Circuit; Localtalk Circuit - Epson ActionLaser 1600 Service Manual

Circuit

RS-422
This circuit uses the RS-422 receiver/driver IC MC34050 (IC6) to change the
signal level from the RS-422 signal level to the TTL signal level (0 V or +5 V) or
from the TTL signal level to the RS-422 signal level. The E05A93 standard cell
changes serial (RS-422) data to parallel data.

LocalTalk Circuit

The LocalTalk circuit is an optional I/F board that uses three ICS, 85C30 (IC3),
26LS30 (IC1), and 26LS32 (IC2). The 85C30 (IC3) changes parallel data to serial
data or serial data to parallel data. It is controlled by the E05A93 (IC24) on C125
MAIN board. The 26LS30 (IC1) and 26LS32 (IC2) are ICS used to change signal
levels from the TTL signal level to LocalTalk signal level (compatible with RS-422
signal level).
EPSON ActionLaser 1600 Service Manual
Figure 2-43. RS-422 Circuit
Figure 2-44. LocalTalk Circuit
Principles of Operation
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