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kgallen

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Everything posted by kgallen

  1. Often the titles dubbed from CDs with CD-TEXT seem to be all uppercase which I’m not keen on. So I grab the PS/2 keyboard to retitle them by hand... If I write a CD-R from iTunes to dub to MD the titles of some tracks are corrupt (don’t know if iTunes is writing bad discs or my Tascam CD section can’t read them properly) so they need reworking manually with the ‘ole PS/2 once on MD. Bit of a PITA to need to do that. Must work out one day where the issue is (not that I’m likely to be able to fix it)...
  2. With the SM that Stephen links above... The RTC (real-time clock) chip is IC3503 (S-35390A) on p34 lower-centre right. This chip is powered from STBY3.3V which is provided by the switching power supply p54 bottom centre (STBY_3.3V). If you can understand the schematics in the document then you should be able to fault find from there - check the VDD (pin 8) to VSS (pin 4) on that 8-pin chip. If you have a high impedance 'scope then XOUT on pin 2 should look like a clock (probably a sinusoid) of 32.768kHz (however the load of your scope might quench the oscillations). The chip does not have an internal battery, so the STBY3.3V rail must be used for retention too. As yet, I've not located the cell/battery/cap that supports that rail to maintain the time. Looking around the schematics, there are a fair few chips that hang off the STBY3.3V rail so the tiny 0.25uA retention supply of IC3503 could be swamped by the leakage of the other devices. So I'd expect to find some secondary supply better than a small electrolytic, i.e. like a lithium cell or similar, a super-cap at the least. Still hunting...
  3. Maybe next step to rule out damage is to extract the drive and do a careful and systematic inspection of it. Mechanical and electrical. If you have an illuminated inspection lens then all the better. Overall we’re looking for things that ‘don’t look quite right’ as we have no reference. Mechanically we’re looking for misplaced components, broken plastic or gears. On the electronics we’re looking for surface scrapes as clues, cracks in components especially small surface mount capacitors and resistors, solder joints that look stressed and PCB traces that look cracked or heaven forbit pads lifted. Looking especially around those ribbon cable connectors and areas that might be stressed. Look for shorts or bits of dirt or flakes of metal picked up from your desk. If we find nothing that is good but it’s a step we need to take to rule out issues. If you have your ‘scope, by all means use it. There are reference waveforms in the SM but whether or not any will be active if the drive can’t initialise we can’t say. But we can scope out each of the switches on the BD like limit-in and out-sw and ensure we get a logic low and high. These can be probed at the main PCB end of the ribbon cables. If you have a 2-channel scope then you can check the I2C (SCL and SDA) for appropriate activity. Again no reference for us and we don’t know what data the bus is carrying but we can look for START and STOP conditions and transitioning data bits. Here is the I2C spec if you don’t know how START and STOP are signalled on SCL/SDA. However I still think we’re looking for something more fundamental so I recommend the thorough inspection before any of that. Also vitally important are simple observations like Stephen’s idea on the Timer switch. Crazy to pull a good machine to bits only to find we had something set wrong. So if you haven’t, spend a few minutes looking around the machine in general for clues and ideas. The observation on the OWH is just the thing we’re looking for. Simple responses can indicate a lot of the circuit is working. In my job, just getting an LED lit or being able to read a chip register mean a lot of stuff is working. It's quite likely the instructions for the OWH came over the I2C from the main CPU to the BD board, so looking at the I2C for a "catastrophic fault" is probably redundant. Kevin NXP I2C Specification Look at section $3.1.1 onwards.
