seppoman Posted July 1, 2007 Report Share Posted July 1, 2007 Would be nice if they could be daisy chained though.Of course they can be chained :) The only question is software support.Seppoman Quote Link to comment Share on other sites More sharing options...
seppoman Posted July 23, 2007 Report Share Posted July 23, 2007 ;D ;D ;DPCBs arrived, first one is soldered. Now I´ll look into the software side :)Seppomen Quote Link to comment Share on other sites More sharing options...
Sasha Posted July 23, 2007 Report Share Posted July 23, 2007 That is great Seppoman, it will go very nice with Willba`s PCB we all waiting for. :) Quote Link to comment Share on other sites More sharing options...
sneakthief Posted July 27, 2007 Report Share Posted July 27, 2007 that looks beautiful! nice work :) Quote Link to comment Share on other sites More sharing options...
drsyncenstein Posted July 29, 2007 Report Share Posted July 29, 2007 Great, all connections nice on a row, not crammed as the original AOUT. Quote Link to comment Share on other sites More sharing options...
Twin-X Posted July 29, 2007 Report Share Posted July 29, 2007 I want one!!! No i really gotta finish my modular and mbseq! Quote Link to comment Share on other sites More sharing options...
brother303 Posted July 30, 2007 Report Share Posted July 30, 2007 Hi Seppo,really nice work! Count me in for one please. This is exactly what I´m looking for to control my ASM-2. Great! ;DGreeeetzBrother303 Quote Link to comment Share on other sites More sharing options...
seppoman Posted July 30, 2007 Report Share Posted July 30, 2007 Hi,thanks for your comments :) please be patient for a while - I´ll meet with TK soon for tests etc. After that we´ll see about how to buy it. I haven´t decided yet about organizing an initial group order or not - in the long run, I hope Smash might be selling them in his shop.A bit early probably, but one service I could provide: For people being afraid of soldering SMT (at least the ones living in the EU so that there´s no hassle with customs etc.), I could solder the DAC for you free of charge - I´ve got a lot of practice and the right equipment, so this takes me about one minute. If anyone needs help in this regard, contact me via PM. :)Seppoman Quote Link to comment Share on other sites More sharing options...
seppoman Posted August 2, 2007 Report Share Posted August 2, 2007 Hi,short update: Today I hacked a small test program into an Atmel, mainly to put out a few voltages, square and saw waves - so no real Midibox test ;). Still have to do some more in depth tests like measuring small voltage differences, looking with the scope for zipper noise (or hopefully the absence of it ;)) etc. but at least I found out that the board seems to be working as intended. I also already connected my SSM2044 test board to it and can hear the filter sweeps from the saw wave, so everything looks promising :)Seppoman Quote Link to comment Share on other sites More sharing options...
Sasha Posted August 2, 2007 Report Share Posted August 2, 2007 Sweeeeps... :P Quote Link to comment Share on other sites More sharing options...
seppoman Posted August 3, 2007 Report Share Posted August 3, 2007 More update: As far as I can tell with my cheap 80ies Goldstar oscilloscope, there´s no digital bleed through, no overshoot/zipper noise, and an overall very clean output :) Only hard transitions (jump Max->Min) on a channel make the other ones slightly blip with a short 1 mV "spike". But according to the datasheet, this is normal. 1mV even after V/Oct amplification, so this won´t be noticeable at all! I´m very happy with the results ;DSeppoman Quote Link to comment Share on other sites More sharing options...
Sasha Posted August 3, 2007 Report Share Posted August 3, 2007 That`s great! Than, we are happy too. :) Quote Link to comment Share on other sites More sharing options...
nebula Posted August 8, 2007 Report Share Posted August 8, 2007 Colour me impressed.Not like "oh that's cute" impressed, more like "I'm not worthy" impressed.I had no idea this was going on behind the scenes, as I was only directed to this thread today when I enquired about MAX525 in the chat, but just let me say to all who have contributed this board:Your dedication, brilliance and selflessness is incredible, and should be an inspiration to us all.As soon as I see a schematic I'm-a-gonna build that bitch. Quote Link to comment Share on other sites More sharing options...
Jaicen Posted August 10, 2007 Report Share Posted August 10, 2007 That is beautiful!! Can I just check how it will work, i'm still not 100% sure of it's capabilities??Is it possible to output 8x Gate and 8xCV's from this one board? Quote Link to comment Share on other sites More sharing options...
stryd_one Posted August 10, 2007 Report Share Posted August 10, 2007 That's right :) Quote Link to comment Share on other sites More sharing options...
