The iOS application receives the same data from the printer multiple times Situation Although the printer only sends data (such as the status) once to the iOS device, the application on the iOS device may receive the data multiple times. Conditions If no data is sent between the printer and the iOS device for at least 30 seconds during Bluetooth connection, the iOS device switches to power-saving mode. This problem occurs if the printer sends data to the iOS device while it is in power-saving mode. The following are examples of when this occurs.
When the printer performs status communication with a command (DLE EOT, GS I, and so on) When the printer sends an ASB In the following situations, this does not occur. When the iOS device sends data to the printer When data is sent to the iOS device before it switches to power-saving mode (less than approx. 30 seconds) after the printer has received data from the iOS device When using the SDK from Epson (however, this may occur when receiving data from a printer using a com- mand transmission/reception API) Solution If no data is sent between the printer and the iOS device for at least 30 seconds, use the following steps to send data.
1) Before sending data, send 100 bytes of dummy data to the printer. As long as it is not related to printing or commands, anything can be used as the dummy data, however we recommend using 00h. 2) Set a waiting time of 100 milliseconds. 3) Send the data. The transmission distance is an estimate that depends on our experiment conditions and is not a guaranteed value. It varies based on the installation environment and target device. 110 NFC Tag Transmission standard ISO14443 A Frequency 13.56 MHz Memory 144 byte Transmission distance Approximately 10 mm from the NFC installation location.