PM8379
CTS 20x4G
Advance
20-Port 4.25 Gbit/s FC-AL Cut-Through Switch
The CTS 20x4G is designed to interface
directly to Fibre Channel disk drives in a
storage array. It can interface directly to
optics or to cables at the ingress/egress
point of an enclosure and is able to
determine if an incoming frame is
destined for a drive within that enclosure.
After determining which port is
associated with the frames recipient, a
cut through operation to that port is
performed thereby significantly reducing
system latency and improving perfor-
mance.
The CTS 20x4G provides unique disk
isolation features that significantly
increase total system availability,
reliability, and serviceability.
• Built-in self test capability with FC
Frame Generator/Comparator.
• Supports a 106.25 MHz, 40-bit (20
receive + 20 transmit) DDR parallel
interface that acts as a 21st port. This
flexible interface enables external
functions such as enclosure
management or other user-proprietary
functions to be implemented using a
low cost FPGA.
CUT-THROUGH SWITCHING
• Integrated cut-through switching and
arbitration management enables up to
200% improvement in EDR and IOPS.
• Parallel arbitration supported with
arbitration priority and access fairness
preserved.
• Automatic or CPU controlled
initialization of AL_PA table.
• Supports dynamic half duplex, half/full
duplex operation, LPSM transfer state,
multicast/broadcast (OPNy).
FEATURES
GENERAL
• 20 independent rate selectable 1.0625,
2.125 or 4.25 Gbit/s physical
interfaces.
• Register and software compatible to
the PM8368 PBC 18x2G, PM8369
PBC 18x4G, PM8372 PBC 4x2G and
PM8377 PBC 4x4G.
• Compliant to FC jitter specifications on
a per-port basis.
• Supports single-ended or differential
106.25 MHz reference clock.
• Per port monitoring and diagnostics:
•
LPSM Monitoring on each port.
•
Disk isolation and per port serial
loopback.
•
Configurable Digital Loss of Link:
analog LOS Detect, 8B/10B
disparity errors/error rate, CRC
errors/error rate, word
synchronization error/error rate, and
compliant frequency of comma
patterns detected (configurable
thresholds for each with
corresponding pin interrupts).
BLOCK DIAGRAM
CTS Logic
Arb
Mgmt
Cut Thru
Mgmt
AL_PA
Table
Frame Generator
Frame Comparator
RDIN[0]
RDIP[0]
RX SERDES
RDIN[1]
RDIP[1]
RX FIFO
TX FIFO
TDON[0]
TDOP[0]
RX FIFO
TX FIFO
TX SERDES
TDON[1]
TDOP[1]
RDIN[19]
RDIP[19]
RXCLK
RXD[19:0]
RX FIFO
TX FIFO
TDON[19]
TDOP[19]
RX FIFO
TXD[19:0]
TXCLK
JTAG
CDRU
CPU
CONTROL
MDIO_SDA
REFCLK_P
EXTCAP
REFCLK_N
MDC_SCL
CLK_SEL
TWI_SEL
DLOLB
TDI
TRSTB
FULL_RATE
DEVBYPSB
RESETB
INTRB
DLOLBYP_MSK
TRUST_MODE
RECEQUALIZ[1:0]
MON_BYP_PORT
REFCLK_S
PREEMPH[1:0]
PMC-2031144
Issue 2
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC.,
AND FOR ITS CUSTOMERS’ INTERNAL USE
DVPRTAD[5:0]
© Copyright PMC-Sierra, Inc. 2004.
All rights reserved.
BYPASS[20:0]
OENB
TCK
TDO
TMS
PMC [ PMC-SIERRA, INC ]
