MULTIPLEX EXTENDER FOR DISCRETE I/O DEVICES ON A TIME DIVISION NETWORK

摘要

A multiplex extender (26) for permitting discrete I/O devices (34) to be multiplexed on a time division multiplexed control bus (10) includes a multiplex channel address decoder (78) to produce one or more output signals, each being determined by the multiplex channel address most recently decoded, a data disconnect switch (82) to either pass or block the flow of data between the TDM control bus (10) and the discrete I/O devices (34) in response to the output signal from the adress decoder (78), a data latch/repeater (86) to selectively store data from the TDM control bus (10) or repeat previously stored data to the discrete I/O devices (34), and a branch line controller (90) to transmit the previously stored data from the data latch/repeater (86) to the branch line (30) when the data disconnect switch (82) is blocking data frames from the TDM control bus (10).