Mode 2 - Epson TM-P20 Technical Reference Manual

Mode 1
Battery LED
Level H
Level M
Level L
Level S
Level E
 Printing may be interrupted.
24
Remaining
Error LED
battery charge
Approx. 60  100%
Approx. 20  60%
Approx. 10  20%
Approx. below 10%
Approx. 0%
: On : Flash
Printing Communication
Possible Possible
Possible Possible
Possible Possible
Possible* Possible
Impossible Impossible
: Off