S/UNI®-8x155 ASSP Telecom Standard Product Data Sheet
Released
Pin Name
Type
Pin
No.
Function
The POS-PHY receive read enable (RENB) is used to initiate
reads from the receive FIFO. During a data transfer, RVAL
must be monitored since it will indicate if the data is valid.
The system may deassert RENB at any time if it is unable to
accept more data.
In POS-PHY operation, the information on RDAT[31:0],
RPRTY, RSOP, REOP, RMOD[1:0], RERR, RVAL and RSX
is held on the following clock cycle when RENB is sampled
high.
When RENB is sampled low, the values on RDAT[31:0],
RPRTY, RSOP, REOP, RMOD[1:0], RERR, RVAL and RSX
are valid and are updated on the following clock cycle.
RENB is sampled on the rising edge of RFCLK.
RSOC
Output
AC28
The UTOPIA receive start of cell (RSOC) signal marks the
start of a cell structure on the RDAT[31:0] bus.
In UTOPIA operation, the first word of the cell structure is
present on the RDAT[31:0] bus when RSOC is high.
RSOC is updated on the following clock cycle when RENB is
sampled low. RSOC is updated on the rising edge of
RFCLK.
RSOP
REOP
The POS-PHY receive start of packet (RSOP) indicates the
start of a packet on the RDAT[31:0] bus.
In POS-PHY operation, the first word of the packet is on the
RDAT[31:0] bus when RSOP is high.
RSOP is updated on the following clock cycle when RENB is
sampled low. RSOP is updated on the rising edge of RFCLK
Output
AC29
The POS-PHY receive end of packet (REOP) marks the end
of packet on the RDAT[7:0] bus. It is legal for RSOP to be
high at the same time REOP is high.
REOP set high indicates the last word of the packet is on the
RDAT[31:0] bus. The RMOD[1:0] bus indicates how many
valid bytes of packet data are in the last word. It is legal for
RSOP to be high at the same time as REOP is high in order
to support one, two, three and four byte packets.
The value on REOP is updated on the next clock cycle when
RENB is sampled low. REOP is only used for POS-PHY
operation and is updated on the rising edge of RFCLK.
RERR
Output
AC27
The POS-PHY receive error (RERR) indicates that the
current packet is invalid due to an error such as invalid FCS,
excessive length or received HDLC abort sequence (0x7D-
0x7E).
RERR is high when REOP is high marking the current packet
as erred. RERR is low when REOP is low.
The value on RERR is updated on the next clock rising edge
when RENB is sampled low. RERR is only used for POS-
PHY operation and is updated on the rising edge of RFCLK.
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC- 2010299, Issue 2
54
PMC [ PMC-SIERRA, INC ]
