REV.-A
2.3.6
Drive Circuit
Figure 2-24 shows the
drive circuit in block diagram form. The print data already has been
expanded to create the image data. The CPU splits up this data three times and transfers this information
to the latch circuit within the
The CPU samples the voltage of the +35 V line via the A/D
convertor (see Section 2.3.3).
The CPU outputs a pulse via the CPU time output port
The length of this pulse corresponds to
the voltage of the +35 V line. This pulse becomes the head drive signal. In this way,
outputs
head drive signals (signals HD 1 to
that relate to voltage levels through the length of the pulses.
These signals are output to the head for each of the sections of print data that were created by
subdividing the data three times before sending.
By sampling the +35 V line voltage and determining the length of the head drive signal, it is possible
to maintain the energy supplied to the head at a constant level. If the voltage of the +35 V line is HIGH,
the CPU shortens the output pulse. If the voltage of the +35 V line is LOW, the CPU lengthens the output
pulse.
Figure 2-25 shows the timing of-the output of the head drive signal.
CPU (Ic)
DO-7
.
E 0 5 A 5 0
DO-7
HD 1-24
Figure 2-24.
Drive Circuit
CPU
O u t p u t
r - - - - - - - - - -
1
1
t
1
L - - - - - - - - - -
J
L - - - - - - . - - - - J
Figure 2-25. Head Drive Signal Output Timing
2 - 1 9
Summary of Contents for LQ-1070+
Page 1: ...EPSON TERMINAL PRINTER LG1 570 lo7cJ L 4000566 REV B ...
Page 111: ...REV A Figure 6 2 LQ 570 Lubrication Points 6 3 ...
Page 112: ...REV B 6 4 ...
Page 125: ...REV B C3 11 C9 I 1 Figure A 10 BOARD ASSY POWER SUPPLY C062 PSB BOARD Component Layout A 1 3 ...
Page 127: ...REV B Zluo Zr Vlr alr Figure A 1 2 BOARD ASSY PANEL C062 PNL BOARD Component Layout A 1 5 ...
Page 128: ...Figure A 1 3 LQ 570 Exploded Diagram A 1 6 ...
Page 129: ...REV B A 1 9 ...
Page 133: ... I C 71 I Ila u 4 l t mm 151 m Figure A 1 8 LQ 107O Case Outline Drawing A 23 ...
Page 135: ...EPSON Printed in Japan 91 09 5 G ...