  4. Petter we're not at the stage yet. These are complex chips you can't simply say "stuff in will give stuff out". You don't know which chip, if any, is at fault - the level of fault finding we've done so far is nothing. Even if you could get a genuine replacement CXD2664R, unless you have a whole surface mount repair station how are you going to swap the chip without wrecking the whole board? It is not a trivial operation like replacing a socketed 8-DIP. Maybe you do have this, but there is no fault finding yet that says the DSP is bust. Why would it be unless you were very careless with static electricity precautions when you changed a belt that is on the other side of the mechanism. As an apparently knowledgeable repair tech, I'd expect you to have taken anti-static precautions during the repair. So there is no tangible reason I know of that any of the chips, or the laser, should be damaged. You've 'scoped and seen activity on the audio DAC/ADC clocks going in an out. That is good in itself but it tells us nothing about the servo side of the chip. The machine worked prior to the belt change. Look for simple problems. Conclude the main DSP chip is bad when all other simple possibilities are ruled out and based on evidence that it's not responding as it should. Sorry if that came across as a lecture, I didn't mean it to, but we can approach this in a structured way, especially given your quoted experience.
  5. As you say you’re capable, probably the best you can do is to open her up and look for a coin cell or soldered lithium battery (maybe a Panasonic ML2020 or similar) on the main board. If there is an RTC chip with integrated battery (like the old Dallas 1287) then you might be a bit more stuck.
  6. Ah he did prefix the video with "the fastest way to title without using a PC". PS/2 keyboard in the front of the machine is pretty much [*] no different to using same attached to a PC although I guess if you're entering the text into a SonicStage DB you should only ever have to enter it the once... [*] My Tascam MD-CD1 do support a few more keystrokes than my Sony MDS-E1[02] - for example Home and End work when titling. These don't do anything on the Sony which is a surprising omission by the Sony engineers.
  7. Agree Petter, getting late here too. I'll look up your IC201 then I'm probably done for today too. Good perseverance, have a good night! Kevin ETA: Oh, IC201 is the main chip (DSP), the CXD2664R. It's possible it's bust (like any other component) but I'm not there with that one yet - game over for the drive if it is (although as we've discussed on other posts, it's not fully game over if you can do without the NetMD section, as a drive from a cheap eBay 480 can get you a replacement MDM-7S1A). Not sure why you've picked on IC201 pin 15 (WRPWR). What's your thinking there? Also I'd say IC201 pins 33/34 is a bit ambitious at this point. They are the PCM connection to the D/A converter. We're not looking for an audio stream problem, we can't detect the disc and read the preamble and the TOC yet, so the audio data is a way off if we end up that deep in the mire... For my money if you're getting the 'scope out, we're looking at some control issue on the signals of the wide ribbon cable. However I don't think we have much in the way of reference material to know what to expect. The narrow ribbon cable looks more audio-side to me (see the block diagram on p39, upper right has the IC201 pins you're talking about and that is all DAC and ADC) and I don't see that we're in audio territory with this problem.
  8. Sorry C29 my typo, should have been C26. I'm looking at p20 of the Service Manual if you have it all (see link at the bottom). But actually your report is quite comforting, we're getting somewhere. At least the CPU can read the EEPROM properly. You can load (and presumably eject) a disc - is this progress from where we started? Does this mean you can get out of Standby in normal operation, or was your disc load in Service Mode. Even loading in Service Mode gives us some info. Can you confirm if the disc load eject was in Service Mode or normal mode, and if normal if you are able to exit and enter Standby now? Can you go back to C12 and step through to C26 and report if the results were OK or NG (no good). You can summarise the exceptions rather than write them all out. Baby steps but it feels like we have a little data to work with. I'm with Stephen though, I'm still thinking cables. I've just not put my finger on where and how yet... If you happen to have some isopropyl alcohol (and some cotton buds/Q-tips), maybe you could clean the contacts on the FFC (ribbon cables) at both ends and in the sockets on the PCBs. Let them dry a few minutes before reassembling. MDS-JB980 Service Manual
  9. Well all credit to you for persevering and getting it working - that's quite an achievement given the state of that OWH at one point! To echo what you said, the input, photos and videos from @jonathanpotato have been outstanding. Just for the fact of saving another MD machine and getting it back into service for it's owner is pleasure for us all! Now, anyone fancy helping out on the 980 thread, we're still struggling with this one today! Hope you're all staying safe and will be back on SIF soon - for the right reasons! Kevin
  10. Yes, the CPU is alive and well. Just not talking to the BD :-D Sorry, maybe I should have said...! By the way, if you're trying to find the CPU and it's related infrastructure, you can't see it. Most of it is on the underside of the main PCB. The only stuff on the top is the connectors (internal and external), the power supply (top left), the coax/optical SPDIF drivers and the analogue audio output stage (top right) - with a smattering of (Nichicon?) gold caps I see from the photos... (The little green daughterboard top centre is the USB -add-on for NetMD. Sony seem to call this chip, CXD1873R, the Unicorn...)
