N5391A i 2 c and spi triggering and decode for infiniium 8000 and 90000 oscilloscopes data sheet quickly decode i 2 c and spi serial packets lower-speed serial bus interfaces are widely used for connecting eeproms, dacs, adcs, and other peripheral ics to microcontrollers and processors. because these interfaces are relatively simple to implement and have few wires taking up board space, they are found in a wide array of embedded designs. two common low-speed serial bus interfaces found pre-packaged on many vendors ics are inter-integrated circuit (i 2 c) and serial peripheral interface (spi). the N5391A triggering and decode for i 2 c and spi software provides the integration of the infiniium oscilloscope, a powerful everyday signal integrity test tool, with protocol analysis capabilities. with this integration, you can isolate serial packets to find sources of errors due hardware related problems and software related problems. quickly pinpoint timing or signal integrity issues such as noise or coupling on your i 2 c or spi bus. easily see the information transfer leading up to or following a particular event or failure. effectively troubleshoot an embedded system capturing and decoding i 2 c or spi buses, correlating them with other signals in the design, such as digital control signals using a mixed signal oscilloscope (mso), and analog signals interfacing with the real world.
2 easy-to-setup dialog box the N5391A triggering and decode application extends infiniium 8000 and 90000 series oscilloscopes ease-of- use advantages to serial data analysis. a dialog box makes it easy to set up the process to perform serial decode. the figures on this page show the dialog box selections for setting up the serial decode for i2c and spi. note that spi comes in a 2-wire version (without a chip select signal) or 3-wire (with a chip select signal and single bidirectional data line) or four-wire version (with a chip select signal and two unidirectional data lines). the software supports the 3 versions. any combination of analog and digital input channels can be used as the data, clock, and chip select sources. the application provides a simple one-button start-of-frame trigger or end-of-frame trigger that automatically sets your infiniium scope to trigger on a generic i 2 c or spi serial packet. this button also automatically scales infiniiums measurement thresholds corresponding to the voltage levels of your i 2 c or spi signal. figure 1: setup dialog box for i 2 c figure 2: setup dialog box for spi
3 on-screen serial decode once the application has been set up and turned on, the numerical decode is automatically displayed below the data signals waveform. in the setup dialog box, you can vary the display format between hexadecimal, decimal, and binary. the numerical decode values are displayed along with minor and major tick marks. the minor tick marks indicate clock transitions for both i 2 c and spi. the major tick marks for i 2 c indicate sections of the serial packet, such as the address, acknowledge, and data. the major tick marks for spi indicate the beginning and end of each data word in the serial packet. you can click on the decode values and tick marks with the infiniium scopes mouse and drag them vertically anywhere on the scope display. figure 3: on-screen serial decode of an i 2 c packet on an infiniium 8000 series. figure 3b. quickly move between physical and i 2 c protocol layer informa- tion using the time-correlated tracing marker. display protocol content using embedded decode in the waveform area. or, see protocol events in a compact listing format using the industrys first scope-based multi-tab protocol viewer.
4 with deep memory the application becomes particularly valuable. you can capture, decode, and search through many packets of i 2 c or spi transmission over a relatively long period of time, maintaining an appropriate sample rate to digitize all the signal details. you can analyze a series of serial packets that lead up to or follow a particular event of interest or failure in the system. you can use additional channels (up to 20 channels in the mso models) to probe other test points in the system to correlate traffic on the serial bus to other causes and effects in the system. on-screen serial decode (continued) figure 4: on-screen serial decode of a spi packet.
5 listing window with automatic click and zoom this application also offers a listing window view with automatic click and zoom capability. when the application has been set up and turned on, a slid- ing tab is available to either show or hide a protocol decode list of all i 2 c or spi packets that have been captured in an acquisition. the listing window shows the index number, time stamp value, and data content of each serial packet in the list. with the listing win- dow, you can easily scroll through all decoded serial packets in an acquisi- tion to find particular events of inter- est or errors in the transmission. the listing window can be shown in full screen to see more decoded packets at one time, or in half screen to see the listing window along with the captured waveforms. the data in the listing win- dow can be saved to a .csv or .txt file for off-line analysis or documentation purposes. figure 5: listing window hidden with sliding tab available to expand . figure 6: full screen listing window of an i 2 c capture figure 7: half screen listing window of an i 2 c capture.
