S/UNI®-JET Data Sheet
Released
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If OVR = 1, then discards last frame and go to step 1. Overrun causes a reset of FIFO
pointers. Any packets that may have been in the FIFO are lost.
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If COLS = 1, then sets the EMPTY FIFO software flag.
If PKIN = 1, increments the PACKET COUNT. If the FIFO is desired to be emptied as
soon as a complete packet is received, set the EMPTY FIFO software flag. If the EMPTY
FIFO software flag is not set, FIFO emptying will delayed until the FIFO fill level is
exceeded.
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Starts the processing of FIFO data. Uses the PBS[2:0] packet byte status bits to decide what is
to be done with the FIFO data.
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If PBS[2:0] = 001, discards data byte read in step 3 and sets the LINK ACTIVE software
flag.
If PBS[2:0] = 010, discards the data byte read in step 3 and clears the LINK ACTIVE
software flag.
If PBS[2:0] = 1XX, stores the last byte of the packet, decrements the PACKET COUNT,
and checks the PBS[1:0] bits for CRC or NVB errors before deciding whether or not to
keep the packet.
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If PBS[2:0] = 000, stores the packet data.
If FE = 0 and INTR = 1 or FE = 0 and EMPTY FIFO = 1, goes to step 3 or else clears the
EMPTY FIFO software flag and leaves this interrupt service routine to wait for the next
interrupt.
The link state is typically a local software variable. The link state is inactive if the RDLC is
receiving all-ones or receiving bit-oriented codes which contain a sequence of eight ones. The
link state is active if the RDLC is receiving flags or data.
If the RDLC data transfer is operating in the polled mode, processor operation is exactly as
shown above for the interrupt driven mode, except that the entry to the service routine is from a
timer, rather than an interrupt.
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
283
PMC [ PMC-SIERRA, INC ]
