PM8379 CTS 20x4G

• 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).

The CTS 20x4G is designed to interface directly to Fibre Channel disk drives in a storage array.  PM8379 CTS 20x4G 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 of PM8379 CTS 20x4G 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 of PM8379 CTS 20x4G 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.