Hand Held Products IT4800 Bar Sequence, Codeword Data and Check, Codeword Yield, Edge Accuracy

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Bar Sequence

Bar Sequence

Bar Sequence is the bar height pattern within a height modulated, multi-state, postal-type symbology. In a 2-state symbol, a "1" represents a tall or full height bar and a "0" represents a short or half height bar. In a 4-state symbol, "A" rep- resents the ascending bars, "D" the descending bars, "T" the short bars, and "H" the tall bars that both ascend and descend. Incorrect sequencing can be sys- tematic and can be caused by the symbol generating program not meeting requirements.

Codeword (Data and Check)

A Codeword is a symbol character value or intermediate level of coding between source data and the graphical encodation in the symbol. A data code- word encodes data according to the rules or scheme of the symbology, where check codewords are reserved for error detection/correction purposes.

Codeword Yield

Codeword Yield is an indication of the interference between adjacent rows in a 2D stacked symbology. A low Codeword Yield can indicate print conditions where this interference is caused by drag, streaking, or other situations where there is carry-over of ink from one row to another (see "Useful Row Height" on page 1-19).

Data Safety Margin

Data Safety Margin is the ratio of the unused error correction codewords to the recommended number of error correction codewords. A low Data Safety Mar- gin indicates a symbol that is close to reading failure and can be improved by improving the printing, correcting the cause of bad or missing symbol characters (e.g., spots, voids), or by raising the Error Correction Level (ECL).

Edge Accuracy

Edge Accuracy is a measure of the accuracy of the bar or dark element edge positions within the symbol. A low Edge Accuracy indicates print conditions, such as a "print pitch to X-dimension" mismatch or general edge irregularities (but not uniform print growth), which can harm character decoding. The first condition is improved by properly scaling the symbol to the print pitch, and both conditions are improved by making the symbol larger.

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Contents Quick Check 2D Print Quality Assessment User’s GuideDisclaimer Table of Contents Chapter 1 - IntroductionChapter 3 - Customer Support Chapter 2 - Quick*ViewSymbology X-dimensionIntroduction User OperationReading Techniques Symbology/Parameter Specifics 2D PQA Reporting Full ReportScreening Report This is a representative PDF417 symbol PQA from HHP Identifying Symbol ContentA Data Safety Margin = 100% 0 Erasures & 0 Errors PDF417 11 rows x 3 cols, 25 data & 8 chks ECL = 2 X roughly =2D Stacked / Multi-row PDF417Excessive Print Shrinkage -43% of where In Screening modes, this parameter is reported as Useful Row Height is Too Short 1.5X when that is the case 1 is the Encoded Message MicroPDF417Aztec Code 2D Matrix1 This is a representative Data Matrix symbol 2 PQA from HHP Data Matrix6 A Fixed Patterns 0 module errors 3 DATA MATRIX ECC200 24 x 24 modules in sizeQR Code 7 A Data Safety Margin = 100%1 This is a representative QR Code symbol 2 PQA from HHP 4 lists this symbols Mask Pattern and Error Correction Level MaxiCodePostnet and Planet Code Postal Height-Modulated Bar Code Symbologies7 A Ok Bar Widths = 0.022 in 8 A Ok Inter-Bar Gaps = 0.023 in 1 B15AJ6T 2 PQA from HHP 4-State Codes3 4-STATEBritish 34 Bars, nominally from 38.5 to 42.3 mm. in Width 4 Bar Sequence ADHTATDAHDDAADADAADTHTADHHDATHTADHAverage Bar/Gap Width Parameter InterpretationAverage Bar Height/Extension Height Table 1 Dimensional Tolerances for the Various 4-State BarBar Sequence Data Safety MarginCodeword Data and Check Codeword YieldError Correction Level ECL Error Correction/Error Correction CharactersError Detection/Error Detection Characters Encoded MessageSymbology Module ErrorsPrint Growth Horizontal and Vertical Row HeightX-dimension Setting Up the Imager and the Quick*View Software Installing Quick*View from the WebQuick*View Quick*View Demonstration Software InstructionsTemporary Quick*View Configuration IT4600/4800/4X80IT4410/4710 If Communication Cannot Be Established Using the Quick*View SoftwareScan Data Window Customer Support Obtaining Factory ServiceNorth America Latin AmericaTechnical Assistance North America/CanadaAsia Page QC2DPQA-UG Rev B
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