I/O module for a serial multiplex data system with a programmable input voltage level selector
AssigneeSquare D Company
InventorRobert E. Riley
Life of this patent
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Abstract
A programmable data link module is used on a time division multiplex data bus. The module receives data from the data bus during a selected time slot for a selected number of frames. The data link module includes an input circuit for generating a data output signal data to the data bus in response to input signals from an input device coupled to the module. The input circuit includes a programmable input voltage level selector, allowing different voltage rated input devices to be used with the data link module. A hysteresis circuit sets a minimum voltage level threshold representative of the input device being in one logic state and a maximum voltage level threshold representative of the input device being in another logic state.
Claims10
An I/O module coupled to a data bus for use in a time division multiplexing control system, the I/O module including an input circuit for generating a data output signal to the data bus in response to input signals from an input device coupled to the I/O module, the input signal having an input voltage level range based on the input device having one of a plurality of voltage ratings, the I/O module comprising:
- A. an input terminal for receiving the input signal from the input device;
- B. a memory for storing one of a plurality of different input voltage levels acceptable to the I/O module;
- C. a programmable input voltage level selector to select an input device voltage level range from the stored plurality of different input voltage levels;
- D. a control circuit responsive to the stored input voltage level;
- and
- E. a logic circuit for producing the data output signal in combination with the stored one of a plurality of different input voltage levels and the received input signal being within the selected input device voltage level range.
Dependencies are inferred from the claim text.