Acer altos s300

7

I/O modules

There are two I/O option slots located at the rear of the enclosure.  
One of these must contain an Enclosure Services Module (ESM) 
or a Concentrator Services module (CSM) and the other slot must 
contain the Terminating Services Module (TSM) or a second 
Concentrator Services Module (CSM) for dual CSM configuration.

The I/O slot located on the left of the enclosure as viewed from the 
back is called I/O Slot A and the I/O slot located on the right is called I/O 
Slot B.  The I/O modules can be inserted into either of the I/O 
slots.

Note:  For a detailed information of the I/O modules, see page 20.

The following sections will describe the modules and how they should 
be used.

Enclosure Services Module 

The Enclosure Services Module (ESM) has three primary functions.  It 
acts as a SCSI bus pass-through from external cabling to the internal 
busses.  Secondly, it terminates the end of the SCSI bus in joined mode. 
Finally, it provides monitoring, reporting and control of the system 
storage enclosure.  The ESM reports status and receives control 
information via the SCSI bus per the SCSI-3 Enclosure Services 
specification and also the SAF-TE specification.

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I

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I/O Module

I/O Module

Mute

The I/O Modules can be inserted into either I/O slot