HARDWARE PREPARATION AND INSTALLATION
2-24
M68HC11EVBU/D
A Hayes compatible modem cable, purchased from your local computer store, can be used to
connect the EVBU to your host computer.
The EVBU is wired as data communication equipment (DCE) whereas a dumb terminal and most
serial modem ports on host computers are wired as data terminal equipment (DTE). This should
allow a straight-through cable to be used in most setups.
If an unknown cable is used to connect the EVBU to a host computer, a null modem adapter
(shown below) may be required to match the cable to the EVBU terminal port connector.
A null modem adapter is used to reverse the roles of various data and control signals to make a
DTE device appear as a DCE device or vice versa.
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2
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7
8
20
1
2
3
4
5
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8
20
DB-25S
DB-25P
NULL MODEM ADAPTER
GND
TXD
RXD
SIG-GND
CTS
DSR
DCD
DTR
RTS
GND
TXD
RXD
RTS
CTS
DSR
SIG-GND
DCD
DTR
Summary of Contents for M68HC11EVBD
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