Citizen LinkServer helps you to set up Citizen label printers via USB.

[Supported models]
Designated printer models, firmware versions are required (see below).
- CL-E300 (Firmware Version: EQxx0300 or later)
- CL-E300EX
- CL-E321 (Firmware Version: EQxx0300 or later)
- CL-E321EX
- CL-E303 (Firmware Version: ERxx0300 or later)
- CL-E303EX
- CL-E331 (Firmware Version: ERxx0300 or later)
- CL-E331EX
- CL-S521Ⅱ
- CL-S531Ⅱ
- CL-S621Ⅱ
- CL-S631Ⅱ
- CL-S700Ⅱ
- CL-S703Ⅱ

[Supported interface type]
- USB

The Android device must work as USB host to control the printer device. For example, you will need a so-called USB OTG (On-The-Go) adapter, which has a micro USB or Type-C male connector on the Android side (depending on your Android device) and a Type-A female connector on the other side. Then you can connect a regular USB cable for printer which has a Type-A male and Type-B male to connect to a printer.

[Example features]
- Checking printer information such as serial number or counters.
- Setting up printing controls such as printing speed, darkness or position.
- Setting up systems such as sensor levels or buzzer.
- Setting up media handlings such as cutter action.
- Setting up communication interface.
- Switching configuration presets.
- Managing access control.
- Printing test labels.
- Sending raw data to the printer.
- Updating firmware.
- Resetting the printer.
- Restarting the printer.
- Switching emulations.