SainSmart DDS120 & DDS140 USB Oscilloscope

[doctormord]

Maybe the recompiled version on a 64bit machine will do. Let me know about your progress.

[doctormord]

Any progress?

[zp1956]

Unfortunately, not yet

I have tried to compile your code using fresh installation of Visual Studio 2015 Community Edition, but there is still code which should be modified.
In addition, I have tried with couple disassembler tools (Reflect, ILSpy, ..), and result is similar.
Now, my priority is to refresh one very old wah-fuzz stomp box, so I am going to use DDS120 software as it is. Modification of software is postponed.

[doctormord]

Someone may try:

http://www14.zippyshare.com/v/g5cFy1de/file.html

Straight x86 compilation.

pw: dds120

[bianchifan]

IT works on win7/64, thank you! 
Nevertheless a little note..the icon text from the scope window sidebar which appears on mouseOverIcon is still chinese..

[antrrax]

It would be possible to include the pulse trigger? For example in a square wave to trigger a greater or lesser "X" milliseconds of a negative or positive pulse.

[doctormord]

IT works on win7/64, thank you! 
Nevertheless a little note..the icon text from the scope window sidebar which appears on mouseOverIcon is still chinese..

Okay.

It would be possible to include the pulse trigger? For example in a square wave to trigger a greater or lesser "X" milliseconds of a negative or positive pulse.

The DDS120 got no hardware-trigger and the actual software-solution isn't capable of doing that. As the DDS120 just streams the ADC-content, this (to my knowledge) can't work. From the code i'd seen, implementing "pre-roll/delay" for trigger would result in a completely rewrite of the code. The code itself is coded with "DMA" and unsafe statements. So if someone knows how to do, i do not. 

[antrrax]

No problem man!!!
I just thought that with this new accessory would be possible to implement a new trigger in the program.

http://www.sainsmart.com/sainsmart-hardware-trigger-module-for-dds-140.html

-------

You could tell what function this accessory the link above?

Thanks

[doctormord]

This hw-trigger is for the DDS140, which is != DDS120. 

[bianchifan]

IT works on win7/64, thank you! 

After checking the software out I got such a divice at least, I choosed DDS140 fo rless than 80 bucks from Amazon.
Your SW doesn't recon DDS140, it seems, only "104/140"-specified version will run.
So I have to use shipped out one 1.4 from 2014.

Update:
.......
To compile und linux/ubuntu, you need to have libqt4-dev (or libqt5-dev) and fftw3-dev installed. To access the device as a user, add this to /etc/udev/rules.d/50-sainsmart.rules:

Code: [Select]

#add SainSmart DDS120 and DDS140 to group plugdev
#DDS120
SUBSYSTEM=="usb", ATTR{idVendor}=="8102", ATTR{idProduct}=="8102", GROUP="plugdev"
#DDS140
SUBSYSTEM=="usb", ATTR{idVendor}=="8312", ATTR{idProduct}=="8312", GROUP="plugdev"

and make sure that your user is member of the plugdev group.

All done, it compiles fine.
My DDS140 is recognized as Buudai104 , unfortunately the screen is empty, no waveform and no waveout on the device.
Do I need FW-extraction and loading scripts like on the Hanteks?

[doctormord]

Right, my software is actually only for the DDS120/Buudai102 as i stripped some code to cleanup and understand whats going on.

May you upload the 1.4 somewhere?

Regards,

Christian

[bianchifan]

At the moment I'm a little disappointed..
Ok, 16MHZ can be displayed, but the device/AD is quite noisy, no stable curves, triggring 
Test signal, what? 
Measure window is only a bad joke.
The scaling on Y even, for ex. 5V USB Voltage will show a line at 6.3 V, with 1/10 divider at 0.59 V.

DDS140 V1.4

[doctormord]

Are you complaining about the Channel 2 reading? I would suggest to switch this channel on first - it's actually off at both screenshots.

[bianchifan]

Are you complaining about the Channel 2 reading?

?
Of course CH2 is switched off when nothing to do.
But I can tell you, it's quite analog to CH1.
My pics are showing the test signal, should be square...
Even a slowfrequent triangle from an old XT2206 has noiserounded edges.

I attach some more pics:
- test signal how it should look like due to help screen
- USB voltage from breadboard supply, should be 5.03 V
- same through probe divider
- noise from shorted CH1 at 1V/div - 200MSamples
- same at 50mV/div
- clock signal at 16MHz crystal of an ATMEGA16 circuit

EDIT:
Forgotten..
CH1 triggers when time base is less/equal 0.1 ms
CH2 triggers never, no way 
When stopped (triger ext.) it displays a much better waveform, only slightly rounded.

[doctormord]

May you upload the 1.4 somewhere?

