Agilent 3000 X-series options - Page 1
Forum section: electronics / testgear

author: alexanderhiam
author_rank: Contributor
timestamp: April 07, 2013, 07:09:38 pm
content: Hi all,I've been considering breaking the bank for one of the Agilent 3000 X-series scopes, and I would like to have the mixed signal capabilities (I'm thinking the MSOX3014A). What's got me confused, though, is how the mixed signal models actually differ from the standard DSO models. If all the protocol decoding costs extra (about $1500 USD more to get I2C, SPI and UART/RS-232 decoding!!), and there's no hardware differences between the DSO and MSO models (am I wrong here?), then is the $500 difference between them just buying the software to do basic triggering and sampling? Doesn't that make for just about the most overpriced and feature limited logic analyzer money can buy?!

author: CarlG
author_rank: Regular Contributor
timestamp: April 07, 2013, 07:29:57 pm
content: I'm not sure I understand your question 100%...no, there's no HW differencies between the DSO and MSO scopes. What you get with the MSO model is enabled 16 digital channels plus you get the digital probe kit (so there's some HW difference)But the serial decode options are available on the DSO as well as on the MSO models. One benefit with the MSO is that you can decode two buses simultaneously, e.g. one full SPI (SS, SCK, MOSI, MISO) plus one I2C. (though not two SPI's simultaneously)

author: alexanderhiam
author_rank: Contributor
timestamp: April 07, 2013, 07:44:20 pm
content: I guess what I'm asking is if the decoding upgrades apply to both the analog and digital channels, or if the MSO versions come with any decoding on the digital inputs without upgrading.

author: Christe4nM
author_rank: Unknown
timestamp: April 07, 2013, 08:10:50 pm
content: Same here, I'm saving up for the entry model of the 3000X series, but am still not sure whether to spend the money on the MSOX vs the DSOX.What I've discovered so far is this (please correct me if I'm wrong):The MSOX capabilities are hardware based. So logic analyzing and triggering is done in hardware. The MSOX licence makes that available to the user. With the DSOX you might indeed have the same hardware, yet the logic inputs are not available to use for you. The main difference is that with the DSOX you will be limited to only 2 or 4 input channels, depending on the model. With the MSOX there's your standard 2 or 4 channelsplus8 (2000X) or 16 (3000X) logic channels. Now you can combine the 'analog' channels with the logic channels hence the name "mixed signal" oscilloscope. Possibly the analog channels add to the logic channels as well turning your MSOX3xxx into a 20-channel logic analyzer.So you pay for the ability to have 16 logic channels in your 3000X series scope available to you, hardware triggered and decoded. As far as I understand their bandwidth is the same as your scope's bandwidth. Mind that the specific bus decoding protocols arestill locked, and can only be accessed by purchasing their respective licences. And yes, those licences apply to the complete instrument both analog and digital channels.OK, so why would you want to buy the MSOX or rather a DSOX and separate USB logic analyzer? I think that comes down to the following:- The MSOX option is quite expensive compared to a separate logic analyzer- The MSOX triggers and decodes in hardware, where most logic analyzer's I've seen use their firmware to do so. (Again, correct me if I'm wrong)- A separate USB logic analyzer uses you computer's display which is bigger and has greater resolution than the scope- The separate USB logic analyzer's softwaremighthave more elaborate functionality. And at the least its decoding functionality is directly available to you without extra licences.- If you want to view your analog signal at the same time base as your logic signals, the MSOX wins hands down. I suppose this is quite useful for DSP and DDS.Concluding, even with this information I'm not sure yet why to choose the MSOX over a DSOX with separate logic analyzer. In my case I'm doing both analog design as well as embedded and FPGA stuff. So saving up for an 3000X I'm seriously considering the MSOX functionality. Do I really need it? I'm not sure, so maybe I'll just start with the DSOX with the decoding options I need and decide later on if I need the extra logic inputs.I do not want to hijack your tread, but maybe people can chime in about MSOX vs DSOX uses / usefullness and MSOX vs USB logic analyzer. let me know if this is (too) off topic for your liking and I'll start my own thread.(edit: typo)

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: April 07, 2013, 08:19:56 pm
content: It basically just boils down to having more channels.Even for digital stuff you normally use the analogue channels. When you run out of those you use the digital ones.If you only have 2 analogue channels, this is often not enough - 4 analogue is a lot better but sometimes you still need to see more things at a time. Another useful thing that digital channels allow is display of a group of signals as a bus, displaying the value on the bus as binary, hex or ASCII values.Having them together makes it much more useful, as you can immediately see what is happenning in both the analogue and digital worlds. Yes you could use a seperate analyzer but it's a lot less convenient.It is a completely seperate issue from any decode & trigger options. Decodes can use analogue or digital inputs.

author: EEVblog
author_rank: Unknown
timestamp: April 07, 2013, 09:34:39 pm
content: Quote from: alexanderhiam on April 07, 2013, 07:09:38 pmThe MSO option gets you the very nice 16 channel probe system, but no, apart from that there are no hardware differences.If you buy a DSO now and then an MSO option later, they just ship you the probes and a software key.All the serial decode options are built into the ASIC on all models (even the 2000X)

author: EEVblog
author_rank: Unknown
timestamp: April 07, 2013, 09:38:05 pm
content: Quote from: Christe4nM on April 07, 2013, 08:10:50 pmThat's the main advantage of a mixed signal scope.Which also includes convenience not having to use a PC on your lab bench etcQuoteThat's why Agilent made it an option, you can always buy it later.

author: alexanderhiam
author_rank: Contributor
timestamp: April 07, 2013, 09:56:50 pm
content: Thanks guys, it's making a lot more sense now. I was thinking of it more as just slapping in a separate logic analyzer to the DSOX version. I've been using the much cheaper Saleae Logic16 USB analyzer, which has a whole host of software decoding features, so it seemed a bit crazy to me that for the price of the MSO upgrade you don't get any serial decoding at all.Obviously there's many more benefits to adding 16 additional digital channels to the scope that I hadn't considered, so yeah, I guess I could see paying $500 extra dollars for that. I just checked the prices again, though, and I had it wrong. It's not $500 more for the MSO option, it's $1200!So, yeah, it's definitely a pretty handy option, but I think I'll start with the DSOX.

author: CarlG
author_rank: Regular Contributor
timestamp: April 08, 2013, 06:05:24 am
content: As I see it, a protocol analyzer may be more useful for code debugging, while a (MSO-) scope is more useful for HW debugging and verification.