General Description

(1)Loop configuration

A port embedded with sending and receiving circuits uses differential signals to send and receive data on electric signal lines. A pair of signal lines is called a link. Since signals are sent in one direction on a link, the links in a system must be connected to form a loop. The FC-AL interface sends and receives data via nodes on the loop. Therefore, if a node connected to a loop is powered off or the interface signals of a node cannot be sent or received correctly, the loop does not work normally. A common solution preventing this problem from occurring is to add a port bypass circuit on the back plane of the system. BC in Figure 1.3 indicates the port bypass circuit.

(2)Node addressing

A specific device number called a SEL ID is assigned to each node on a Fibre Channel loop. The combination of signal levels on the back plane is used to define the SEL ID of a disk drive. The signal levels are sent on the seven signals (from SEL_0 to SEL_6) from CN1, which serves as an SCA interface connector. SEL_6 is the most significant bit (MSB), having a bit weight of the sixth power of 2, and SEL_0 is the least significant bit (LSB), having a bit weight of the zeroth power of 2. Any number from 0 (X’00) to 125 (X’7D’) can be assigned as the SEL ID of a disk drive.

1-8

C141-E163

Page 28
Image 28
Fujitsu MAP3147FC, MAP3735FC manual General Description

MAP3735FC, MAP3147FC specifications

Fujitsu has been a prominent player in the hard disk drive market, with its MAP3147FC and MAP3735FC models standing out in terms of performance and reliability. These drives are engineered to meet the growing demands of enterprise applications, providing robust solutions for data storage in critical environments.

The Fujitsu MAP3147FC, with a capacity of 147 GB, is optimized for high-speed data access and storage efficiency. This 3.5-inch SCSI drive operates at a rotational speed of 15,000 RPM, ensuring rapid data retrieval and minimized latency, making it ideal for applications requiring quick transaction processing. It features a 4 Gbps Fibre Channel interface, which enhances connectivity and system integration, promoting seamless communication between devices in storage area networks.

On the other hand, the MAP3735FC model offers a higher capacity of 300 GB. It shares similar specifications with its counterpart, including the 15,000 RPM speed, which guarantees top-notch performance for mission-critical applications. The MAP3735FC, like the MAP3147FC, incorporates advanced technologies such as Command Queuing, which optimizes the execution of multiple read and write commands in a queue. This feature is particularly beneficial in environments with high I/O demands, improving overall system throughput and efficiency.

Both drives utilize sophisticated error correction techniques, ensuring data integrity and reliability. They are equipped with features like S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology), which continuously monitors the health of the drives and helps predict potential failures, allowing for proactive maintenance and data protection.

In terms of physical characteristics, both models are designed to withstand the rigors of continuous operation. They are built with a rugged casing to protect against vibration and shock, making them suitable for use in enterprise-level servers and storage systems. Their design also allows for efficient heat dissipation, which is critical for maintaining optimal performance during extended use.

In summary, Fujitsu's MAP3147FC and MAP3735FC hard drives embody a combination of high speed, reliability, and advanced features tailored for enterprise environments. Their robust performance, large storage capacities, and reliable error correction technologies make them an excellent choice for businesses looking to optimize their data storage solutions and ensure seamless operation in demanding applications. With Fujitsu's commitment to quality and innovation, these models continue to meet the evolving needs of the data storage industry.