ADV7280M CSI-2 ,Between Line end and Line Start detect long packet.

Question

Hi, 
 
 The video from the stereo camera is input to the ADV7280 and processed by the Lattice CrossLink FPGA. 
 FPGA detects Sync Code B8 between line end and line start and judges it as a long packet. Is it correct behavior? 
 I thought that long packet was only asserted when valid data. 
 
 I am attaching the oscilloscope waveform. 
 
 h_sync : FPGA asserts from the start of synchronization pattern &lsquo;B8 up to the last data captured before detecting LP-11 state. 
 Line End : FPGA asserts when Short Packet Data Type Code=0x02 
 Line Start : FPGA asserts when Short Packet Data Type Code=0x03 
 ADV7280-M D0-P : ADV7280ABCPZ-M 9pin D0P signal

Best regard, 
 Takuya

PoornimaSubramani · Accepted Answer

Hi MatsuTaku San, 
 I beleive Yes, Each image frame shall begin with a Frame Start (FS) Packet containing the Frame Start Code. The FS Packet shall be followed by one or more long packets containing image data and zero or more short packets containing synchronization codes. Each image frame shall end with a Frame End (FE) Packet containing the Frame End Code. 
 Please note Decoded grabs of MIPI packet data are available on the ADV7282-M design support files page. This will give you an idea of what the output from the ADV7282-M looks like. 
 Please cross check and compare with the captured MIPI packets are available on engineering zone " 1258.ADV728xMIPIfreerun.zip " at the link below ADV7280 / ADV7280-M Design Support Files 
 MIPI CSI-2 uses short packets for frame events, and long packets for the image data. Between each packet, the link goes into a low-power state in which it remains until more data needs to be sent. 
 Note: 
 As per MIPI specification the MIPI receiver need to terminate the signals correctly. If the Micro processor/ FPGA does not control the termination correctly then the MIPI signals from the ADV7280-M cannot be decoded. 
 For our evaluation of the ADV7280-M we used the MIPI reference termination board available from here: www.iol.unh.edu/.../mipi 
 
 Thanks, 
 Poornima)

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ADV7280M CSI-2 ,Between Line end and Line Start detect long packet.