Epson C11C605001 - DFX 9000 B/W Dot-matrix Printer, Руководство по обслуживанию

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Operating Principles
2.2.1.5
Parallel Interface Circuit
Figure 2-41 shows the parallel interface circuit block diagram. Data sent from the host is
latched within the by the STROBE
signal.
The outputs the
BUSY signal
automatically to stop the host computer from sending additional data. The CPU
resets the
BUSY
signal after reading the data from the so that the printer is ready to receive more data from
the host computer.
——————b
Latch
1-” ”-:
Figure 2-41. Parallel Interface Circuit
2.2.1.6 Circuit
This circuit uses the receiver/driver to change the signal level the
signal level (-12 or to the signal level (O V or +5 V) or from the
signal level to the signal level. co5 to +12 and –12
The standard cell changes serial data to parallel data.
serial
Data
Transmit
Parallel Data -.................. ------”--”-b
MA)(2O2
Figure 2-42. Circuit
.-., ..,
.
-’
2-28
Rev.