Jump to content

Oh no!


XW-Addict

Recommended Posts

XW-perfrom a factory reset, sounds like something with the programming internally may have temporarily "glitched". There is no internal memory battery in these so that can't be it (low internal batteries can do this). And if you have batteries in your XW take them out and power up with just the adapter. If the D batteries are getting low this can also cause problems.

Link to comment
Share on other sites

On 10-9-2016 at 3:59 PM, Jokeyman123 said:

XW-perfrom a factory reset, sounds like something with the programming internally may have temporarily "glitched". There is no internal memory battery in these so that can't be it (low internal batteries can do this). And if you have batteries in your XW take them out and power up with just the adapter. If the D batteries are getting low this can also cause problems.

 

Found out its the step sequencer doing for one, The buttons probably got stuck and making contact constantly but something else is interrupting

changing octave transpose and tap tempo as well. I`ll do a full factory reset first to be on the sure side. 

  • Like 1
Link to comment
Share on other sites

Another little weirdness I had overlooked-when you are playing along with a sequence-if you want to transpose live from the lower keys while playing-you need to be in 'sequencer" mode both from the middle section of the XW-where you select tone, sequence or performance-but you must also select "sequencer" from the left side of the panel-where it specifies drawbar organ, solo synth, hex layer etc. I think I need to spend more time learning this XW. i thought I was pretty good with it, but it is amazing how fast one can switch around to almost anything from anywhere if you know how. and only recently noticed that the cutoff filter as many have already mentioned, could be better, is probably only 4 or 8 bits and is pretty rough with slow sweeps. Hmmm.......I wonder if i could hack this to smooth it out-I'll have to poke around keyboard hackers to see if this has been accomplished with other brand keyboards/filters that had this problem, i seem to recall Casio is not unique in this respect. i know capacitors can smooth out a stepping filter's respone, but whether this can be accomplished with the XW, not sure (yet). I think I'll post this as a new post for the XW since it's getting off ytour topic XW, sorry!

  • Like 1
Link to comment
Share on other sites

4 hours ago, Jokeyman123 said:

Another little weirdness I had overlooked-when you are playing along with a sequence-if you want to transpose live from the lower keys while playing-you need to be in 'sequencer" mode both from the middle section of the XW-where you select tone, sequence or performance-but you must also select "sequencer" from the left side of the panel-where it specifies drawbar organ, solo synth, hex layer etc. I think I need to spend more time learning this XW. i thought I was pretty good with it, but it is amazing how fast one can switch around to almost anything from anywhere if you know how. and only recently noticed that the cutoff filter as many have already mentioned, could be better, is probably only 4 or 8 bits and is pretty rough with slow sweeps. Hmmm.......I wonder if i could hack this to smooth it out-I'll have to poke around keyboard hackers to see if this has been accomplished with other brand keyboards/filters that had this problem, i seem to recall Casio is not unique in this respect. i know capacitors can smooth out a stepping filter's respone, but whether this can be accomplished with the XW, not sure (yet). I think I'll post this as a new post for the XW since it's getting off ytour topic XW, sorry!

 

No problem, Resetting resolved a quarter of the problem. I'll need to open it up to see if dust have gathered on a weird spot. 

It is interesting to find out how much can be poke around in the XW, There is one person also like you savvy enough to roam 

in the keyboard but I forgot his name. 

Link to comment
Share on other sites

You are savvy enough, I always enjoy your posts! And might be thinking of Ted (Tnicoson) or AlenK. Too bad we can't all get together someday and meet with Mike Martin-have a sitdown roundtable discussion/brainstorm just for coffee and giggles :banana:

 

If you need any help taking apart the XW, lt me know, I've done it twice (yes blew my warranty awhile ago....) The center section hinges up first from taking screws out the bottom. Then the 2 outer sections come out but there are screws hidden inside the center section that need to be removed to hinge out the 2 end sections with the rubber pad thing and the left control panel. Actually pretty simple if you've taken any other keyboards apart to see the squirrels running around inside  :P

Link to comment
Share on other sites

I have never opened up my XW-P1. Thankfully, I haven't had any problems with it (here's knocking on wood), probably because I purchased an extended warranty when I bought it (it was very inexpensive). In my experience that almost always protects a piece of equipment because of the maximum perversity of the Universe. :D  

Link to comment
Share on other sites

I wouldn't mind a cup of tea and biscuit heck lets go straight to a cold one. 

I've opened it once already because liquid got spilled on the key's ones 

and I was curious about the inside of the XW anyway. Which is pretty modular if I 

have to say so, Would be pretty darned to circuit bend this one if anyone would so.

 

I've browsed through the forum historical list and found old posts, Cyberyogi also 

belongs to the list of savvy's he really delves inside of it like a pro. 

 

 

Link to comment
Share on other sites

  • 3 months later...

