(16) Explanation for the PDF417 and MicroPDF417

cSecurity level

The PDF417 contains a function to correct a code reading error using an error correcting code word and restore normal data. The security level should be designated according to usage to perform the error correction function.

For the MicroPDF417, the printer sets the security level automatically.

Security level

Error Correction Ability

No. of error correction

code words

 

 

 

 

 

 

 

 

 

Level 0

 

 

 

0

 

Low

 

Level 1

 

 

2

Level 2

 

 

 

6

Level 3

 

 

 

14

Level 4

 

 

 

30

Level 5

 

 

 

62

Level 6

 

 

 

126

Level 7

 

High

 

254

Level 8

 

 

 

510

 

 

 

dNo. of columns (strings)

The number of rows are variable in the PDF417. The row length (No. of data strings) is also variable. Therefore, a symbol can be created in a form that can be easily printed, by changing the proportion of the height and width.

The number of columns (data strings) is varied between 1 and 30.

If the number of columns is too small when th data amount is large and the security level is high, drawing may not be performed. This is because the number of rows exceeds 90 when the number of columns becomes small. (When the PDF417 is used, the number of rows of symbols is limited from 3 to 90.)

For the MicroPDF417, not only the number of columns (data strings) but also the number of rows (data lines) can be designated. When these are to be designated, see the table on page 100. Note that the max. number of digits for the set parameter (gg) varies according to the character type. If data over the max. number of digits for the set parameter (gg) is set, the bar code is not printed. The number of columns (data strings) is varied from 1 to 4.

However, the max. number of lines, which is 44, depends on the number of columns.

(17)Explanation for QR code c Error correction level

The QR code contains functions to detect and correct an error. If one of the data characters is damaged, the information can be restored when this code is read.

There are 4 levels that can be designated. The level should be specified according to usage. The general correction ability is as follows.

Level

Error correction ability

Overhead by correcting

 

 

an error

 

 

 

High density level

Low

7%

 

 

 

Standard level

 

15%

 

 

 

Reliability level

 

25%

 

 

 

High reliability level

High

30%

 

 

 

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Image 137
Toshiba B-SX4T-GS20-QM-R manual