Xilinx UG181 manual 18Example of Error Flag SnkFFDIP4Err

Models: UG181

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Sink Core

R

When a DIP-4 error occurs on a payload control word (start of burst for the next packet), the Sink core stores a SnkFFPayloadDIP4 flag. If the payload control word was also the end-of-burst control word for the previous packet, then SnkFFDIP4Err would also be asserted for the previous packet. Since the OIF SPI-4.2specification does not distinguish between these two DIP-4 errors, the Sink core will tag each terminated packet with a DIP- 4 error on SnkFFDIP4Err, and each started packet with a DIP-4 error on SnkFFPayloadDIP4.

This is illustrated in Figure 4-19where packet 1 is flagged with a SnkFFDIP4Err and packet 2 is flagged with SnkFFPayloadDIP4. Note that both DIP-4 errors are asserted at the end of the burst or packet.

SPI-4.2 Interface

IDLE

CH 4

DATA

DATA

DATA

CH4

IDLE

SOP

EOP

 

 

 

 

 

DIP-4 Error Calculated

User Interface

Addr4

Addr4

Addr4

 

EOP

---

SOP

--

Data

Data

Data

SnkFFDIP4Err

 

Figure 4-18:Example of Error Flag SnkFFDIP4Err

SPI-4.2 Interface

 

 

 

 

 

CH 0

 

 

 

 

 

 

IDLE

SOP

DATA

DATA

DATA

EOP

DATA

DATA

DATA

DATA

EOP

IDLE

CH 1

CH 1

CH 1

 

 

 

 

 

 

 

 

 

 

 

 

Packet 1

SOP

 

Packet 2

 

 

 

 

 

 

 

SnkFFDIP4Err

 

 

SnkFFPayloadDIP4

 

 

 

DIP-4 Error

User Interface

Addr0

Addr0

Addr0

Addr1

Addr1

Addr1

Addr1

SOP

--

EOP

SOP

--

--

EOP

Data

Data

SnkFFDIP4Err

Data

Data

Data

SnkFFPayloadDIP4

Figure 4-19:Example of Error Flag SnkFFDIP4Err and SnkFFPayloadDIP4

SPI-4.2 Lite v4.3 User Guide

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UG181 June 27, 2008

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Xilinx UG181 manual 18Example of Error Flag SnkFFDIP4Err