Confidential
EPSON
TITLE
SHEET
REVISION
NO.
SHEET
NEXT
B
RP-U420 series
Specification
(STANDARD)
44
43
3.8 Paper Detectors
The printer has the following paper detectors:
•
Paper roll near-end detector
•
Validation detector
3.8.1 Detectors and LED indicators
1) Paper roll near-end detector (Receipt and Journal)
This sensor is installed on the paper roll supply device. It detects a paper near-end by monitoring
the paper roll diameter. The PAPER OUT LED lights when the paper roll diameter becomes
sufficiently small.
2) Validation detector
This sensor detects a validation paper inserting.
When a validation is selected as a paper source and the printer waits for the validation to be
inserted or removed, the PAPER OUT LED blinks. (Refer to Table 3.4.1)
3.8.2 Detectors and printing
When the printer detects a paper near-end, it stops or continues printing, depending on the ESC c 4
command setting.
3.9 Buffer-full Printing
When subsequent data is received after the printer processes one line of data in the print buffer, the
printer automatically prints the processed line and feeds the paper by one line.
