrupt. Unless someone manages to get a good read of all three ROMs you (and anyone else with the same issue) have no chance to get things going again. With the correct ROM code it is simply a matter of burning to compatible EPROMs. But we need the good code first.

Sorry my friend, but you have gone up the same dry gulch as many before.
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Old 11-22-2018, 08:24 AM   #82
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Smile Re: Yamaha Electric Piano CLP550 no keyboard output

Hello friends, Thanks for the lot of effort made on the clavinova 550 so far. me too now having a unit to repair with NO sound or some strange distortions on certain key puches. so i follow the whole thread and learn alot.

i had gone through my case before read this thread and refering the circuit diagram and i was end up with decision to change the DAC chip first. but it seems i have more things to consider.

i noted the circuit of my case had not done any repair so far and problem occurred after idle for year or so. so im quite convince the fault will not cure after replacement of DAC and few other digital chips support mux n chip enables(Hex inverters). anyway im trying my luck in coming few days if i was able to procure the DAC locally or i have to wait 3~4 weeks to arrive it from Ebay. in the same time im planning to remove ROMs carefully to read them and make a dump. fortunately i have all the stuff to do so with me already. if the luck is in our side n if we able to read ROM-A, we have have whole lot with collection of your previous efforts.

i had checked the availability of 27C040 ROMS( or even AT27C040 from ATMEL from more recent era) and those are available to order and my EPROM reader\programmer well supporting those. so hope for the best!

Thanks guys for your endless effort from 2014, long way back!, will update you the progress!

by the way: let me introduce my-self, im PMD from Sri Lanka, Engineer and experienced Repairman(as part of the job and as a hobby) for many years. experience in Electronics, component level repairs in analog and digital systems, embedded system design and programming, Electrical Engineering...

PMD.
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Old 11-22-2018, 03:00 PM   #83
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

It certainly appears that if the piano is not used for a period of time then the ROMs fail. Reading this thread, that appears to be a common theme. I too changed the DAC but of course that didn't fix the problem. So if you are able to recover good code from the final ROM then perhaps there is a pathway to reflash some ROMs and get it going? Even though I no longer have the piano (actually I could still access it if I hear that anyone succeeds with this strategy) then it would be a great conclusion to this thread.
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Old 12-10-2018, 12:36 AM   #84
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

I was working on my CLP550 and got replacement EPROM AM27C040 and had read my existing chips. two were readable quite well and files attached here. basically the missing image from previous attempt also recovered. but only one rom we both recovered by seems some slight differences in some areas. pls refer attached images if any one interest to some forensics. i manged to read rom A & C. third ROM was just reading first 2 or three bytes but from that point nothing readout. i dont have control over reading pulse time of data settling time after address latch. so might get better results with slower clocks. my reader took around 7500ms to read the whole memory, 14us per byte, might be ok.

will update after while the developments.
Attached Files
File Type: rar Wave Rom Images.rar (404.9 KB, 19 views)
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Old 12-10-2018, 03:25 PM   #85
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

STJ is the expert here who knows about ROM chips. He might be in a position to understand the discrepancy in the code recovered from those two chips. What we really need now is someone with a defective piano to burn the code to new EEPROMs, install and see if it brings the piano back to life.
We have never categorically determined the ROMs to be the problem, although STJ did confirm that the code in my ROMs was garbage or unable to be recovered.
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Old 12-11-2018, 05:38 PM   #86
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

The 27C040 4Mb/512KB 32-pin EPROM is an asynchronous read unit, and the only sequenced section is reading the deviceID and manufacturerID. These typically have less than 100ns read times so 14s/byte is reasonable.

These are wavetable ROMs? What happens if they get interchanged?

What do you mean by "nothing readout" and "first 2 or three bytes"? What are you reading out on the "bad" one, as they are asynchronous they shouldn't give much information about read failures, just returns bad information.
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Old 12-12-2018, 04:14 AM   #87
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Yes, it is our understanding they are wavetables. Not sure if they are interchangeable or not? The circuit diagram certainly shows some logic goes on concerning the chip select (CS) line, which might suggest they are intended to only go in the dedicated slot they are intended for?
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Old 12-15-2018, 09:04 PM   #88
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

hi, i were managed to check the CLP 550 with 27C040 ROMs burn with given images. and piano is working!!. i checked the DA converter as well but it working fine. i think previous conclusion of wave ROMs are rotten is correct. even i read the two ROMs just after remove from the board but does not respond to reader few days afterward(i just wanted to read again and compare few reads to see how much consistent the contents of ROMs). but no chance now.

