Ming Zhang Chen

US Patent:

57107556, Jan 20, 1998

Filed:

Nov 15, 1993

Appl. No.:

8/152614

Inventors:

Ming C. Chen - Shelton CT

Assignee:

Pitney Bowes - Stamford CT

International Classification:

H04L 1240
H04G 902

US Classification:

370 24

Abstract:

The communication system is a cyclic, serial, multi-drop, master-slave, half-duplex protocol having data formatted into receive frames and transmit frames carried on separate wires. Both receive frame and transmit frame have the same structure and are synchronized with each other. Each frame comprises a flag byte followed by 8 device channels, each channel comprising 3 bytes space. The flag byte is used as a reference for frame synchronization. Physical connection is by way of two half duplex RS-485 multipoint links utilizing telephone cable for connection between devices.

US Patent:

57082618, Jan 13, 1998

Filed:

Oct 2, 1995

Appl. No.:

8/537967

Inventors:

Ming C. Chen - Shelton CT

Assignee:

Pitney Bowes Inc. - Stamford CT

International Classification:

G06K 710

US Classification:

235463

Abstract:

A method for dynamically establishing a plurality of threshold values for use in decoding a bar code symbol having a plurality of characters where each character includes a plurality of wide and narrow elements. Additionally, the symbol also includes a first character having elements of known sequence and type. The method comprising the step(s) of: (a) keeping an indicator of an amount of time that a light source from a scanner system illuminates a selected element from the first character, (b) establishing a current threshold value based upon the selected element indicator for use in decoding a second element, (c) keeping an indicator for each of the plurality of elements of an amount of time that the light source from the scanner system illuminates the plurality of elements, respectively, and (d) adjusting the current threshold value using the indicators before decoding a subsequent element.