Adaptec 1542B User Manual - Page 14

Section Two Preparation and Configuration Floppy Enable - when installed, enables the floppy to respond to I/O writes and reads. Default is jumper installed, floppy enabled. If there is another floppy controller in the system, the floppy controller on the AHA-1542B can be disabled by removing this jumper. DREQ 2,3 - selects either DREQ 2 or 3 for floppy controller. At least one jumper must be installed for operation, and the corresponding DACK jumper must also be installed. Default is jumper in Pin Pair position 2, DREQ 2. DACK 2,3 - selects either DACK 2 or 3 for floppy controller. At least one jumper must be installed for operation, and the corresponding DREQ jumper must also be installed. Default is jumper in Pin Pair position 4, DACK 2. IRQ 6,10 - selects either interrupt channel 6 or interrupt channel 10. At least one must be selected for proper operation. Default is jumper in Pin Pair position 6, Interrupt Channel 6. Dual Speed - this jumper should be installed when a floppy drive with a dual speed spindle is used. For normal operation this jumper should not be installed. 2.3.4 SCSI Terminators RN2, RN3, and RN5 are the SCSI terminators. If both an internal and an external SCSI cable is used, then the farthest end of both the internal and the external cable should be terminated (either by terminators on a SCSI device or by passive terminators attached to the cable); all three terminators on the AHA-1540B/1542B must be removed. If an internal or an external cable is used (but not both) then the farthest end of that cable should be terminated and the terminators should remain installed on the AHA-1540B/1542B. Default is terminators installed. AHA-1540B/1542B 2-13 adaptec