Keysight DSOX3012T, Руководство пользователя

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CXPI Triggering and Serial Decode
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Keysight InfiniiVision 3000T X-Series Oscilloscopes User's Guide 419
CXPI frames have the following format:
• DLC = Data Length Code
• NM = Network Management
• CT = Counter
To set up a CXPI trigger condition:
1 Press [Trigger] .
2 In the Trigger Menu, press the Trigger Type softkey; then, turn the Entry knob to
select the serial decode (Serial 1 or Serial 2) of the CXPI signal.
3 Press the Trigger on: softkey and use the Entry knob to select the CXPI
trigger type:
• SOF - Start of Frame — triggers at the start bit of any frame.
• EOF - End of Frame — triggers at the end of any frame.
• PTYPE — triggers on any frame that starts with the special PTYPE byte.
PTYPE frames begins with an extra PID byte with a Frame ID of 0000000b
(reserved for only PTYPE frames). The PTYPE PID byte is then followed by a
regular PID byte and the rest of the normal frame. The extra PTYPE byte is
never included in the CRC calculation.
Parity
(1 bit)
Frame ID
(7 bits)
DLC
(4 bits)
NM
(2 bits)
wakeup sleep
CT
(2 bits)
Data
(0-12 bytes)
CRC
(1 byte)
Frame Info
(1 byte)
PID
(1 byte)
Normal frame
Long frame
Parity
(1 bit)
Frame ID
(7 bits)
DLC
(4 bits,
= 0xF)
NM
(2 bits)
wakeup sleep
CT
(2 bits)
Data
(0-255 bytes)
CRC
(2 bytes)
Frame Info
(2 bytes)
PID
(1 byte)
Extension
DLC
(1 byte)