blingy Posted March 12, 2013 Report Share Posted March 12, 2013 My Midibox Seq V4L is complete and beautiful. It works brilliantly. Now I want to mess up it's MIDI beauty by adding din sync in order to sync it's insanity with certain Roland devices. If I'm reading MBSEQ_HW.V4L correctly with LPC17 as my core, by default it should output clock to J28.SDA and start/stop to J28.SC. If my understanding of din sync is correct (and this could be where things go awry), J28.SC should give me +5v as long as the pattern is playing. I don't have a scope handy so I'm trying to test this with a multimeter. I'm not getting any voltage on J28.SC or P2.11 on the Xpresso board even when the pattern is playing. Either I'm misunderstanding how din sync works or I'm missing a step here. I'm still waiting for a sd card in the mail so I'm working from the default configuration at the moment. Any insight would be helpful. Thanks! Quote Link to comment Share on other sites More sharing options...
Altitude Posted March 12, 2013 Report Share Posted March 12, 2013 (edited) You need to buffer and level shift the signal up. The LPC core is 3.3V, DINSYNC needs 5V http://ucapps.de/mbhp/mbhp_core_lpc17_output_buffers.pdf Edited March 12, 2013 by Altitude Quote Link to comment Share on other sites More sharing options...
blingy Posted March 12, 2013 Author Report Share Posted March 12, 2013 That makes sense...I guess I misinterpreted the documentation: ################################################## # CV and Gate/Trigger/Sync Setup ################################################## # AOUT interface now selected in CV Configuration Menu and stored in MBSEQ_GC.V4T file # please scroll through the menu to find this page! # should J5A/B/C outputs be enabled (0: no, 1: yes, 2: yes, but in open drain mode)? # - the 6 first AOUT gates will be forwarded to J5A/B # - the remaining last 2 AOUT gates are available at J5C.A10 and J5C.A11 (LPC17: J28.WS and J28.MCLK) # - DIN sync clock will be forwarded to J5C:A0 (LPC17: J28.SDA) # - DIN sync start/stop will be forwarded to J5C:A1 (LPC17: J28.SC) # - if open drain mode enabled (option 2), external pull-ups have to be connected to J5 pins # (advantage: pin levels can be pulled to 5V) # # NEVER USE THIS TOGETHER WITH ANALOG POTS - IT WILL CAUSE A SHORT CIRCUIT! That said I still should be getting 3.3V on J28.SC, no? Quote Link to comment Share on other sites More sharing options...
Altitude Posted March 12, 2013 Report Share Posted March 12, 2013 (edited) Yeah, you should see pulses, Dont think a meter will cut it though. You'll need a scope. This should work out of the box.. You can try a soundcard scope like this: http://www.zeitnitz.de/Christian/scope_en Edited March 12, 2013 by Altitude Quote Link to comment Share on other sites More sharing options...
blingy Posted March 13, 2013 Author Report Share Posted March 13, 2013 I think the pulses would be on the clock pin, not the start/stop pin. Quote Link to comment Share on other sites More sharing options...
Altitude Posted March 16, 2013 Report Share Posted March 16, 2013 yes, of course. That's what I thought you were measuring.. IIRC, start/stop is a pulse as well though.. Quote Link to comment Share on other sites More sharing options...
TK. Posted March 16, 2013 Report Share Posted March 16, 2013 No, the documentation is correct: with "J5_ENABLED 1" the clock pulse is available at J28.SDA, and the start/stop signal is available at J28.SC Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
blingy Posted February 25, 2014 Author Report Share Posted February 25, 2014 Is there a setting somewhere for the PPQN? I have added a level shifter but it's still not running at the same tempo. Slowing down the tempo slows the instrument receiving the sync, but it's not quite lined up. More testing to be done tonight and I will post some pictures of my level shifter. Thanks. Quote Link to comment Share on other sites More sharing options...
blingy Posted February 26, 2014 Author Report Share Posted February 26, 2014 OK I don't think it's a PPQN setting, I think the voltage coming from IC6 isn't actually +5v on my build. So I'm only level shifting it up to about +4.7v and my 303 is quite picky about getting +5v on the clock pulses. Even when I power the midibox from a laptop it only gets up to about +4.9v. Any ideas? Maybe I just need to build a power adapter to get din sync out. Quote Link to comment Share on other sites More sharing options...
TK. Posted March 2, 2014 Report Share Posted March 2, 2014 Yes, an external PSU should help to get exactly 5V at the 7805 output. Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
maxblanka Posted July 8, 2014 Report Share Posted July 8, 2014 hey i just soldered the level shift buffer circuit, but i am really an idiot when it comes to software. can someone tell me what (and how) I have to do to get a Din sync signal? I read through a couple of things but as i said i am really not into code things... best max Quote Link to comment Share on other sites More sharing options...
