Sure RemiD
Start with this link
http://www.seeedstudio.com/wiki/DSO_Quad
And you will also find these helpful
<LINK_TEXT text=“http://www.seeedstudio.com/wiki/DSO_Qua … mmunity%29”>http://www.seeedstudio.com/wiki/DSO_Quad_Manual_(by_the_community)</LINK_TEXT>
// various source files if you choose to tinker with the code
ftp://shodtech.net/DSO_Quad/
Hope this helps
Jerson
You can also look here: <LINK_TEXT text=“http://hifiduino.wordpress.com/2011/04/ … art-guide/”>http://hifiduino.wordpress.com/2011/04/30/dso-quad-quick-start-guide/</LINK_TEXT>
Thanks for the links, but i see the explanations are for the DSO Quad and i have a DS203.
Can i use the same SYS and APP on the DS203 ?
Sorry for all these questions but i don’t want to rush and break the device ! I hope you understand.
Thanks,
if (DSO Quad == DS203) Links_ok.
else Whats_a_quad?
Seriously, the two are the same thing.
Thanks for these precisions.
The device seems to work correctly with the updates. 
some bug report or something
have difference with detect high frequency more than 5 Mhz - FIRST pictures
inaccuracy 8%-10%
and half difference with detect dso generete signal by yourself low frequencies - LAST picture
Thank you for your work! spectro analizer very help
Hi, I have just loaded this app on my Quad to resolve some shortcomings in the 2.53 app (no x10 probe support and I could never get the FFT to work properly) so very pleased with this version, thanks for all your efforts and hard work.
I have one question, when using the FFT the readouts in red flicker, especially bad on the predominant frequency reading and the Div reading at the upper left corner. Is this correct or have I missed something?
I have installed Sys 1.50 SmTech 1.6 GCC 1.21 App (2.51 + SmTech 1.8 + PMSO69 fixes) I am not sure which FPGA is installed (how can I tell?) and can this affect the flicker problem?
Please excuse if any of these questions are silly but this is the way to learn. Thanks for any help or advice.
Hi again, I have just noticed another weird thing, if you are using the quad while connected to my laptop by the usb lead all the voltage readings are way way out (2.6v p-p reads +0.578k !!) and can only be corrected by disconnecting the usb lead and rebooting. Any ideas?
Too many bugs and too little time.
I haven’t been able to touch the code since the last build, sorry.
Dive into the code guys. It won’t bite you 
Please don’t think I’m complaining, I really appreciate all the effort everyone has put in to make this a useable tool. I have now worked out that the measurements only go silly if you have FFT on AND connected to the PC, no real problem to work round. I was also only wondering if the flickering, I described a couple of posts ago, was to be expected or whether I had more stuff to instal or upgrade.
Yes, it’s just lazy programming.
When the waveform box is “printed” to the screen, it’s done drawing complete vertical lines (with the waveform dots in the middle) from left to right, so that erases the previous screen content in that area. Only then is the text printed on top of that.
To eliminate the flickering of text written in the waveform box, the text witting would have to be incorporated in the line drawing sweep itself, or something like that…
Yeah… here is some code for that if someone is really bothered by the flickering
https://svn.kapsi.fi/jpa/dsoquad/logic/gui/
vblack comes to the rescue
No flickering any more.
[code]v1.22
- FFT flickering fix, with improved drawing code (vblack)[/code]
Latest download: https://github.com/pmos69/dso203_gcc/zipball/master
Thanks, this looks so nice now. I appreciate all the effort everyone has put in to this program, it makes the Quad a useful tool instead of a toy. Thanks again, Mike
Hi all,
Is there thread with current list of major bugs, which needs to be fixed? I can try to fix them.
Well, apart from the hardware part, which has major flaws but is out of our reach, and the triggering issues that are part of the fpga, the calibration, or better yet, the measurement corrections part also has major issues, especially in relation to the vertical alignment.
Not having easy access to extra equipment to help test this part has kept me from looking at it.
Can I mention a couple of things?
Having installed the “flicker free” App I now notice that on the digital inputs vertical transitions are in a different colour from the trace colour. ie with either a square wave input or a saved waveform on Ch4 the horizontal line is green but any rise or fall appears in cyan, Ch3, normally magenta, shows white on vertical transitions, any ideas?
The bug that affects me most is the horizontal misalignment of the digital and analogue channels. The analogue appears delayed from the digital when fed with the same input. The displacement is 1 graticule dot and doesn’t change with timebase settings which suggests this is not a signal timing error through the input circuitry but possibly a sampling problem, a solution would be great.
Regards Mike
Just one dot/sample?
Which one is delayed (further to the right)?
I fix the color issue.
Regarding issue with Analog/Digital delay. On my DSO I have digital delayed a lot in compare with analog (See attached screenshot).
That’s a huge delay 
Does the timescale make any difference?
Some people mention 1 sample delay, others 5 samples, and now this…
This even seems to be the opposite of what others are seeing.
EDIT: Just checked my quad and have results like previously reported: About 5 samples delay on the analog channels compared to the digital channels.
Timescale makes no difference - Delay is constant.