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s4fq7

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Everything posted by s4fq7

  1. Thanks so much I've tested it and it seems fixed. You guys are the best!, awesome support for an awesome product, AD2 is still single handedly the most compact versatile tool I own, I've done so much with it that would have required like 3 other tools :)
  2. Hey Digilent, I was recently trying out some of the beta releases of waveforms including 3.21.22 and 3.21.30 and I ran into an issue that doesn't exist on the stable release 3.21.3 or earlier versions. When you unplug your hardware all the renamed digital pin labels get renamed to DIN0-32 or DIO0-32 instead of retaining there names. This is problematic for me as I am routinely unplugging my AD2 and swapping them between multiple workspaces using multiple wiring harnesses for monitoring different boards. It means that I now need to make sure I save a all workspaces/projects before I unplug an AD2 and that I open the new workspace before I plug it back in otherwise I will lose all my labels on my data analyzer tabs. If possible it would be really great if you could keep the old functionality where it retained the label names on digital pins unless of course you connect a device that doesn't support them at which point all the pins disappear anyways. Clearing the names when the device disconnects makes things a bit more tedius if you are hot swapping your AD2 between different workspaces and wiring harnesses. Also in the future where is the appropriate place to comment on beta related issues? Thanks again for the great software and continued support of your old devices!
  3. I doubt this is the appropriate place to say this so feel free to delete this. But I just wanted to say this is EXACTLY why I love you guys. I know that you will if possible add the most amazing functionality to your hardware over time :) I bought 2 eclipse z7 a year or 2 ago for the purposes of making an arbitrary wave form generator with 256Mb buffer and I was able to make something that kind of worked. And now you are adding deep capture to the scope that makes use of lots of that ram. Thanks guys! I hope perhaps one day you will make the arbitrary waveform generator support giant waveforms too so I don't need to use my half assed AXI DMA design :) Keep up the great work!
  4. So I found the issue. There is a 6.8uH 0603 inductor located between the two capacitors on VBUS right after the fuse. This perfectly matches the inductor suggested in the "EMC (Class B) compliance circuit" shown on page 4 of the 5V DCDC isolation transformer datasheet. https://www.digikey.com/en/products/detail/mornsun-america-llc/B0505S-1WR3/13168098 Unfortunately according to the datasheet this inductor has a maximum rated current of 330mA based on temperature rise. https://www.digikey.com/en/products/detail/murata-electronics/LQM18DN6R8M70L/12476589 This current limit corresponded to the maximum current I was seeing when using the USB isolator PCB. For the time being I shorted this inductor out and it is now driving enough current through the 3 5V DCDC isolation transformers to power the AD2. I'm unsure why the person who wrote the original blog article I was following didn't hit into this issue. Perhaps the AD (original) used slightly less current than the AD2.
  5. Hello I recently wanted to use a USB isolator with my AD2 in waveforms. I purchased the same FullSpeed capable (not High-Speed) USB isolator as discussed in this blog post. https://www.electrobob.com/analog-discovery-usb-isolation/ I made the same modifications he details, an increased power up to 3W, 1A fuse and a 470 uF capacitor. I connected the AD2 via the USB isolator to computer and it was detected fine however when I try and launch waveforms it throws the following error. ``` Device opening failed DptiIO failed ERC:7 out:16 in:0 Device configuration failed (PLL 2). USB: 4.81V 73mA AUX: 0.00V 0mA ``` I'm a little uncertain what the source of the issue is with my USB isolator. I'm hoping someone who has access to the WaveForms source can tell me what the error means. It seems like maybe there is some issue with the available current as it includes 73mA in the error message, but I'm not sure. I did buy 4 of them and solder them all identically and they all appear to throw the same error. I wonder if perhaps something has changed that means it isn't possible to modify these FullSpeed USB isolators for use with the AD2... I have one different USB isolator by a different manufacturer which doesn't have the power modifications made so it isn't capable of supplying enough current to the AD2. When I try to connect with WaveForms to an AD2 via this different USB isolator I get a different error which clearly says there isn't enough power. ``` Device opening failed Device configuration failed (Post AVCC). The device needs at least 2W/400mA from USB cable. To satisfy this: - Try to use different USB cable and computer plug. - Use the USB plug on the back of the PC, not the one on the front panel. - Use short cable, do not use long cable or cable extender. - Use powered USB-hub, avoid un-powered hub. - Use 6V auxiliary power supply. USB: 4.97 73ma AUX: 0.00V 0mA ``` So since when I am using the modified usb isolator cable of putting out 3W I don't get this power error it seems like it is receiving enough additional power. Also it looks like the original error I was getting isn't related to a power issue perhaps as the power details appear to be included with every error. Can anyone tell me what is failing when it shows me the following error? ``` DptiIO failed ERC:7 out:16 in:0 Device configuration failed (PLL 2). ``` Update 2: I just tried connecting a 5V power supply to the unit and it seems that with the 5V power supply connected it allows me to connect. I wonder if perhaps there is some issue with the 5V DC DC isolation transformers taking too long to respond, or perhaps the 470uF capacitor is insufficient.... It doesn't say there is insufficient power, but the error might indicate the power is not stable perhaps ... Update 3: I attached a usb power supply to 3 of the same 5V DC-DC isolators and fed that into the AUX power input on an analog discovery. The power supplied via the exact same buck converts via the AUX input caused the device to function fine. It seems there is something about supplying the this same power via the USB cable to the AD2 that is resulting in the issue.... I'm going to try running two wires directly from the USB power lines into the AUX power input to see if that works as well... Thanks!