  11. Just looking at the SM block diagram, it dawned on me that the loading motor is completely unrelated to the remaining disc mechanisms (laser, servo, audio path). It's driven directly from the main PCB CPU (even the motor drive chip is on the main PCB). It's two pins on the large ribbon cable (LD-OUT/LD-IN, pins 26/27). There will be the loading switch contacts too (OUT-SW, pin 16, goes logic low when no disc in - remember playing with this on my MDS-E10). But even if the rest of the drive was unresponsive, that's the sort of thing that could still work. But I think at this point it's not? Of course if the CPU has not managed to successfully talk to the BD then it will probably refuse to do anything with it.
  12. (Stephen there is no narration on the video). I looked in the 980 and 480 SMs and can find no details of what is in the INFORMATION (C31) section. I'll look in some more... Is the drive fully back in the machine? Can you do: C18 (VERIFYMODE) -> will check the EEPROM C29 (Iop Read) C34 (CPLAY1MODE) can you use [YES] to move the sled MID/OUT/IN (the numbers on the display are useful here if anything useful happens) -> Need a recorded disc in for this one. Actually in CHECK mode you can do C12 thru C27. I'm not sure it tells us much but getting "OK" values back would be comforting! Admittedly there is not much above that gets us much further than what we think we already know. Just scratching around in the dirt for clues... Note: There are no warnings in the 480 SM regards IC195 as there are in the 980 SM. So as Stephen suggests, there must be a DRM code included in there for the NetMD machines - 480 is not NetMD.
  13. I think we’re looking at a simple (ha ha ha) drive issue. USB is probably off track - but of course any ideas are good even to just stimulate thoughts and keep us talking. No bright ideas from me at the moment. Might pull my 480 out of the shed later and pull it about a bit - it’s a cost reduced version of your 980. Kevin (Stephen has too much faith in us and not enough on his own worthy suggestions)
  14. I'm pretty sure that message refers to the EEPROM on the drive with the laser diode characteristics. The part for DRM would be more like a fixed MAC address I suspect.
  15. Sort of, but it can't do it. Whilst the EEPROM SDA/SCL (I2C/IIC) signals are on the wide ribbon there is no power. So the CPU can't read the EEPROM, but similarly without the narrow ribbon inserted there is no power to write the EEPROM. But please don't try it, input clamping diodes on chips can sometimes provide enough power via the input signals to operate the chip marginally (as an aside, that's apparently how the ARM CPU was accidentally discovered to be a "low power" design - they forgot to wire up the power pins, but the first chips still "operated" through the current available through the input diodes from sufficient input signals at "logic high".).
  16. According to the schematic, the long ribbon doesn't carry any power (there is one D-GND). It seems to have most of the "low activity" signals like switches and the EEPROM. All of the power comes in on the smaller ribbon plus many of the servo signals. Plenty of GNDs on the narrow ribbon with those fast signals which is what you need...
  17. The voltages you measured, where did you probe those? With the drive out and upside down I can see this is possible with care, probing on the underside of the drive PCB (I see you have schematics on your desk). Where are you probing the 0V when taking these measurements - on the drive too? But I take the drive is getting the required supply rails and they are in spec. For confirmation, if you disconnect the drive ribbons, does the Iop get reported in SM? (Trying to demonstrate the CPU is accessing the drive rather than pulling cached figures from RAM).