6 listing window with automatic click and zoom (continued) to enable easy correlation between the listing window and the captured wave- form, the listing window highlights those serial packets that are currently being viewed in the waveform display. for instance, if you are viewing five serial packets in the waveform dis- play, the listing window will highlight those five serial packet items in the list. this listing window features a click and zoom capability so that once a particular packet of interest is found in the list, you can click on it to have the scope automatically zoom into that packet for more detailed analysis. figure 8: spi capture with five packets being viewed in the waveform display, highlighting those five packets in the listing window. figure 9: listing window of a spi capture, demonstrating the automatic click and zoom capability. the item in the listing window that was clicked on becomes high- lighted in blue. after clicking on an item, the undo zoom button becomes available in the listing window.
7 oscilloscope compatibility you can upgrade existing infiniium oscilloscopes with earlier software revisions using free upgrade software available for order on cd from http://www.agilent.com/find/infiniium_software and downloadable from http://www.agilent.com/find/infiniium_sw_download. oscilloscope operating system software revision 8000 series windows xp pro a.04.90 or higher 90000 series windows xp pro a.01.00 or higher ordering information to order the i 2 c/spi application software with an oscilloscopes, please order the option indicated in the table. oscilloscope option number description 8000 series 007 factory-installed license for i 2 c and spi triggering and decode application 90000 series 007 factory-installed license for i 2 c and spi triggering and decode application option description N5391A user-installed license for i 2 c and spi triggering and decode application related literature publication title publication type publication number infiniium 8000 series oscilloscopes data sheet 5989-4271en infiniium 90000 series oscilloscopes data sheet 5989-7819en windows ? xp is a registered trademarks of microsoft corporation.
windows ? is a u.s. registered trademark of microsoft corporation. remove all doubt our repair and calibration services will get your equipment back to you, performing like new, when promised. you will get full value out of your agilent equipment throughout its lifetime. your equipment will be serviced by agilent-trained technicians using the latest factory calibration procedures, automated repair diagnostics and genuine parts. you will always have the utmost confidence in your measurements. agilent offers a wide range of additional expert test and measurement services for your equipment, including initial start-up assistance onsite education and training, as well as design, system integration, and project management. for more information on repair and calibration services, go to www.agilent.com/find/removealldoubt www.agilent.com/find/open agilent open simplifies the process of connecting and programming test systems to help engineers design, validate and manufacture electronic products. agilent offers open connectivity for a broad range of system-ready instruments, open industry software, pc-standard i/o and global support, which are combined to more easily integrate test system development. www.agilent.com/find/emailupdates get the latest information on the products and applications you select. www.agilent.com/find/agilentdirect quickly choose and use your test equipment solutions with confidence. agilent email updates www.lxistandard.org lxi is the lan-based successor to gpib, providing faster, more ef? cient connectivity. agilent is a founding member of the lxi consortium. for more information on agilent technolo- gies products, applications or services, please contact your local agilent of? ce. the complete list is available at: www.agilent.com/? nd/contactus americas canada (877) 894-4414 latin america 305 269 7500 united states (800) 829-4444 asia paci? c australia 1 800 629 485 china 800 810 0189 hong kong 800 938 693 india 1 800 112 929 japan 0120 (421) 345 korea 080 769 0800 malaysia 1 800 888 848 singapore 1 800 375 8100 taiwan 0800 047 866 thailand 1 800 226 008 europe & middle east austria 01 36027 71571 belgium 32 (0) 2 404 93 40 denmark 45 70 13 15 15 finland 358 (0) 10 855 2100 france 0825 010 700 germany 07031 464 6333 ireland 1890 924 204 israel 972-3-9288-504/544 italy 39 02 92 60 8484 netherlands 31 (0) 20 547 2111 spain 34 (91) 631 3300 sweden 0200-88 22 55 switzerland 0800 80 53 53 united kingdom 44 (0) 118 9276201 other european countries: www.agilent.com/? nd/contactus revised: october 1, 2008 product speci? cations and descriptions in this document subject to change without notice. ? agilent technologies, inc. 2009 printed in usa, june 1, 2009 5989-1250en www.agilent.com www.agilent.com/? nd/N5391A agilent technologies oscilloscopes multiple form factors from 20 mhz to >90 ghz | industry leading specs | powerful applications
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