Have you tried to run a "calibration" with both channels on and shorted? That normally cancels out the offset for each voltage setting. If this doesn't help, i'd blame the multiplexer they use. There were some issues with this in the DDS120 as well.

[bianchifan]

May you upload the 1.4 somewhere?

DDS140 V1.4

Have you tried to run a "calibration" with both channels on and shorted?

Surely, of course I did so.

At least there are two probs, HW and SW!
For ex. within the loupe func you should be able to scroll left and right..unfortunately the arrows are greyed out always.
As long as I'm able to work bugs and glitches are a only a minor problem.
Displaying wrong values however sucks...

Two examples:
1st, absolute value, USB Voltage / AVR supply, roundabout 5V (4.8V - 5.13V may occur)
5Volts are "transformed" to 6.4V - 6-5V., three possible scenarios:
- resulting voltage < 6.4V  ->  curve will be displayed
- 6.4V < result < 6.5V  ->  Curve is displayed and a wrning message is blinking, sometimes paired with beeps- .
- result  > 6.5V  ->  blank screen, loud beeps and permanently flashing warning "Out of range!"

2nd, relative value, by 10 divided signal in 100mV/div area
Changing the screen divider to 50mV/div should double the value.
Depending on signal form and noise the value raises about 10-30%...
Changing to 200mV/div should halve the value.
Depending on signal and noise the value decreases mostly between 20% and 40%...

On youtube I found a video where the 1kHz test signal looks like it should, so maybe my device is faulty Monday crap.


Should I return it?
Or fuck the warrenty, open it and try for tuning up?

Yesterday I soldered q&d an AVR-DDS, it's quality isn't the very best but not as shitty as on my poor screen 

With these curves I wouldn't complain

[doctormord]

I would return it, this device is pretty much out of spec.

Thanks for the upload.

[zp1956]

Finally! I have my own source code working!

@doctormord
Using your executable file version 1.3.1 and decompiler/compiler pair ILSpy/SharpDevelop, I got my own customized DDS120.EXE file.
Now, as a first step I am going to change those ugly icons (since I am not native C# programmer, I have to work carefully  ).

[doctormord]

Nice, haven't thought it will work with SharpDevelope.

[bianchifan]

I would return it, this device is pretty much out of spec.

Maybe, but at least I couldn't resist and opened it and took some pics.

Front PCB


Backside


Bad soldering, looks manually

[doctormord]

Hmm, no AD adc anymore, but a chinese "pin compatible" MXT2088.

[bianchifan]

Hmm, no AD adc anymore, but a chinese "pin compatible" MXT2088.

The only datas I could find are telling 8bit ADcv 100MSPS, 90mW 1Vpp..I cannot read chinese and I'm too lazy translating those fuc...datasheets via google.
I do not think it causes the told probs.

[doctormord]

Well, they state +-500mV FS while the AD is +-512mV. Maybe a translation error as most of their data is same as AD, even in the order.

For the voltage error have a look at the gain stage resistors.

If the error is same in percentage for different ranges, I'd check the ref voltage/s at the ADC. Maybe the MXT2088 isn't that linear at the top end.

[bianchifan]

For the voltage error have a look at the gain stage resistors.

If the error is same in percentage for different ranges, I'd check the ref voltage/s at the ADC. Maybe the MXT2088 isn't that linear at the top end.

I did a few quick checks only, all seemed ok.
ON Sainsmart's HP I found an older version of DDS140.exe (v 1.2) inm Analyzer/Generator sections offered as The Newest Version
1. It displays 16 MHz same known shit but it displays.
2. Slew rate / steep curves same bullshit, even 100 Hz rectangles show rounded edges.
3. Loupe same crap, use with care, no side shifts
4. No more "Out of Range" with 5V, all signals were shown and sometimes they were triggered too.
With AC selected, Voltage is fine, 4.93 V differed between 4.89 and 4.97 V, triggerpoint is the middle vertical line.
Rising/falling seems fine, trigger level is a little mystery, only no trigger was working.
Zero adjustment has an offset of .5V, thumb ruled.

With DC selected I didn't notice any "out Of Range" too.
Depending on the selected V/div it was too high, i.e. 5.8V in 2V/div and 5.6V in 1V/div thumb ruled instead of 4.93V.
Rising/falling seems fine, trigger level is absolutely mystery, maybe for selecting the voltage area, a signal have to cover completely.
With the "T"-LIne you can mark an area froom Zero to "T", all curves staying between these lines are displayed, "normal" and "single" will do.

[doctormord]

So you'll check the resistor values at the range switch "CD40xx", maybe they aren't in the 1% or better range.

You may also check if the voltage levels are changing vs temperature.

As far as I remember the code, there's no 2 point calibration at all, just offset calibration for the zero line.