Hi Dwayne, Better description impossible. Thank you very much. I will consider this: It is a WIP project, so some more work in it is needed. As you, for me is just a temptation, not a real need. So, definetly, I will wait until it is more developed. 2010/1/21 Dwayne Reid > At 05:15 AM 1/20/2010, Vicent Colomar Prats wrote: > > >They also have a very nice nano-scope. Somebody tried it? Is it really > >usable for quick projects? > > I purchased a DSOnano from SeeedStudio and I've been playing with it > a little bit. I guess that I just couldn't resist the temptation . > > I consider it to be a "work in progress" - perhaps not as developed > as the Bus Pirate but definitely usable in its current form. > > The DSOnano arrived in a thoroughly professional printed paste-board > box. The 'nano itself was nestled in a foam-board cutout and VERY > well protected. The unit arrived with the battery separate in a > plastic baggie and an black-anodized aluminum back panel with a > die-cut piece of 3M "gummy-back" transfer adhesive. The idea is that > you install the battery yourself, then mount the back panel with the > supplied adhesive. > > Incredibly professional packaging. > > Inside the box was a tiny printed manual of several pages. However, > the text was just too small for me to read comfortably. That was > truly not a problem - I downloaded a PDF version of the manual from > the website. In fact, I downloaded a whole bunch of stuff related to > the DSOnano from the website and from ST's website. > > The only complaint that I have about the unit that I received is that > the front 4-way rocker control doesn't work very well. I think that > I can easily fix it by removing the front panel and slightly > enlarging the hole that the rocker protrudes through. But - I > haven't done that yet. I also see that others have had a similar > problem and that it was resolvable. > > > First observations: > > 1) The battery charging circuit is completely bogus. Although they > have a footprint for a proper Linear-Technology Li-Ion charger, its > not stuffed. Instead, they use a single series diode and low-value > resistor that feeds Vusb directly into the battery. I don't expect > long battery life with that arrangement. > > I understand why they did this - they found that the DSOnano would > not operate from the battery charger chip alone. It will work only > if a functioning battery is connected to the unit. This is, in part, > because the LT charger chip goes into a low value of current limit if > the battery voltage is too low (which it is if the battery is missing). > > To their credit, Seeed Studio appears to be listening to comments > made on their forum. I suspect that future versions will use a > proper battery charger and the appropriate power steering circuit to > deal with operation from the USB power input while the battery is > dead or missing. > > > 2) The unit is DC-coupled only. There is no provision for > AC-coupling the input signal. You have to use an external capacitor > if you need AC coupling. > > > 3) The input attenuator compensation networks are not optimum. This > is easily seen when using the built-in square-wave signal source. I > plan to spend an hour sometime to fix this. > > > 4) The menu structure completely sucks. I have some thoughts on the > matter and I plan to bring them up on the forum. > > > Pluses: > > 1) The source code for the early version of the firmware is > completely open. However, the current firmware version apparently > uses some proprietary bits from a 3rd party supplier and that is not > yet available. > > 2) There is already a completely-different firmware version available > from somebody named Frank. That is posted on the website and in the > forum but I don't see source available for it (yet). > > 3) The fixed-amplitude square-wave test signal output is adjustable > over the range of 10 Hz through 1 MHz in a 1-2-5 sequence. Among > other things, it allows one to see that the DSOnano is useable up to > about 200 KHz. > > 4) There is a MAX232 clone chip inside used to generate the supply > rails for the input op-amp. Its inputs and outputs are currently > uncommitted. There are also 2 (or more, I didn't look) UARTs with > their TX & RX lines not connected to anything on the MCU. It looks > to be fairly easy to use wire-wrap wire to connect the UART pins to > the RS232 driver chip. > > > Bottom line: I think that this thing is just too cool for words > . I'm glad that I purchased it. > > dwayne > > > -- > Dwayne Reid > Trinity Electronics Systems Ltd Edmonton, AB, CANADA > (780) 489-3199 voice (780) 487-6397 fax > www.trinity-electronics.com > Custom Electronics Design and Manufacturing > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist