IoT Services

ABOUT principle of barcode scanner

Firstly, principle of 1D and 2D barcode

About the principle of 1D barcode:

--It is made up by strip and space, which is recognized with the principle of the difference between the reflectivity of strip and space to light.

--It only contains few information, most of them are number, signal and letters.

About the principle of 2D barcode:

--It is made up by geometric drawing with certain rules.

--It is scanned with picture, which could be recognized without printing.

--It contains lot of information, which could contain number, signal, letter and Chinese character.

Secondly, difference between scan head of 1D and 2D barcode

--2D barcode scan head scan the barcode with picture, with function of camera.

--2D barcode scan head could scan 2D and 1D code, with almost same speed to 1D scan head.

Thirdly, classification of normal barcode

--About 1D barcode system, there are  EAN-13, Code 128, Code 39, Interleaved 2 of 5, UPC-A, UPC-E, EAN-8, Code 93, Code 11, Codabar, Discrete 2 of 5, Chinese 2 of 5, MSI and RSSI.

--About 2D barcode system, there are  QRCode, PDF417, DataMatrix, Aztec Code, MaxiCode, MicroPDF417, OCR-A, OCR-B, MiroQRTCIF Linked Code 39(TLC 39) and Inverse 2D.

Problems and solutions of AUTOID barcode scanner

Phenomenon 1: Before three problem barcode could not be scanned.

Solution: AUTOID Handheld terminal supplied by SEUIC will check that if need to read it under the LED light source or not, if the barcode reading is insensitive. If it could not be scanned even meet the before condition, it should set the security level of the handheld terminal to 1 and turn off the other redundancy settings, which could scan the problem barcode.

Phenomenon 2: Produced barcode may check bit error, because some software is not specification, if the scan head needs to check, it will be unable to scan.

Solution: First, to regenerate the barcode according to the specification. Second, turn off the checking function of scan head, but may result in scanning error.

Phenomenon 3: One or more bits out of the barcode

Solution: Check the classification of barcode, then turn on or off the check code.

Phenomenon 4: The first bit of UPC-A barcode is not displayed.

Solution: In UPC-A barcode, the fist is country number, second is the system signal. The country number should be set as UPC-A modified to add country number and system signal.

TRANSMISSION PROTOCOLS:

CDMA EvDO Rev. A » GSM/GPRS