Troubleshooting example of POS swiping card-- failure of POS swiping card caused by inconsistent impedance

Reason: impedance leads to failure of POS card swiping

Failure phenomenon: swiping the card (query) successfully, the pos shows "connecting" for a long time in the process of swiping the card.

Device packet prompt message: media analysis on the pos side

Reason analysis: by parsing the packet information, there is an echo phenomenon in the pos signal. Because the pos service device needs to turn off the EC configuration, the echo caused by the impedance mismatch can not be eliminated, which interferes with the pos swiping card.

Treatment measures: confirm the device-side impedance configuration

Remarks: data services include low-speed data services (fax) and high-speed data services (high-speed fax, pos services, etc.). For high-speed data services, functions such as EC/VAD/CNG on the equipment side that may affect the original signal have little impact on low speed.

Examples of similar problems:

Reason: impedance mismatch

Failure: POS machine failed to connect to the server or failed to read the card after connecting to the server after swiping the card

Troubleshooting: analyze the media information of pos interaction and confirm the existence of echo phenomenon.