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.
