Guest rasteri Posted August 18, 2016 Share Posted August 18, 2016 (broken off from the PT-01 scratch thread to keep things on topic) So I want to see how far I can get with reverse-engineering and hopefully modding the CDX. I always wanted one of these things but the limitations put me off. Ideal endgame would be to ditch the CD drive and give it CDJ-style USB stick support, although if we can properly crack the firmware then essentially we can add any feature we want.Some interesting things :The CDX's main control software is run on a pic18F8720 which is a chip I'm very familiar with and will be easy to mod.The MP3 decoder chip (ML1201E) in the CDX actually already has USB support, but there doesn't seem to be any information about it on the net. However I bet it's actually just a rebadged off-the-shelf chip that we can find a datasheet for if we look hard enough. I NOW RECKON IT'S AN FPGA, SO USB SUPPORT MIGHT BE MUCH HARDER. The PIC firmware will likely need to be modified but that is very doable as discussed.I've started reverse-engineering the .wav-based firmware update format, some notes here : https://docs.google.com/document/d/1rS7EIAJpvYFkpBIV-T-TNYLXAQGC4se6yvexYDsOwJ8/edit?usp=sharingThe HDX firmware actually contains the unencrypted raw binary files and I think uses the same chipset as the CDX, so that might give us some more clues - https://www.numark.com/images/product_downloads/hdx_v118_00.zipI don't have a CDX yet but Flexinoodle is kindly providing a broken one. Once I get that I can start hooking it up to a logic analyser and really get down to business. 3 Quote Link to comment Share on other sites More sharing options...
Guest Symatic Posted August 18, 2016 Share Posted August 18, 2016 shits bout to go down Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted August 18, 2016 Share Posted August 18, 2016 There are four other major chips beside the PIC that I can see -Motorola XC56309GC100 - This is a DSP that presumably handles the audio pitch and effects etcML1201E - Some kind of MP3 decoder chip I think it's an FPGASony CXD3068Q - This is a fairly standard CD drive controller/Servo controllerTexas Instruments TMS320LF2407A - This is being used as the motor controller Of those I'm most interested in the ML1201E since it's the one we'll need to know about to add USB support. I'm not really interested in adding effects or changing the way the motor operates so I don't care about the DSPs, and the CD drive controller is something we hopefully won't even need anymore (although perhaps emulating it would be another route to adding USB support if our attempts to find out about the mp3 decoder fail). 1 Quote Link to comment Share on other sites More sharing options...
DJ Rock Well Posted August 18, 2016 Share Posted August 18, 2016 As usual, I know nothing but bow to your dominance! Seriously, if you could make it possible to get a cheap CDX working well and off a USB stick at that, I'd definitely be on the lookout for one.As usual, I know nothing but bow to your dominance! Seriously, if you could make it possible to get a cheap CDX working well and off a USB stick at that, I'd definitely be on the lookout for one. 2 Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted August 18, 2016 Share Posted August 18, 2016 Yeah me too, haha. BTW I'm now 99% sure the ML1201E is an FPGA, given that it requires a separate 2.5v core supply, has an external ROM chip, and interfaces directly with some SRAM. Quote Link to comment Share on other sites More sharing options...
DJ Rock Well Posted August 18, 2016 Share Posted August 18, 2016 My thing is, I have DVS and I can set up the A6 with my laptop to play beats and record samples in Maschine and run Traktor for the DVS. I have to use a little mini mixing desk for monitoring though and if it's set up at home it's a bit of a ball ache to keep moving about. If I could have a CDX sat at the studio ready to go though, it would be great for quickly recording cuts for beats I'm working on. Quote Link to comment Share on other sites More sharing options...
Mutis Mayfield Posted August 18, 2016 Share Posted August 18, 2016 Great Rasteri! My humble opinion if it's possible to implement usb read an easy way it could value the effort but if not then hack it directly into something new like your scratcher is the way to go. Said that I will love to thumb drive and portablist mod. How can I help? 1 Quote Link to comment Share on other sites More sharing options...
djdiggla Posted August 18, 2016 Share Posted August 18, 2016 While ur at it fix the shit drift issue in vinyl mode. Aside from that I fucking loved my CDX. What a POS tho. Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted August 19, 2016 Share Posted August 19, 2016 My humble opinion if it's possible to implement usb read an easy way it could value the effort but if not then hack it directly into something new like your scratcher is the way to go. Yeah at the end of the day we can perhaps just gut the internals and replace them with a raspberry pi or something. But as the CDX already has the ability to do 99% of what we want it'd be a shame to have to chuck it all away. Said that I will love to thumb drive and portablist mod. How can I help? You got a logic analyser? I'd love to see what sort of shit the PIC and other components are saying to each other 1 Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted August 19, 2016 Share Posted August 19, 2016 There is also an NXP 89C58 that seems to be multiplexing the control surfaces (buttons, LCD etc) to the PIC/DSP. Also I think the PIC might actually be doing a lot less than I previously thought. Quote Link to comment Share on other sites More sharing options...
