Z80 Datasheet, PDF (322/330 Pages) Zilog, Inc. – Z80 CPU PERIPHERALS

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RSXYZ
Drivers/
Z80
Receivers
SIO
Z80
CPU
Z80
CPU
Z80
SIO
RSXYZ
Drivers/
Receivers
RSXYZ
Drivers/
Z80
Receivers
SIO
Z80
CPU
Figure 125. Synchronous/Asynchronous Processor-to-Processor
Communication (Direct Wire to Remote Locations)
Figure 126 illustrates how both channels of a single Z80 SIO are used with
modems that have primary and secondary or reverse channel options.
Alternatively, two modems without these options can be connected to the
Z80 SIO. A correct baud-rate generator (Z80 CTC) must be used for asyn-
chronous modems.
Z80
CPU
Primary
Channel
Ch.A
Z80
SIO
Ch.B
RS
Driver/
Receiver
Secondary
Channel
Modem
(SYNC or
ASYNC)
Data Link
to Remote
Processor
Figure 126. Synchronous/Asynchronous Processor-to-Processor
Communication (Using Telephone Line)
Figure 127 depicts the Z80 SIO in a data concentrator, a relatively
complex application that uses two Z80 SIOs to perform a variety of func-
tions. The data concentrator can be used to collect data from many termi-
nals over low-speed lines and transmit it over a single high-speed line after
editing and reformatting.
UM008101-0601
Serial Input/Output