Quote eccerr0r:
"What do you mean by "nothing readout" and "first 2 or three bytes"? What are you reading out on the "bad" one, as they are asynchronous they shouldn't give much information about read failures, just returns bad information. "
I try to read the 3rd chip but after first 2 or 3 address, all remaining adress readsout "FF" or yeilds no output so my output window just shows 1F, 03, A2 then FF, FF, FF till the end. seems chip have error in address decoder area.

with ROM B and C unit is working almost. only the default tone(Grand piano-1) chord area working and reaming keys giving no output but all other 7 tones working. with given ROM A, remaining areas also working, but in my case some noices are added witch i cant eliminate(to all the tones with or without ROM A). i suspect two reasons. one is some data bytes of the roms are incorrectly reads and that causes the issue. also i notices IC15 & IC16 getting some decoding pulses from IC12 and it does the stereo decoding and having some voltage issue in SH3 pin(only 0V - no change over any tone or any function). im further checking on changing these digital chips and let you know in due course. i found all the voltages in remaining areas correct. any suggestions and guide lines are mostly welcome. my CLP550 tones getting slight distortion and at the end of the tone the distortion can here quite well and once toning period end, all noises vanished.
Attached Images
File Type: jpg 1.jpg (558.7 KB, 18 views)
File Type: jpg 2.jpg (500.1 KB, 16 views)
Attached Files
File Type: rar clp 550 CLAVINOVA.rar (751.4 KB, 10 views)
File Type: rar CLP550_OA_C.rar (563.6 KB, 8 views)
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Old 12-18-2018, 10:25 PM   #89
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Great to know. You have proven it is the ROMs which are at fault. Well done, and now we have a copy of Yamaha's ROM code available in the world wide web!
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Old 12-21-2018, 05:26 AM   #90
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Quote:
Originally Posted by PMD View Post
hi, i were managed to check the CLP 550 with 27C040 ROMs burn with given images. and piano is working!!. i checked the DA converter as well but it working fine. i think previous conclusion of wave ROMs are rotten is correct. even i read the two ROMs just after remove from the board but does not respond to reader few days afterward(i just wanted to read again and compare few reads to see how much consistent the contents of ROMs). but no chance now.

Quote eccerr0r:
"What do you mean by "nothing readout" and "first 2 or three bytes"? What are you reading out on the "bad" one, as they are asynchronous they shouldn't give much information about read failures, just returns bad information. "
I try to read the 3rd chip but after first 2 or 3 address, all remaining adress readsout "FF" or yeilds no output so my output window just shows 1F, 03, A2 then FF, FF, FF till the end. seems chip have error in address decoder area.

with ROM B and C unit is working almost. only the default tone(Grand piano-1) chord area working and reaming keys giving no output but all other 7 tones working. with given ROM A, remaining areas also working, but in my case some noices are added witch i cant eliminate(to all the tones with or without ROM A). i suspect two reasons. one is some data bytes of the roms are incorrectly reads and that causes the issue. also i notices IC15 & IC16 getting some decoding pulses from IC12 and it does the stereo decoding and having some voltage issue in SH3 pin(only 0V - no change over any tone or any function). im further checking on changing these digital chips and let you know in due course. i found all the voltages in remaining areas correct. any suggestions and guide lines are mostly welcome. my CLP550 tones getting slight distortion and at the end of the tone the distortion can here quite well and once toning period end, all noises vanished.
Dear PMP

Could you please describe in detail how you read the chip. How did you manage to unsolder them or somehow did you connect to them on the board? what application did you use. In short the whole setting.

I am not bad a diy and electronics but reading damage chip on a board would be a first for me.

I have a "dead" clp 550. I would like to extract whatever rom possible so we could compare them and make an educated choice for flashing them onto the 27040 chip

Thank you in advance for your help
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Old 03-10-2019, 03:26 PM   #91
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Hi Everyone

Thank you for the forum, I was able to resuscitate my CLP550. It is working without a glitch.

