RoadTest: Agilent MSOX3024A X-series InfiniiVision
Evaluation Type: Independent Products
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?:
What were the biggest problems encountered?:
[Update: 23/10/2011, 03/11/2011]
Hello element-14 members
A few weeks ago with great pleasure an Agilent Infiniivision MSO-X 3024A Mixed Signal Oscilloscope arrived for my testing pleasure. At this point…
Excellent detailed review.
It looks like you put the scope through its paces. I would be much more likely to make a purchase now that you have verified that the instrument meets its promises.
Time for some fun - have found the "Easter Eggs" in the MSO. Press Utility, Options soft key, then soft key number six, three times to display the names of the Agilent team who worked on the design. Or…
Indeed, some manufacturers do that, but it doesn't mean it's correct. The address is still a 7-bit value, with the exception of 10-bit addresses.
Being able to only display an 8-bit address is obviously an error, while having the option to switch between the two is an attempt at making it easier for the engineer to deal with crappy datasheets (really makes you wonder who's in charge of deciding what to put in the datasheet).
Edit: To answer Mark's question, it doesn't matter if you're only left with 3 bits, any value can be represented in any base and the number of bits is absolutely meaningless from that point of view. This means that the address is fully represented in hex, it just happens that it can't go above 127 (dec).
Not to steal John's thunder, but in my experience there isn't a standard when it comes to specifying I2C addresses. Some manufacturers list the address as an 8-bit value as you have listed - in this case the device has 2 addresses, one for read and one for write. Often though the address is given as a single 7-bit value to which a single R/W bit is appended. For instance the datasheet for the Microchip MCP4017 lists the address as "0101111" followed by a R/W'.
I can't speak for the MSOX3024A, but I can tell you the MSOX-2024A allows you to select whether you want to display the address as 7 or 8-bit. The Saleae logic analyser I use for serial protocol decoding also has this option, as do the latest MDO3000/4000 scopes from Tektronix.
I looked up your review specifically to see if you had included discussion of the I2C decode feature on the MSOX3024A. I see that you have. And, I must say, you have put together a great reivew that was easy to read and provided all the detail I was looking for. I have used both Agilent and Tektronix oscilloscopes with bus decode features and I wonder if you could give your opinion on a difference I've noted in how the two manufacturers handle I2C bus addresses.
On Tektronix 'scopes, I2C addresses are entered as full 8-bit hex values, so the R/W' bit is included in the hex value. On Agilent scopes, I2C addresses are entered as 7-bit hex values (with an assumed 0 in the MSB position), and the R/W' bit is tacked on as the letter R or W. You can see this in your review when you show a screen capture of the MSOX3024A decoding communication with Maxim's DS1307 RTC.
Obviously, both approaches work, but the Agilent approach stikes me as a little odd. Here is why: Most data sheets I've seen provide I2C addresses as 8-bit values with the R/W' bit included as the LSB. For example, Maxim refers to the DS1307 address as 1101000 followed by a R/W' bit of either 0 (for write) or 1 (for read). Put that all together and you get 11010000b = D0h for write and 11010001b = D1h for read. These are the values a user would enter into a Tektronix 'scope to detect and decode I2C communication with a DS1307. On the other hand, as shown in your screen capture for the Agilent MSOX3024A, the I2C addresses for the DS1307 are shown as 68W and 68R. These values correspond to the 7-bit I2C address follwed by an R or W to denote an 8th bit. Now, a hex digit should, to me, represent 4-bits of binary. Agilent seems to be using an octal digit followed by a hex digit, follwed by a letter. I find that confusing and awkward. I asked an Agilent rep about why I2C was handled this way, but never got a response.
What has been your experience?
it's very helpful to see this scope put through it paces.Not quite sure I can justify a 3000 series,but you made the decision that much harder not to.
Well this baby is still ticking along very nicely. If anyone has any more questions let me know.
All the options are already programmed into the custom Agilent ASIC, however the customer needs to purchase individual license keys to activate them, or test them with 14-day demo licenses. . The review unit supplied by Agilent and element-14 has all the options activated . Waveform data can be saved onto USB as screen images either in .png, .bmp or as .csv text data.
This is a very comprehensive review. I wish everyone who will roadtest the products can have this detailed verification of the features. It is really nice to read this kind of user's perspective document rather than a product brochure. Points out directly to the needed features. It's good that element14 has chosen you to review this scope. I like the features where saved measurements can be used as reference, infinite display persistence, the lister for the I2C/SPI and the mask limit test.
By the way, I have some questions. Were the hardware modules included in the package or you bought them separately? Also, what are the available report generation tools or report formats that it has (pdf, doc, html...etc)?
Thanks for the review.
Have just rewritten and updated the review to take into account the new v2.0 firmware and other notes.