Toshiba ATAPI Installation Manual page 9

Test Switches (T0, T1)
The leftmost two switches (a pair of pins makes one switch) are used during testing only.
These switches should always be OFF. The default setting for these switches is OFF.
Eject Suppression Switch (PRV/ALW)
The rightmost switch is used to inhibit the operation of the drive's EJECT button. When
this switch is set to ON, the EJECT button operates normally, opening the CD-ROM
tray. When the switch is OFF, the EJECT button cannot be used to open the drive. The
default setting for this switch is ON.
Master / Slave Switch
These switches are used to set the configuration mode for the drive:
Only one jumper should ever be fitted to this switch block. A computer which
communicates with its disk drives using an IDE controller may use two cables; the
primary cable and the secondary cable. Each cable may carry up to two drives; one
configured as a master drive and the other configured as a slave drive. The drives may be
either IDE hard disk drives or other IDE devices (in this case an ATAPI CD-ROM
drive):
The following table shows the recommended configurations. Check which configuration
your computer uses and set the configuration jumper on the drive accordingly. Refer to
8 TOSHIBA ATAPI CD-ROM Drive
Host
Primary cable
Master
Secondary cable
Master
Slave
Slave