I used the the ROM from Band C with my original A chip. I believe the ROM from the A chip provided is incomplete or corrupt. I initially used it on a 27C040 however the function Piano 1 worked partially with similar symptom as without A chip.

When I used the original Yamaha chip A - everything worked without sound distortion

So far I have been unable to dump the Rom from my A chip, the universal programmer I used http://www.xgecu.com/en/TL866_main.html TL866II Plus does not support TC534000.

I requested from the manufacturer a firmware update but ... who knows when it will be available.

So if you have any suggestion on how I could dump the ROM please let me know

I am afraid that the original A chip might fail

Thanks
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Old 03-10-2019, 09:10 PM   #92
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Quote:
Originally Posted by amii27 View Post
Hi Everyone

Thank you for the forum, I was able to resuscitate my CLP550. It is working without a glitch.

I used the the ROM from Band C with my original A chip. I believe the ROM from the A chip provided is incomplete or corrupt. I initially used it on a 27C040 however the function Piano 1 worked partially with similar symptom as without A chip.

When I used the original Yamaha chip A - everything worked without sound distortion

So far I have been unable to dump the Rom from my A chip, the universal programmer I used http://www.xgecu.com/en/TL866_main.html TL866II Plus does not support TC534000.

I requested from the manufacturer a firmware update but ... who knows when it will be available.

So if you have any suggestion on how I could dump the ROM please let me know

I am afraid that the original A chip might fail

Thanks
Hi,

I checked that you can still read the TC534000 with TL866 and its software by set the software like you reading a 27C040. due to all the pinout and reading mechanisms are same, TL866 will simply read the old TC534000 without problem(and believing its reading a 27C040) and i had do that before with TL866 and successfully read my old chips(TMP534000) and contributed remaining dumps to this forum.

pls try to dump it that way and lets cross check the images of ROM-A.

Im not very clear one thing.!, Have you able to get to work your CLP-550 with given ROM dumps Fully? was your unit completely working as it intended or still having issues? if your piano working just fine, we can assume ROM dumps uploaded to this forum just fine and fit to use.

feel free to write if anything,....

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Old 03-11-2019, 12:32 PM   #93
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Hi PMD

Thank you for your suggestion I unchecked the Pin check and Verifiy ID and it worked.

Regarding the your question my CLP resurrected from the very dead :-) it is working now without distortion as a brand new.

I compared the Roms.

The Rom A you provided start with several line of FFFF. I was suspicious of it taking in consideration that when I used it, my CLP behaved like when you have no chip A

Comparing the Rom A with the one dumped showed significant difference. I can assume safely that the Rom A you provided is defective.

Rom B

The Rom B I dumped was quite short and full of FFFF, I believe the Rom B ia m providing is defective

Rom C

The Rom C i dumped was empty. I could read only FFFF.

The working combination I used

ROM A from me
ROM B C from previous first post.

PMD i would like to suggest testing the combination with the alternative Rom B you dumped. I do not have a UV eraser to do the test

Thank you everyone for the effort and patience. Nothing is impossible when we worked together From Asia to the Americas via Europe and Africa - woww!!!
Attached Files
File Type: zip Firmware CLP550.zip (373.7 KB, 9 views)
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Old 03-13-2019, 03:33 AM   #94
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Quote:
Originally Posted by amii27 View Post
Hi PMD

Thank you for your suggestion I unchecked the Pin check and Verifiy ID and it worked.

Regarding the your question my CLP resurrected from the very dead :-) it is working now without distortion as a brand new.

I compared the Roms.

The Rom A you provided start with several line of FFFF. I was suspicious of it taking in consideration that when I used it, my CLP behaved like when you have no chip A

Comparing the Rom A with the one dumped showed significant difference. I can assume safely that the Rom A you provided is defective.

Rom B

The Rom B I dumped was quite short and full of FFFF, I believe the Rom B ia m providing is defective

Rom C

The Rom C i dumped was empty. I could read only FFFF.

The working combination I used

ROM A from me
ROM B C from previous first post.

