PM8621 PMC-Sierra, Inc., PM8621 Datasheet - Page 120

• Manufacturer Part Number: PM8621
• Description: NSE-8G Standard Product Data Sheet Preliminary
• Manufacturer: PMC-Sierra, Inc.

Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2010850, Issue 1
RX_MSG_LVL[3:0]
Table 8 RX FIFO Message Level
HDR_CRC_ERR
CRC_ERR
OUSER[2:0]
OPAGE[1:0]
This indicates the current number of messages in the Receive FIFO.
Values greater than 1000 will not occur.
If this bit is set to ‘1’, the last message slot received was received with an errored CRC-16
field. This bits is updated every message slot. This bit is provided as status only.
If this bit it set to ‘1’, the message at the head of the Receive FIFO has an errored CRC-16
field.
The usual sequence would be to read this register before reading the message buffer to check
if the message buffer that will be read from next has been received with a CRC error. If a
Receive FIFO Synchronization has been started the value of this bit is invalid until the
RX_XFER_SYNC operation has completed. When FAST_RD_EN is a ‘1’ this bit is valid
when RX_FI_BUSY is a ‘0’ following a Receive FIFO Synchronization. When
FAST_RD_EN is a ‘0’ the values of RX_FI_BUSY and CRC_ERR change concurrently and
a further read should be made after RX_FI_BUSY is sampled as a ‘0’ before checking the
value of this bit.
These bits are a reflection of the OUSER[2:0] bits output from the far end and indicate the
value of the received USER bits in the received message header of the last message received
(without a CRC-16 error). These bits are available in the three top level SBS User bits
registers at a bit position equal to the link number.
These bits are a reflection of the OPAGE[1:0] bits output from the far end and indicate the
value of the received PAGE bits in the received message header of the last message received
(without a CRC-16 error). These bits are available in the two top level SBS page bits registers
at a bit position equal to the link number.
RX_MSG_LVL[3:0]
0000
:
1000
Number of messages
0
:
8
NSE-8G™ Standard Product Data Sheet
Preliminary
119