Toshiba B-850 manual ECC0 ECC50 ECC80

(15)Explanation for Data Matrix c ECC type

Data Matrix contains a function to correct a code reading error using an error correcting code (ECC) and restore normal data. Since there are several ECCs, ECC should be designated according to usage. The general correction ability is as shown below. However, it may vary according to the error conditions.

ECC type	Error Correction Ability		Overhead by ECC
ECC0			0%
		Low
ECC50			25%
ECC80			33%
ECC100			50%
		High
ECC140			75%
ECC200			Approx. 30%

dFormat ID

Data Matrix can handle all codes including alphanumerics, symbols and Kanji. Since data compression rate varies according to codes, a code to be used is designated using the format ID.

Format ID	Code		Details
1	Numerics	0 to 9	space
2	Letters	A to Z	space
3	Alphanumerics, symbols	0 to 9	A to Z space . , - /
4	Alphanumerics	0 to 9	A to Z space
5	ASCII (7 bit)	00H to 7FH
6	ISO (8 bit)	00H to FFH (Kanji)

eMaximum number of digits

The maximum number of digits varies according to the ECC type or format ID. Since each Kanji character uses 2 bytes, the maximum number of digits for it becomes half of the following values.

	ECC0		ECC50	ECC80	ECC100	ECC140
Format ID 1	500		457	402	300	144
Format ID 2	452		333	293	218	105
Format ID 3	394		291	256	190	91
Format ID 4	413		305	268	200	96
Format ID 5	310		228	201	150	72
Format ID 6	271		200	176	131	63
		Numeric		Alphanumeric		8 bit
ECC200		2000		2000		1556

For the maximum number of digits in cell units, see the next page.

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