1.3 System Configuration

(6)Read/write circuit

The read/write circuit utilizes a read channel mounted with a head IC that supports high-speed transmission and an MEEPR4ML (Modified Enhanced Extended Partial Response Class 4 Maximum Likelihood) modulation/demodulation circuit in order to prevent errors being triggered by external noise and to improve data reliability.

(7)Controller circuit

The controller circuit uses LSIs to increase the reliability and uses a high speed microprocessing unit (MPU) to increase the performance of the SCSI controller.

1.3System Configuration

For the Fibre Channel, the ANSI standard defines Arbitrated Loop, Fabric, and Point-to-Point technologies. The MAS series disk drives support the Arbitrated Loop technology. Figure 1.3 gives an example of the FC-AL system configuration.

Port B

Initiator

(Node-1)

Port A

Port B

Drive

(Node-4)

Port A

BC

BC

BC

BC

BC

BC

BC

BC

Port B

Drive

(Node-2)

Port A

Port B

Drive

(Node-3)

Port A

Figure 1.3 Example of FC-AL system configuration

Any device connected to the Fibre Channel is called a node. The nodes shown in Figure 1.3 represent the initiator and individual disk drives. Each node has at least one port called an N_port. For FC-AL, each port is called a Node-Loop port (NL_port).

The MAS series disk drive has two ports, one of which is used for connections to an FC-AL. A maximum of 126 NL_ports can be connected to a single port.

C141-E198

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Fujitsu MAS3735FC, MAS3367FC manual System Configuration, Example of FC-AL system configuration