  6. Hey @attila, It worked perfect, I have no idea what I was doing wrong with my exported CSV from libreoffice calc. Export and Import worked perfect though :) Thanks!
  7. Hey @attila, totally unrelated to my original question but I had one suggestion for a feature improvement. (or maybe it's already a feature and just I don't know how to use it). When you are creating a pattern generator pattern of type custom. You can import data. I was trying to import data that included tri-state values but no matter what I typed in the csv file <empty>, "Z", "z", "?" It always seemed to import them as 0. I could easily change all the 0's into "z" by typing "z" and pressing tab, and that worked in the end, but it would be good to document what value to type into the csv so when you import it as a pattern it will show up as the tristate z value. I appologize if I'm missing something obvious. I wanted to congratulate you guys on an awesome piece of kit. I make use of both the analog discovery 2 and digital discovery all the time and they have helped me learn a lot, and as of yet I haven't had any issues with them :)
  8. Hey Atilla, thanks so much for your reply! After much trial and error I think I've decided that the TXB0101 should work as the bus appears to be push-pull and not pull down only. I realized my attempt to reverse the driver circuit had missed that the gate of the p-mosfet was actually attached to a second pin on the micro-controller. So it looks like they are using one pin to read and another pin to write with a push pull configuration using diodes and mosfets. https://crcit.net/c/bbe5bc1e41bf4d05bf6772c45e16e1a0 As such I'm going to just give the TXB0101 a shot and this question can be marked as closed.
  9. Hello, I'm attempting to use the digital discovery to debug a circuit by listening and injecting data on a signal. The signal appears to be pulled down to 0V typically but then pulled up to 5V to transfer data. I've configured everything in Waveforms such that the pattern generator is outputting as open source and this appears to be generating the correct effect on the bus as monitored with an oscilliscope, however it is only achieving 3.3V (as that is all the digital discovery is designed for). Unfortunately this is insufficient for the receiving ends to detect and respond too. I've attempted to use a mosfet based bi-directional level shifter exactly as described here https://scienceprog.com/simulating-mosfet-based-bidirectional-3-3v-to-5v-logic-level-shifter/ However it doesn't play well with the fact the bus is normally pulled down. But this level shifter circuit causes both the 3.3v and 5v side to now be pulled up all the time (and doesn't play well with the bus I'm trying to work with). If I change the patter generator from open source and floating to push pull and normally 0 I can now get it to send a proper signal on the bus, but the response is pulled down way to low by the level shifter circuit to the point I can't capture it with the logic analyzer. I'm relatively confident a circuit can be easily built to allow for a levelshifter that will function with the "open source" bus I am trying to monitor and communicate with but it is going to be different than the one I linked above. It will probably need a p-mosfet and some diodes. Unfortunately I'm not familiar enough with the correct terminology to know what such a level shifter circuit would be called. If anyone can direct me to some resources that explain how to make a level shifter that can perform bi-directional shifting of a bus which is typically pulled down and then pulled up to communicate I would very much appreciate it. If I invert the pattern to be the opposite signal and then feed it to a p-mosfet I figure I can get a 5V output signal, but this might mean I'de need to use one pin to generate the signal and another pin to capture with the logic analyzer. I'de really prefer if there was a level shifting circuit I could make so I could use one pin for logic analyzing and pattern generation. Here is a link to my attempt to reverse engineer the circuit between the external connection on the bus and the microcontroller. https://crcit.net/c/003faefa673e4e8789dddcd1646bedd3 I'm not sure if this is a level shifter or just a diode protection circuit to protect from static and bad polarity but I'm starting to think it may be both. I identified both p-channel mosfets (https://pdf1.alldatasheet.net/datasheet-pdf/view-marking/1241407/YANGJIE/BSS84.html) and n-channel mosfets (https://www.jscj-elec.com/gallery//file/2N7002KLW SOT-323 V1.pdf) as well as diodes. Hopefully this looks familiar to someone. Perhaps the resistance values can help inform someone on what might be appropriate resistance values to use in a level shifter circuit to ensure the pull down resistors on the bus are still effective. (I don't know the capacitance values) Thanks for any help you can provide. EDIT: I found the following stack exchange article https://electronics.stackexchange.com/questions/162398/bi-directional-level-shifter-circuit-with-pull-down-resistors Unfortunately no answer was provided that worked besides buying a custom IC by TI. On page 12 of that IC there is a block diagram which somewhat resembles the circuit I reversed from the PCB https://www.ti.com/lit/ds/symlink/txb0101.pdf EDIT 2: After familiarizing myself with the datahset for the TXB0101 I'm not sure it will work in my situation. It says it is ideally designed to work in cases where push pull cmos logic is used. It can function in cases where pull-up or pull-down resistors are used but they should be greater than 50kOhm to function decenty. Based on my reversed circuit from the PCB, it seems that perhaps the pull-down resistors (if indeed they are pull-down resistors) on the bus are in the order of 5kOhm-10kOhm which would be too low for the TXB0101 to function properly. For I2C style pull-up type buses TI also offers the TXS0101 but if I do have a pull-down type bus(?) it wouldn't work for me. I will buy one to try anyways but it will take afew weeks to arrive. If anyone has any tips or comments on possible level-shift circuit solutions I would still very much be interested. I'm also perfectly happy to purchase a pre-built IC if one exists that would work with the pull-down resistor values on the bus (if that's what they actually are). I don't know how to properly measure the pull-down resistance of the bus, but if anyone can tell me how I will gladly do it. I've also posted a similar question on stack-exchange for anyone who might read this in the future and is interested. https://electronics.stackexchange.com/questions/625974/designing-a-bi-directional-level-shifter-for-3-3v-5v-that-works-with-pulldow
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