PMD i would like to suggest testing the combination with the alternative Rom B you dumped. I do not have a UV eraser to do the test

Thank you everyone for the effort and patience. Nothing is impossible when we worked together From Asia to the Americas via Europe and Africa - woww!!!


Hi Ami,

I agree with your comment on ROM-A reading is defective(not everything, to some extent) and seems your Dump was Almost perfect once compare with previous, but bit suspicions of some lines in middle. anyway i already make a copy of your ROM-A dump and will check it in a day or two and will update the forum. if anyone prefer to compare BIN files, may use HexCmp-2 from https://www.fairdell.com/hexcmp/ (using 15 day trail version).

ROM-B i coudnt recover from my case and no chance of getting comparison.
ROM-C also not recover. so i have only option of checking your A(and My A) and 2 previous recoveries. i doubt some areas of the previous recoveries also having some errors but since those are now giving satisfactory output we can safely assume those are Fit for Purpose.

will update the forum in few days.


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Old 03-13-2019, 08:24 AM   #95
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

dont the original roms have a crc32 checksum printed on them??
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Old 03-13-2019, 09:53 AM   #96
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

NO checksum printed on the chip! chip images attached
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Old 09-09-2019, 08:15 PM   #97
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Hi all,

We are in September 2019 and this topic is still going strong! :-)
Amazing efforts by the ppl from all over the planet! Thank you fellows!

Please welcome the new club member (that's me!) with the CLP-550 sound problem (most likely due to the corrupted GEW ROMs).

I was reading this thread, and noticed that there are multiple versions of the dumped ROMs in here. Let me try to put them into some system:

Let's first settle on the naming convention: I suggest that the prefix will denote the ROM number (A, B or C corresponding to IC8, IC9 and IC10), and the suffix will show the name of the dump taker/uploader. We have three of them: TabajaraLabs (aka TL), PMD (uploaded two sets, but the latter upload is fully cumulative of the earlier one) and Amii27 (aka AMI). So, for example B_PMD is a dump of ROM B, made and uploaded by PMD.

The provided dumps are therefore as follows:

B_TL and C_TL - post #65 (Page4) - there was no A_TL
A_PMD, B_PMD and C_PMD - post #88 (page 5)
A_AMI and B_AMI - post #93 (Page5) - there was no C_AMI

I have done byte-comparison of the corresponding dumps (I used the in-build comparison tool inside Total Commander, but HxD hex editor (free software) does as good of a job). Here is a brief comparison result summary:

ROM A (two versions are available):
The file A_PMD does NOT match the file A_AMI

ROM B (three versions are available):
The file B_TL matches the file B_PMD, but they do NOT match the file B_AMI

ROM C (two versions are available):
The file C_TL does NOT match the file C_PMD

Now the question is: Which combination of A_, B_, C_ hex files gives a normal operation of CLP-550? Amii27 who seems to have found the magic combo, in his post #93, wrote:
Quote:
ROM A from me
ROM B C from previous first post.
Amii27, if you still read this thread, can you pls clarify what you meant by "previous first post" and which B and C ROMs you used?

To me, that combo was A_AMI, B_TL, C_TL.
Others, please share your interpretations. Thanx.

Sorry for the longish post, but I hope it should make the things clearer for the subsequent readers who came here from the search.

Keep this thread up! :-)
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Old 09-10-2019, 09:59 AM   #98
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Hi DS,

unfortunately any combination of ROMS didnt work well with my case and i eventually giveup. i was noticed one more chip in the board not getting one input directly from sort of sterio decoder signal and output was garbled. that might be the case. but Ami conforms he had succeeded with his dump plus very first upload(TL) combinations. pls try. i order 10nos of EPROMS at very low cost and done my tests. you may re-program if needed after test. i used AM27C040-120DC ordered from ebay.

https://www.ebay.com/itm/10pcs-AM27C...72.m2749.l2649

comes fast to Sri Lanka, cheap and all working well.

also used this programmer:

https://www.ebay.com/itm/Programmer-...EAAOSwmgVdRDWS

all the best for your repair. let us know the progress or any other questions...

if need circuit diagrams, search for "service manual of CLP550" in google
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Old 09-10-2019, 06:24 PM   #99
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Thanks for your quick reply PMD,
I hope the others will re-join this conversation soon too.

