The Input/Output (I/O) Receiver module is utilized in all
I/O racks (except for the first I/O rack in a Remote I/O
station) to provide an interface for address, data, and control signals between the Series Six CPU and I/O modules;
it also provides a link in a daisy chain to other I/O racks.
The I/O Receiver module features and benefits are summarized in Table 1.
The I/O Receiver module monitors three types of error
conditions: Daisy-chain power and continuity of I/O racks
downstream (CHAIN OK); parity of data output by CPU
(LOCAL PARITY); parity of CPU output data, driven by
an I/O Transmitter module, as detected by other I/O Receiver module(s) downstream (CHAIN PARITY).
Corresponding LED indicators, visible through the
module faceplate, turn off when the module detects
errors and function as troublshooting aids.
The module comes from the factory configured for installation in all intermediate I/O racks in the daisy chain;
however, the user is instructed to reconfigure this
module to ensure proper termination of the I/O Bus if the
module is to be installed at the end of the I/O station daisy
chain. (Refer to NOTE on this page,)