Adaptec 1520A User Guide - Page 38

AHA-1510A/20A Series User's Guide Termination for External Devices Only When only external devices are connected to the host adapter, the last device on the external chain of devices should be terminated and the host adapter should be terminated, as shown in Figure 3-3. Host adapter Terminators installed External device No termination External device No termination External device Termination enabled Figure 3-3. Connecting External Devices Only Termination for Internal and External Devices When both internal and external devices are connected to the host adapter, the last external device and the last internal device should be terminated, and you should remove the three terminators (i.e., disable termination) on the host adapter, as shown in Figure 3-4. Internal device No termination Internal device Termination enabled Host adapter Terminators removed External device No termination External device No termination External device Termination enabled Figure 3-4. Connecting Internal and External Devices Caution: If you replace the host adapter terminators, make sure you maintain correct orientation. The dot on the upper left corner of the resistor must align with pin 1 of the socket. 3-4 AAAAAAAAAAAAAAAAAASPCAAAAAArtuHoiAAArncAAAArtkAAAe-SAAAn1NAAApt5AAAeuD1AAAcmAAA0aAAANtAbeAAAeu:/AAAr2mAAA1:0AAA15bAAAA/1eAAA1rAAA0S8:AAA4/e4AAA90rAAA94i0eAAA1-AAAs08AAAU04AAA,2AAAsR-AAAe0AAAre0'AAAvsAAA.AAAGCAAAuAAAAAAidAAAeAAAAAAAAAEAAACAAAAAANAAAAAADAAAAAAaAAAtAAAeAAA:PAAA1aAAA1AAAg/AAAe2AAA:9AAA3/AAA9-AAA44AAAAAAAAAAAAAAAAAAAA