Oki OKIPAGE 14, Руководство по обслуживанию

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41356801TH Rev.1
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2.3.4 Revision of LED Head Illumination
An LED correcting head, which is capable of correcting the illumination of the LED for each dot, is being
used in this printer. LED illumination correction function of 16 steps is carried out by using an EEPROM
which is installed in the LSI that maintains the LED illumination correction values, and an LED correction
drivers together as a pair.
The printing and correction data obtained from the CPU through four signal lines are sent to the LED
array.
The printing operation timing chart is shown below.
The printing operation is carried out in normal mode. Under ordinary circumstances such as when the
power is turned on or when LOADI signal level is low, the normal mode is enabled.
The printing operation is carried out in the following sequence. First, the printing data DATAI3 through
DATAI0 are stored, sequentially shifted, in the shift registers of the LED drivers, by the printing data
synchronous clock, CLOCKI. Then the printing data stored in shift registers are latched by the high level
pulse of LOADI. The latched printing data turns the LEDs on by STRB1I-N through STRB4I-N and
actuates printing.
CLOCKI
LOADI
DATAI3~0
STRB1I-N
STRB2I-N
STRB3I-N
STRB4I-N
Normal Mode Printing Timing Chart
First line printing data sent Second line printing data sent
First line printing