I haven't seen the guts of modern Casios yet, but I expect that XW series is mostly a softsynth on a chip (although patents mention existence of some dedicated sound generator hardware; the SA-series microcontroller did only bit-banging of computed waveforms through a DAC). I bet a wheelbarrow load of rotten watermelons that there are no analogue VCF chips inside. That era is over since HT-6000. May be a software mod can do this (the thing takes firmware upgrades), but likely the algorithms internal resolutions are too low and even I know nothing about the type of microcontroller.

Casio XW-G1 is a cool thing (I have none, but it sounds like a dozen of C64 SID chips made into a synth) but certainly not hifi. Maybe that a 5€ Raspberry Pi Zero has the computing power to emulate the whole thing; that's why Casio used "hybrid" (soft- and hardware) sound generators at all (to complicate hardware piracy and obfuscate how the software works). XW-P1 is to me a bit too much a wannabe workstation (hey, Yamaha MK-100 was even more lofi and still fun to play) so I would prefer the G1. Casio only should remake it in MicroKorg (or Casio MT-series) size case with built-in speaker.

Link to comment
Share on other sites

Of course there are no VCF chips in the XW synths! No one will take your bet. As for how much of the functionality is accomplished using dedicated hardware and how much is done with software, only Casio can say. The main chip is encapsulated on the PCB (there's a photo of the board somewhere on the forum). Go ahead, buy a P1 or G1 and pry it off to see what's underneath. Of course you won't learn anything useful. I can say with confidence the fact that it's encapsulated means it isn't an off-the-shelf part. I am willing to guess that it's a custom chip Casio designed originally for their WK/CTK series of instruments.

 

Some of the features added to the XW may use a lot of software (like the solo synth), others like the Hex Layer mode and even the drawbar organ mode may use less software. All the synthesis modes are likely augmenting and using in particular ways some underlying hardware on the chip such as, say, dedicated sample playback DMA channels. 

  • Like 1
Link to comment
Share on other sites

I found no such picture anywhere (not even Google), but I seriously doubt that Casio "encapsulates" chips to enshroud what is inside. The only consumer product I saw something encapsulated inside was my TechniSat cable TV receiver, which contains a rectangular block of black epoxy resin casted into a plastic frame around a PCB section to prevent non-destructive access to the pay TV decoder circuitry. And this rather suggests that in opposite the sealed block contains documented standard parts (e.g. standard microcontroller) they want to lock away from hackers. Pinouts of my 1980/90th Casio keyboard sound ICs and single-chip CPUs don't match anything commonly known and thus are very likely custom ICs anyway.

What you likely mean is a COB IC, which tells not more about the chip (and potentially suspected security paranoia) than that it has low power consumption (needs no heatsink) and can be reliably mass produced in huge enough quantities to justify making it cheaper by directly bonding it to a PCB. The low power constraint however means that it certainly contains no cutting edge ultra high performance general purpose CPU. ("Raspberry Pi Zero" is a good example how fast such an uncooled chip may be. With specialized hardware it may need even less power to do audio processing.) A related Casio patent (about integrating a main CPU with several audio LSI cores into one chip) may be US5541360 of 1996 (with priority dates going back to 1992).

On this page I found a small photo of the inside of the XW blob:
XW-heart-HPSS-Chip.jpg

http://www.casio-music.com/de/instrumente/technical-insights/xw-technologie/


Here is an excerpt from my WarrantyVoid FAQ:

about COB ("black blob") ICs:

Did you ever wonder why ICs in modern toys and consumer devices are often welded in a black blob of plastic directly to the PCB? It is a false myth that the blob of such COB (chip on board) ICs serves the purpose to prevent commercial espionage by hiding the circuit inside. In reality it is simply cheaper to mount the silicon die of a chip directly to a small PCB (so far it needs no heat sink) than to package it inside a rectangular plastic or ceramic case and then solder its legs to the PCB. The plastic blob protects the die against corrosion and mechanical damage, and the blob is not black to enshroud the interior against spectators but to shield it against light, which would otherwise generate electricity in the silicone (like with solar cells) that prevents proper working. (Despite this I even found white blobs in certain toy keyboards.)

Particularly with some old COB ICs the blob was made instead from hard plastic resin from soft silicone rubber. Be very careful not to scratch or tear such coatings, because it may easily destroy the chip or its fragile bond wires. Do not use silicone oil near these; it may dissolve the rubber over time and so weaken the seal. Also be generally careful not to burn the blob with a soldering iron. In some old handheld electronic games I even found bare microchips without blob, those were only protected by a hollow hard plastic cap that was bolted to the PCB; by the lack of corrosion protection the life span of such ICs is very questionable. I own an LCD game which has a hole in that cap (production fault) and continuously crashes.

about unlabelled & camouflage ICs:

In music keyboards and other devices sometimes there are ICs without printed type number. Often it is sanded off but may be also painted over and sometimes additionally stamped over with a short internal name. Obvious purpose of this can be to make hardware piracy difficult (like with Wersi organ kit ICs). But especially in cheap noname hardware it can mean that it was build from cheap rejected name brand ICs (e.g. Yamaha sound chips in a Medeli tablehooter) those failed the quality check (e.g. function only at 900kHz instead of the rated 1MHz) and so were debranded by the IC manufacturer in the fear of spoiling their brand name with substandard parts.

