Measurement Computing Extender488 - Manual (Page 18)

Section 2 Getting Started
2. 8
If any of the symptoms shown occur, cycle the power switch on the Extender488 to be sure of the
problem. If the problem is unresolved, refer to the Service Information section of this manual.
WARNINGThe Extender488 makes its earth ground connection through the I EEE
interface cable. Each extender must be connected to at least one IEEE device which
is earth ground referred. Failure to do s o may allow the Extender488 to float to a
voltage away from ground. This co uld result in damage to the interface, personal
injury or death.
If proper operation is obtained, turn-off the Extender488 power switch and connect the other IEEE
devices to each of the Extender488's IEEE ports. Connect the local extender to the remote extender via the
serial or fiber optic cable. Apply power to all devices in the system. If the Extender488 ERROR LED
continues to blink after the power-on sequence, this indicates one of two possible conditions: either the
system controller has not yet asserted the Attention line, or communication with the mating extender has
not yet been established. B e sure both extenders are powered-on, the cabling has been installed, and the
controller has asserted Attention before assuming there is a problem.
Once all IEEE devices have been connected and powered on, the Extender488 will allo w the
system controller to co mmand up to 13 IEEE devices on its local b us (in addition to itself and t he local
extender), and up to 14 IEEE devices on the remote bus (in addition to the remote extender). The extenders
have no address of their own, and therefore will operate
completely transparent to the system (with the
exception of parallel poll). Be careful not to have two IEEE devices with the same address connected to
either remote or local buses. Failure to do so will result in the bus 'locking up' when one of the devices is
accessed.