Before I rush onto removing the ROMs, I want to be absolutely sure that it's one (or more) of them who is a culprit.

The symptoms in my case are not a clear cut, to this point - see below.
I do have a CRO, and can probe the signals at multiple points. Of course, I have a schematics.
Here's the brief summary - maybe someone experienced in repairing those beasts can give me their option:
- the standard check (A-1 + C7 + PowerOn) seems to be behaving as expected, the CELESTA LED is blinking (yes, it's CLP-550), all other LEDs are OFF. Though D0, G0, E0 do NOT produce any sound during the test, the B-1 key returns the piano to the normal mode.
- The Audio part seems OK (I injected (externally) the sound at the point of the analogue output of DAC, and it propagates through to the speakers just fine)
- When in normal mode (Piano1, effects=BRILLIANCE, reverb=OFF) , most of the keys do not produce any sound (I am also monitoring the DAC output with the CRO), but sometimes (randomly) something comes out as a very quiet scrambled noise (nothing like a normal note sound). What concerns me is that it's not consistent - the keypress can produce that noise once and on the next press it does nothing etc.
- I also monitor the digital serial input line to the DAC (the Clock and Frame signal inputs to DAC are both OK). Sometimes the key press produces the serial sequence at the input of the DAC (still no sound though), but sometimes there is nothing on that line when the key is pressed (no sound either, of course). I have a signal analyser, but didn't get around yet to capturing and analysing the digital stream to the input of the DAC.
- The thing I can not explain is that sometimes (not always) the keypress causes the subsequent endless continuous access to the wave ROMS (GEW1, 2, 3), which never ends. Like, I monitor #CE pins of all (or one) of the IC8, IC9, IC10, and they are clear, but when I press (and RELEASE!) the key, these #CEs go to the sequence, and it stays there forever (to me, producing the continuous wave output, although there is no sound).
Do you see such random behavior or the keys behave consistently (even though - wrongly) in your case?

The bottom line is: I'd like to do a bit more diagnostics first, just to be sure, before I jump on taking off and replacing the wave ROMs.

Thanks for your input.
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Old 09-11-2019, 03:42 AM   #100
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Default Re: Yamaha Electric Piano CLP550 no keyboard output

Hi DS, I noted, you were very observant and focus to very detailed description of the problems and behaviors of the Piano. Im certain you had the same issue of ROMs. me too getting likely issues before change ROMs. i assume ROMs had wave details of the tones also some sound effects related information's and information how to decode the bit steam to the stereo sound with some switching\multiplexing mechanism. also i guess mostly, all 3 ROMS of your Piano had issues. mainly read as zero outputs.( possibly due to disconnected pins or connections internally at silicon level), that might be some reason for endless CE as no response. in worst case it might be due to some (partial or very little)corruption in CPU ROM as well. if that was the case, i will try to send you image of system ROM dumped from my unit( i hope its still doing good).

anyway my conclusion was you are good to go with wave ROM replacement. try to remove chips very carefully, one by one without let them getting heated. remove one pin give time, remove next. once remove, read the ROM without delay(immediately) with programmer. sure you cant find correct exact chip, but select as AM27C040 and read. save each read before analyze. im telling all because my ROMs read just after removal and got some readings, but after day or two i couldn't read any of them and read as blank mostly(except some random bytes). i cooled one chip as i read only 10% of it and rest are zeros. i cooled in normal refrigerator in sealed box to about 4deg centigrade to see any improvements(that works for me in some other cases), but after that i couldnt read anything, totally no response from ROM. im glad if you can get some dumps to compare results with previous ones.

Also find attached image of the part of circuit diagram. i marked some pins with green colour boxes. pls do check those pin status while key pressed, released, ect and see its conditions and update me if possible as in my case, SH0 or SH2(one of it i couldn't exactly remember now) is at Logic Zero Always and no change what ever the condition of tones and key pressed. it should change. that will be the my problem i think as my Piano working but tones get bit distorted possible due to not decoded in correct sequence and switching not happen properly due to this pin output not changing. i feel IC12 Faulty. lets see if you can give some inputs in this case.

DAC chip not getting any issue. its bit heating but it is normal.

Good Luck!
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