TK. Posted August 11, 2007 Author Report Share Posted August 11, 2007 Today Seppoman visited me, and we tested the AOUT_NG module with MIDIbox SID V2.It works great! (what else would you expect? ;-)But the bad news: the serial protocol of TLV5630 doesn't match exactly with the protocol used by 74HC595 (data is latched with different clock edges). In addition, the TLV5630 only accepts 16bit frames, which makes it difficult to chain multiple AOUT_NG modules.After a long discussion we decided to remove the 74HC595 from the AOUT_NG module. The gates have to realized with a common DOUT module, which will be accessed by the driver by sharing some AOUT pins, and using a dedicated RCLK pin.Alternatively a DOUT register of the common DOUT chain can be usedAnd alternatively, some MIDIbox applications like MBSEQ and MBCV provide gates via port J5 of the core moduleSo, this drawback isn't really a "killer"...Sorry for the inconvenience, but I think that you will be able to life with this limitation.Best Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
stryd_one Posted August 11, 2007 Report Share Posted August 11, 2007 Thanks for the update TK! I had a gut feeling you would decide to simply remove the 595 :)Hope you kids are having fun ;) Quote Link to comment Share on other sites More sharing options...
seppoman Posted August 11, 2007 Report Share Posted August 11, 2007 Hi,In this thread http://www.midibox.org/forum/index.php?topic=7777.msg70420#msg70420 there was some discussion about the quality and precision of AOUTs. I´ll answer here:I´m not sure how much more testing I can do with my limited equipment - what I can tell you for now: the output signal is clean and stable, and a connected VCF works like a charm. I don´t have any analog VCOs for testing (and actually for my personal use, I´m also not at all interested in VCOs), so when time comes, someone owning some VCOs and an "old" AOUT should do a comparison between AOUT and AOUT_NG to find out if in real world any of this datasheet stuff does matter.Doing exact measurements of stuff like precision in LSBs is nearly impossible without VERY expensive equipment - both my multimeter and my oscilloscope have a measuring error that probably is higher than 1-2 LSB. What I can and and am going to measure is that probably the deviation/INL is not as bad as 6LSB suggests, because this is like the number that could be reached under most negative coincidences, e.g. bad luck getting a DAC that was just good enough not to be discarded from production, and then this DAC is used in an environment with fast and extreme temperature changes. It´s 6 LSB max and +2/-1 typical. I already tried things like saw/square waves with an amplitude of only a few dozen mVs. They look quite clean and stable.I´d say the precision is at least better than a lot of the commercial CV gear that even often uses 8 bit DACs (!!!). So probably I made too much fuss about these specs anyway. Now I made some people afraid that the quality might not be sufficient for their needs. THIS IS GENERALLY NOT TRUE :) While the old AOUT DACs have slightly better specs, 99.9% of all Midiboxers won´t notice any difference in their application with the NG´s precision. For VCFs, VCAs, drum VCOs etc, the performance is perfect. Even for synth VCOs, as long as nobody has reported the opposite from actual tests, I claim that the precision is good enough for really good results. So, FEAR NO MORE ;) Taking price, availability, features (onboard bipolar option etc) into account, only very special situations will bias the decision enough to make one choose the old AOUT over the NG.Seppoman Quote Link to comment Share on other sites More sharing options...
ilmenator Posted August 11, 2007 Report Share Posted August 11, 2007 After a long discussion we decided to remove the 74HC595 from the AOUT_NG module.The gates have to realized with a common DOUT moduleActually, I see this as a positive point. It increases (software) compatibility between applications, so it should be easier to exchange the original AOUT and the AOUT_NG. Or am I missing something here?Best regards, ilmenator Quote Link to comment Share on other sites More sharing options...
nebula Posted August 12, 2007 Report Share Posted August 12, 2007 Seppo, when do you think we might be able to see a schematic or layout? (Not rushing, just wondering, for the sake of my own MIDIbox roadmap) Quote Link to comment Share on other sites More sharing options...
seppoman Posted August 12, 2007 Report Share Posted August 12, 2007 Actually, I see this as a positive point. It increases (software) compatibility between applications, so it should be easier to exchange the original AOUT and the AOUT_NG. Or am I missing something here?it has pros and cons. The new solution needs one more PIC pin. Software compatibility doesn´t really change as long there are dedicated (non DOUT chain) gate outs. Only using regular DOUT gates - might be a nice solution, only it introduces some slight jitter of about 1 ms.but removing the 595 is definitely a good idea. It would´ve been possible to invert the clock polarity for the 595 to make it compatible, but putting DAC and Gate on the same chain was not the best idea from the start. The problem is: even if you only want to update one CV or gate, both must be sent. In combination with the stupid 16 bit check of the DAC (which is not clearly worded in the datasheet), this produces a lot of unnecessary performance load.So Nebula, I think I´ll do my changes on the PCB and then sleep a few times over it before calling the work done, so I´d say within the next 2 weeks. Availability to order them somewhere might take longer, can´t say anything definite about that yet.Seppoman Quote Link to comment Share on other sites More sharing options...
Otterfan Posted August 31, 2007 Report Share Posted August 31, 2007 I'm just checking in to see the status of the new AOUT. I don't want to pressure anyone, but I'm very excited about a new board. It looks very promising! Quote Link to comment Share on other sites More sharing options...
seppoman Posted September 3, 2007 Report Share Posted September 3, 2007 as some people on the chat also asked about it: I´m in the process of final minor layouting/testing, then I´ll send Smash the files, then it depends on how long his manufacturer takes etc. So don´t expect anything happening until let´s say at least mid October.Seppoman Quote Link to comment Share on other sites More sharing options...
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