04301507 is referenced by 123 patents and cites 10 patents.

An electronic postal meter has a control unit, an accounting unit and a printing unit, each incorporating a CPU having a separate crystal controlled clock. Communication between the units is serial character asynchronous, bit synchronous, in message form, with the bits of the messages being timed in accordance with a given schedule for synchronous control. The messages themselves, upon receipt by a receiver, are returned bit by bit to the transmitter, for checking, whereupon the transmitter sends a no-error pulse upon successful comparison of the transmitted message and the message received from the receiver. All control and data signals utilize the same pair of conductors in each direction with precisely defined timing for control.

Title
Electronic postage meter having plural computing systems
Application Number
6/89413
Publication Number
4301507
Application Date
October 30, 1979
Publication Date
November 17, 1981
Inventor
Robert B McFiggans
Stamford
CT, US
Alton B Eckert
Norwalk
CT, US
John H Soderberg
Monroe
NY, US
Agent
Albert W Scribner
William D Soltow Jr
David E Pitchenik
Assignee
Pitney Bowes
CT, US
IPC
G06F 15/16
G06F 15/20
G06F 15/02
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