Another explanation is that these even may be re-branded scrap parts. I saw a TV docu that poor people in China and 3rd world countries recycle e-waste by desoldering electronic components (often causing heat-damaged by primitive methods like blowtorch or coal fire) to bulk-sell them untested. To make more money, criminals then often print fake new labels on and ship them to the industry as counterfeit new parts (often faulty or wrong types those can be a safety hazard). I don't know if also music keyboard ICs are affected.

A sanded off type number often can be made readable by wiping a drop of water or silicone oil on the surface and shining on it with an LED lamp at a flat angle. A digicam helps to enlarge details.

Particularly COB, but also other custom ICs were often released in several different package variants (e.g. to fit on different PCBs or to enshroud what they are based on). While the silicon die stays the same, packages can have unused pins omitted or for configuration internally bonded to nearby pins ("bonding options"). Also one of the supply voltage inputs (negative, 0V or positive) often covers the whole bottom of the die; so this pin may be placed anywhere (also as multiple pins among others). Packages that are too large for a particular die sometimes have many pins (often every n-th pin) internally not connected; such NC pins will show high resistance (also in diode test mode) in both directions against all others. Additional pins may be also internally connected to their neighbours. (E.g. FM sound ICs in Chinese keyboards had many additional NC pins to distract from that they were copies of much smaller Yamaha sound ICs. But even Yamaha himself proudly created a "16 pin" sound IC YM3427 with 8 of its pins NC.) To identify camouflage IC variants, it is most important to know that despite possibility of omitting or inserting blank or duplicate pins, the pin order will stay the same (at least unless the die was redesigned too, or a complicated adapter built into the package). Regard that the placement of pin 1 still may differ when the die was installed rotated or the numbering was changed. So it can be a good idea to compare the actual order of function pins around the chip rather than their absolute positions. (Of course this tip is only valid for classic ICs with pin rows along their rims, not modern packages (like BGA or Pentium CPUs) with hundreds of contacts covering their entire bottom.) With COB the pins typically count anticlockwise when looking at the blob side.

Link to comment
Share on other sites

Thanks for the lesson. By "encapsulated" I did indeed mean COB. Encapsulated is still a valid word in this context but not, I agree, specific enough in this case. I did not mean to imply that Casio was trying to hide anything. They may be protecting against industrial espionage (you flatter yourself if you think they care about what circuit benders do) but far more likely it is done merely for cost, as you say. That is one of the reasons I said it's probably a custom chip of some kind; because they would surely put one of their own chips on the board that way. Another, better, reason to think it's a custom chip, with certain operations done with hardware and not just code, is that there are particular unusual aspects of the operation of the XW synths that tell me it shares the same functional constraints as the last series of WK/CTK instruments. If it was just all software they could have changed those. Those aspects have remained unchanged throughout firmware updates and Mike Martin has stated here for a couple of them that hardware limitations are the reason. I'll take him at his word. 

 

BTW, here is the post in the Casio Music Forums with the picture you couldn't find.   

 

CYBERYOGI, I gotta ask: Why do you post about the XW synths in the Casio Music Forums? You have said you don't own either model yet you speculate about what is inside them based on no real, specific information about them (only much older models you have analyzed) or even based on experience using them, and from my perspective in a faintly disparaging way. Your profile says " I collect small and strange music keyboards and partly build synths from them. I detailed research 1980th Casio home keyboard hardware." That's great, but have you designed embedded hardware for any commercial products? Written any embedded software that we can find in commercial products? (Coding on something like a Raspberry Pi for use in a one-off creation doesn't really count in my book.) If not, then I will take your speculations about how Casio designs their products today (not in the 80's or 90's) with a grain of salt. Buy and actually use an XW synth and I will start to take what you say about them in particular more seriously. 

Link to comment
Share on other sites

Thanks for the link. With "encapsulated" I thought of "potted". Here is what real potted hardware means.

Look at this 1970th speech synthesizer and what an archeological excavation task it was to document the inside.
http://www.kevtris.org/Projects/votraxml1/
another model:
http://kevtris.org/Projects/votraxpss/unpot.html

But my Atari 800XL power supply indeed was potted too (likely to improve heat distribution, but may be planned obsolescence), so in 1980th I had to build a new one from a kit when the overheating thing failed.

I have not coded for Casio and yet own no XW synth (very little space left and mainly interested in older stuff, but may indeed buy an XW-G1 or the small XW-PD1 tekkno groovebox if it is sufficiently editable through a PC app). But I am interesting in technical similarities (e.g. CTK-1000 is obvious audible related to the classic SA-series sound engine). I am not solely into sound toys, but also own some big stuff (e.g. a Vermona SK86). The XW-G1 has that strange chiptune appeal (much more resembling C64 SID than e.g. Minimoog) that I like.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.