The ST01 and ST02 Host Adapters provide an 8-bit SCSI interface for the IBM PC, XT, AT (and all 100% compatible systems) and up to seven SCSI devices. Installation of more than two hard disc drives requires device driver software, which is not provided by Seagate.

 

The ST02 additionally supports up to two 3.5-inch or 5.25-inch floppy diskette drives.

 

Seagate SCSI Host Adapters require only a single bus connector and may be installed in a standard IBM PC short or long slot.

 

Host Adapter Configuration Jumpers:

 

·        Starting BIOS Address, ST01 and ST02:

 

C800H is the 16K BIOS address (default). For the 8K BIOS, the default address is A00H. If there is a board already installed at the default address in the system, use the jumpers to change to another address. Refer to Figure 1.

 

·        Zero-Wait-State (0WS), ST01 and ST02:

 

A 2-pin jumper is provided to enable the 0WS logic for PC ATs and compatibles that implement the 0WS control line on the PC bus. The default configuration disables the use of this line.

 

Optimum performance will be achieved, on PC AT compatibles that correctly implement this signal, by enabling this line.  Please consult your system manual or contact your dealer for more information.

 

·        Interrupt Selection, ST01 and ST02:

 

A 3-pin jumper is provided in order to select interrupts. Interrupts should be disabled (by removing the  jumper) for PC/MS-DOS operating in PC XT AT environments. This is the default configuration. 

 

·        Diskette Drive Selection, ST02 Only:

 

The ST02 supports all four of the standard PC diskette drive types. A jumper is provided (JP5) to restrict diskette support PC XT functionality; that is, only 360 KByte and 720 KByte. The default setting (jumper on) will support all types. 

 

·        Register Emulation, ST02 Only:

 

Many personal computers that are compatible with the IBM PC AT check at boot time to verify that an AT-compatible diskette/hard drive controller is present. If not, then an XT-compatible diskette controller is assumed and only 360 KByte diskette drives are supported.

 

A jumper is provided to enable emulation of this register (01F4H). 

 

The default is to enable emulation. In PC and PC XT environments, it is not used and may be safely left installed. It should be used in PC AT compatible systems; removing the jumper may prevent use of 1.2 MByte and other (non-360 KByte) format diskette drives.

 

Emulation should be disabled if the system already has a hard disc controller installed.

 

Seagate ST02 SCSI Host Adapter
 

 

·  J2: Internal SCSI Connector 

·  J3(Early): Internal XT-type Floppy Connector 

·  J5(Early), J3(Late) Internal AT-type Floppy Connector 

·  J7(Early), J5(Late): Hard Drive LED Connector 

·  J4: Aux Power Connector