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How to decode a protocol like SPI by using MSO9104A?

Question asked by jenaflex on Jun 20, 2012
Latest reply on Jun 26, 2012 by algoss
Hi, I am using MSO9104A. I want to decode a non-standard SPI protocol (like SPI, but not). There are MISO, MOSI and CLK (no Chip Select).  

I tried 14-days SPI option trail. My settings are as follow: 
4 wire SPI; 
MISO - Channel 2
MOSI - Channel 3
CLK   - Channel 1
Chip Select  - Channel 4 (I tried ground it and set "active low"; also I tried give it 5V and set "active high")
Auto Setup;
Trigger: Serial: Channel 3 (I want to select CLK channel as Trigger, but the only options are channel MISO and MOSI.)
Trigger (another try): Edge: Channel 1 - CLK; falling;

others are default.

I always got the message - "can't decode. not enough edge."

I just need to figure out how to decode MOSI and MOSI based on the CLK.

For example, I can decode some by hand. When CLK is active, count the level of MISO such as "high low high low low low low low" (101010000)bin=(A0)hex. Then, convert 8 bit binary value to hex.

How to use agilent oscilloscope to do this?

Thanks a lot.  

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