SPM391PS is a Two-to-Four SATA RAID Controller. It integrated Port Selector, Port Multiplier and RAID processor to provide SATA port expansion, data protection, performance aggregation, and dual-host I/O control in various applications
SPM391PS provides four modes:
- PM (Port Multiplier) Mode
- RAID 0 Mode
- RAID 1 & RAID 10 Mode: RAID 1 (for two disks) and RAID 10 (for four disks)
- Large (JBOD) Mode
With an easy configuration scheme, the device can function as a pure port multiplier which provides SATA port expansion just like a SATA Hub, a hard drive performance booster which provides a high-performance device seen by the host controller, or a hard drive data protector which automatically backs up data to prevent data loss from hard drive damage.
The port selector enables two different hosts to control the four storage devices. The secondary host connection can be changed to use any one of several interfaces, such as 1394, USB, AOE, NAS, and others. The dual-host function may be used in storage subsystems, or for implementing a failover path in applications requiring redundancy. I/O priority is first given to the eSATA host; to enable control from the secondary host, the eSATA host must be disconnected.
SPM391PS also has an advanced mode to provide both the benefits of performance boost and data protection.
SPM391PS has a self-contained storage processor chip which completely frees up the main CPU loading and whose SATA ports comply with the eSATA specification, making it suitable for use in both internal system and external storage applications.
