Printer Initialization; Power On Initialization; Operator Initialization; Software Initialization - Epson Stylus Photo 870 Service Manual

EPSON Stylus Photo 870/1270
! Paper feed motor encoder sensor
The PF motor encoder sensor includes an encoder wheel attached
to the left end of the paper feed roller and a photo sensor. The
minimum resolution of the sensor is 1/180 inch. It outputs HIGH
signals for the black bands and LOW signals for the transparent
parts of the encoder wheel. The printer controls the paper feed
motor based on the signals output from this sensor.
! Carriage unit encoder sensor
The CR unit encoder sensor includes a photo sensor in the carriage
unit and an encoder strip. The minimum resolution of the sensor is
1/180 inch. It outputs HIGH signals for the black bands and LOW
signals for the transparent parts of the strip. The printer controls
the carriage motor based on the signals output from this sensor.
The sensor also lets the printer determine the carriage home
position.

2.5 Printer Initialization

The EPSON Stylus Photo 870/1270 printers use three different
initialization methods.

2.5.1 Power On Initialization

The printer is initialized when it is turned on or recognizes the cold-
reset command (remote RS command). It then does the following:
! Initializes the printer mechanism
! Clears the input data buffer
! Clears the print buffer
! Sets the default values

2.5.2 Operator Initialization

This printer is initialized when it is turned on within 10 seconds after
being turned off or it receives the /INIT signal (negative pulse) from the
parallel interface. It then does the following:
! Caps the printhead
! Ejects any paper in the paper path
! Clears the input data buffer
! Clears the print buffer
! Sets the default values

2.5.3 Software Initialization

The ESC@ command also initializes the printer and does the following:
! Clears the print buffer
! Sets the default values
Chapter 2 Technical Overview
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