Mutis Mayfield Posted August 19, 2016 Share Posted August 19, 2016 (edited) I will ask Norbert if he wants to put some time... At this moment I only have an old oscilloscope, it could help? I didn't use it never... As a reverse engineer my last step will be study ohm's law I supose :V Some pornhttps://instagram.com/p/BJSuPuqhb9r Edited August 19, 2016 by Mutis Mayfield Quote Link to comment Share on other sites More sharing options...
arkei Posted August 22, 2016 Share Posted August 22, 2016 I got a faulty CDX lying around. Exchanged the CD-Drive once, but that didn't hold up long :-( Other than that it was really a good piece of gear... 1 Quote Link to comment Share on other sites More sharing options...
Flexinoodle Posted August 22, 2016 Share Posted August 22, 2016 Rasteri will have his CDX in a few days, i just have to wait till im off work so i can send it 1 Quote Link to comment Share on other sites More sharing options...
ericuk Posted August 27, 2016 Share Posted August 27, 2016 I'll be watching this thread! I have a cdx just waiting for this!!!! #jizz#giveyouallmymoney#cdxboner#fingerscrossed#byebyetodirtyrecords 3 Quote Link to comment Share on other sites More sharing options...
Holby Posted September 23, 2016 Share Posted September 23, 2016 Picked a faulty one off ebay for peanuts...it was only the ribbbon to CD drive twisted...all good now...would love it with USB.. Quote Link to comment Share on other sites More sharing options...
Flexinoodle Posted September 23, 2016 Share Posted September 23, 2016 Just a wee update, the one i sent Rasteri had a burnt out chip, he replaced that and now has a working jam, so he is on it 2 Quote Link to comment Share on other sites More sharing options...
Mutis Mayfield Posted September 24, 2016 Share Posted September 24, 2016 I could try to open mine with a friend and check anything you need too. Just waiting instructions... Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted September 24, 2016 Share Posted September 24, 2016 I'm waiting for my logic analyzer to arrive so I can do proper reverse engineering, but I've been slowly building up notes and ideas on the google document I posted earlier. Don't expect anything soon though, time and effort constraints mean it'll be an on-and-off job. 1 Quote Link to comment Share on other sites More sharing options...
Mutis Mayfield Posted September 24, 2016 Share Posted September 24, 2016 (edited) Mine is collecting dust and I purchased for 50 with driver board broken. I changed it for another one (the cdx from the video) and come alive again. Cd drive no luck. At service notes talk about changing some resistences to improve motor driver burn and about how to dare with data cable error too. I have also the pinout for solder cable directly avoiding flat one (and even the part solded by Norbert from the old cdx too) Anyways if I can bring it to life it will worth the effort but if not, raspi and new ideas are calling me. My luck is I'm starting a makerspace in my area with some friends and I have new tools (like digital oscilloscopes) to work on my projects. I hope my friends also help me with raspi mesh and start tinkering on all this idea sometime. All the resources collected over years (including hdx firmware?)https://drive.google.com/open?id=0B4ftWaZ6ARSUVEF5R3dseFY4Tmc Edited September 24, 2016 by Mutis Mayfield Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted September 24, 2016 Share Posted September 24, 2016 Ebay claims CD drives are rare but it's bullshit, the servo mechanism (the bit that normally breaks) is actually a totally standard one you can still buy new from places like CPC for a tenner or so. I think this is the correct one : http://cpc.farnell.com/unbranded/31155/ksm213ccm-cd-pick-upmech/dp/AS00201 - I'll double check when I go to the shop today. 1 Quote Link to comment Share on other sites More sharing options...
Mutis Mayfield Posted September 24, 2016 Share Posted September 24, 2016 (edited) I was talking about this:https://instagram.com/p/BKvlRA6D58q The drive itself works time to time but doesn't "read" and it could be due the lens or (it seems) some kind of data corruption for the bad connection on flat cable. Edited September 24, 2016 by Mutis Mayfield Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted September 24, 2016 Share Posted September 24, 2016 OH ok - I had the same problem on my CDX but the flat flex cable was fine, I checked all the conductors. Turned out to be a fucked servo. 1 Quote Link to comment Share on other sites More sharing options...
Flexinoodle Posted September 24, 2016 Share Posted September 24, 2016 I think your second one is the cd cable dude, when you make a new cable, make 3 for me haha 1 Quote Link to comment Share on other sites More sharing options...
Guest rasteri Posted September 24, 2016 Share Posted September 24, 2016 Replacement 32-way flat flex cables will be dirt cheap, I'll find you a part number when I get a chance to measure the pitch. TBH a better long term solution might be to replace the FFC with a ribbon cable, then it'd never break. I think that's what later CDXs did. 1 Quote Link to comment Share on other sites More sharing options...
Mutis Mayfield Posted September 24, 2016 Share Posted September 24, 2016 (edited) Replacement 32-way flat flex cables will be dirt cheap, I'll find you a part number when I get a chance to measure the pitch.TBH a better long term solution might be to replace the FFC with a ribbon cable, then it'd never break. I think that's what later CDXs did.Yup also Norbert did it with my old. In the google drive there is the pinout for the scsi connector Edited September 25, 2016 by Mutis Mayfield Quote Link to comment Share on other sites More sharing options...
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