  18. If you're in "Standby", will it take a disc in? (Probably not, but I'm just wondering how the mechanics of the drive are "sitting" at the moment.). If you're in service mode, can you go to the Check item that reads the Iop value? This requires the main PCB CPU to access the EEPROM on the drive. From recent comments it seems the drive is "dead" (as in unresponsive rather than broken). We need to start narrowing down if it's getting any power (+5V and +3.3V rails) or whether the main PCB CPU is just not seeing the drive at all.
  19. I think the C13s are benign. The belt is too sloppy to eject or mount the disc properly. On a failed insert I've never seen the laser sled actually try to read the disc, I think the electrical and mechanical interlock mechanisms are too mature by this version of the MDM. So I don't believe any mechanical damage or stress will have occurred. I don't hear any mechanical torture going on in that video and I've had much worse (the "machine gun") with some of my machines and the drives have suffered no lasting damage. The machine is pulling the disc back in because it has passed the threshold where the machine thinks the disc is out, then the disc sitting there creates a new insert detect so it pulls it back in. I had the same with pretty much all of those machines (440, 480, E10) I bought with "faulty loading" where it just needed a new belt. I still feel at this point we're looking for a simple explanation - even if that is eluding us for now! Do no damage at this point looking for anything complex. On which note, is that drive properly back together yet even if it's not mounted in the machine? ETA - I have had the same as the video where you can't trigger an eject every time. Actually that was common on my 530 which ended up being oxidised ribbon cables in the end (remember those days Stephen, that's how you hooked me into this Forum! :-D )
  20. At this point I break for a cup of tea in a different room and let the sequence of events mull over in my mind for 10 minutes. Then I go back and have a fresh look.
  21. That's not crazy, that's brilliant and inspired! (In one of the early photos it can be seen in the OFF (centre) position).
  22. OK great Petter, thanks. Myself I would be tempted to rewind here. I'm not sure we need to take this machine apart so much given what we should have performed initially. We shouldn't be looking for a complex fault. We know we had a perfectly working machine prior to the belt change. We did a simple repair action to replace the belt with one of a similar size and thickness. The new belt is not fouling the adjacent rack gear. We reassemble the drive with the spring to the left and the retainer slide engaged at the rear. Both pivot pins at the front are engaged correctly. If disconnected, we reconnect the pair of ribbon cables to the drive end, ensuring the ribbon contacts mate with the socket contacts and they are fully inserted 'square'. We mount the drive to the chassis, ensuring the 4 bushes are the correct way round to set the drive height correct for the loading slot. We have 4 shouldered machine screws to mount the drive. We ensure any flying earth leads connected to the drive are connected to the chassis. We ensure the ribbon cables at the main PCB end are inserted fully and square. We reconnect mains power and press standby. The machine possibly flashes "Initialise" and the drive settles to an idle position. We have a repaired machine. So, which step went wrong for us? Were other actions performed that changed the situation and can help us repair this "remotely"? The pictures are a great help, but I don't at this point see anything amiss with what I see. I don't have this machine myself but I have several (many!) with this (MDM7-series) drive, that I've replaced the belt on (440, 480, E10, E12). My machines all have comparable internal layouts to this one. (Edit to correct Petter's name, sorry!)
  23. Actually at this point I really need to point out you need to be REALLY CAREFUL OF THE LASER OUTPUT. You have so much of the top of the drive off, there may be an interlock to stop the laser coming on. But there might not be and if you fire this thing up and look at the laser you WILL BE BLINDED. You cannot see the laser light, it is invisible, even whilst you have your sight. EXTREME CAUTION!!! No more comments from me until I know you've seen this warning.
  24. I'm not convinced the wide long ribbon cable is the right way around in the green connector on the main motherboard - from the second photo on your post a few back. Looks to me like the blue plastic stiffener is on the side where the spring contacts are. All ribbon cables, make sure the exposed contacts on the cable are on the side the spring contacts are exposed in the female connector on the PCB. I can see on the short cable that it is the correct way round on the main PCB. Check the others are similarly oriented in the socket. It's a bit hard to be sure from the photos.
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