TK. Posted July 8, 2014 Report Share Posted July 8, 2014 Open the Tools->MIOS32 File Browser in MIOS Studio, connect to your SD Card, upload the hwcfg/standard_v4l/MBSEQ_HW.V4L file. It has already the right configuration to enable the DIN sync output (J5_ENABLED set to 1) Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
smaudio Posted February 22, 2015 Report Share Posted February 22, 2015 Hi blingy, have you managed to resolve your Din sync lagging issue? I seem to be having the same problem. I have level shifted the J10 clock output from my STM32 and I'm getting 4.99V on the start/stop signal (which works fine), but only around V0.20 on the clock signal. My MC202 does respond to changes in the tempo but it always lags behind a bit. I wonder if there is any way I could compensate for this lagging through the software. Quote Link to comment Share on other sites More sharing options...
smaudio Posted February 22, 2015 Report Share Posted February 22, 2015 Ok, I think I've figured this out - After checking with another Din sync/MIDI converter it looks like it's not the clock being sent from the Midibox seq v4 that's wrong (and thus it's not a matter of voltage), but that the MC202 adds some extra time in the last step of every sequence. This makes it drift. I've worked out that the 202 sequences need to be trimmed a bit at the end to get the two to synch properly. I hope this helps anyone that comes accross the same issue Quote Link to comment Share on other sites More sharing options...
blingy Posted February 27, 2015 Author Report Share Posted February 27, 2015 Never did get din sync as tight as I'd like it to be, ended up just using a 707 as master. Quote Link to comment Share on other sites More sharing options...
cmos Posted June 4, 2015 Report Share Posted June 4, 2015 (edited) Never did get din sync as tight as I'd like it to be, ended up just using a 707 as master. Ah the 707, the true master of many a setup and surely the greatest all round MIDI/sync/trig/converter, but with bonus drum sounds :smile: I too had timing issues with din sync24 out to a 202/303. I think I've solved it, so I thought I'd share the joy. Besides which, I've been lurking for ages, so I hope this first contribution helps other MIDIboxers. Big thanks to Mr Klose (and others) for their tireless work - we are all essentially standing on the shoulders of giants. I'm using a USB powered MBHP_CORE_LPC17 core running MIDIbox SEQ V4. I'm a long way from putting it into a case - just using bulldog clips/stripboard etc for now, though I have stuffed together 1x SD Card bodge, 2x 40x2 LCDs, 1x DIN and DOUT R5 boards, and some loose buttons to get up and running. Initially I hooked up the 303's Sync input to J28.SDA, as documented here: LPC17 connections. To my surprise, my 303 responded, i.e. it did play, although the timing was all off. There was a noticeable but inconsistent lag between some steps every bar or two, making it practically unusable. It was as if the 303 was pausing momentarily on some steps. Sort of an interesting effect, but would clearly cause any dancefloor to react badly. Initially, I thought it probably needed a 3.3V -> 5V level shift with a 541, but that didn't seem make a difference. Time to get the scope out... Here's the din sync clock output from my MC202. 5ms/dev horizontal, 1V/div vertical (though I don't trust my scope's calibration - the poor thing is nearly as old as me). Compare this with the output straight from J28.SDA. You can see it's 3.3V as expected, but the default pulsewidth (1ms?) looks too short. Stuffing this signal through a 541 and tweaking the pulsewidth, I found that 8ms was spot on with the defaults set for clock divider=16 and 24 PPQN. Now we have 5V pulses/square wave (I actually measured the supply at 4.84V with a meter on the 541) and a pic very similar to the first. More importantly, both the 202 & 303 behaved themselves as sync slaves, no longer sounding like narcoleptic amateurs. It even worked at 3.3V, without the level shifter, so it seems Roland isn't too picky about the voltage, but it's all about the pulsewidth setting - check out the CV config menu page for that. @smaudio: the MC202 adds some extra time in the last step of every sequence This seemed to happen only when my 202 was in 'play once' mode. When I saved a short pattern then went into cycle mode (shift -> cycle) the unwanted gap at the end disappeared. I see that using a dedicated DOUT for din syn clocks is now the favoured route instead of J28. I haven't checked this out yet, I'm using a SEQ V4 anyway, and this post is long enough already so I'd best leave it there. I hope the above all makes sense and the scope pics aren't too shabby. Cheers, C Edited June 4, 2015 by cmos Quote Link to comment Share on other sites More sharing options...
cosmosuave Posted June 4, 2015 Report Share Posted June 4, 2015 I have yet to wire up my DINSYNC port but I have to ask what is a 541 and where do you place it? Quote Link to comment Share on other sites More sharing options...
cmos Posted June 4, 2015 Report Share Posted June 4, 2015 541 = 74HCT541, an octal buffer/line driver. There's one in your core board (IC1) already, so you might be able to use it if you have a spare DOUT SR, otherwise check out this doc for connecting the extra bits to J28: http://ucapps.de/mbhp/mbhp_core_lpc17_output_buffers.pdf. That's from the Download/Additional info section of the core_LPC17 docs http://ucapps.de/mbhp_core_lpc17.html Quote Link to comment Share on other sites More sharing options...
cosmosuave Posted June 4, 2015 Report Share Posted June 4, 2015 Ok thanks... Quote Link to comment Share on other sites More sharing options...
cit Posted January 24, 2021 Report Share Posted January 24, 2021 i know this treat /post is a bit old. i have the midiphy v4+ . is it posible to have roland din sync on it? i want to use some tb 303‘s and others on it. ok i have sync boxes etc. but i just want to know if i can use it direct on it? thanks Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.