Epson Mobilink TM-P20II Technical Reference Manual page 68

In 1 and 2, the following guidances are printed, the Power LED flashes, and instructs the user's operations.
1. Continuing self-test guidance
2. Mode selection guidance
Wi-Fi model
Mode Selection
Modes
0: Exit and Reboot Printer
1: NV Graphics Information
3: Customize Value Settings
4: Restore Default Values
5: Interface Setup
8: Radio Field Intensity Check
More than above: None
Select Modes by executing following
procedure.
step 1. Press the Feed button less
than 1 second as many times
as the selected mode number.
step 2. Press Feed button for 1
second or more.
Chapter 4 Advanced Usage
Bluetooth model
Mode Selection
Modes
0: Exit and Reboot Printer
1: NV Graphics Information
3: Customize Value Settings
4: Restore Default Values
5: Interface Setup
More than above: None
Select Modes by executing following
procedure.
step 1. Press the Feed button less
than 1 second as many times
as the selected mode number.
step 2. Press Feed button for 1
second or more.
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