Quatech SSP-200, Руководство пользователя

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CC, D0, D4, D8, and DC. If this option is omitted, a memory window at segment
D000 will be used.
Odriver specifies RS-422/485 output driver enable option for theSSP-200/300. The
SSP-200/300’s port may be configured for either full duplex or half duplex
operation with this option. If this option is omitted, the default setting is the
RS-422/485 port is configured for full duplex operation with the RS-422/485 output
drivers always enabled. In half duplex mode, the RS-422/485 transmitter may be
enabled and disabled via the RTS (request to send) or DTR (data terminal ready)
signals. Both RTS and DTR are controlled through the Modem Control Register of
the 16750. See the
Hardware Information section for more information.
Auto-toggle o3
RTS Controlled o2
DTR Controlled o1
Always Enabled o0
Output Driver Option
Figure 0. DOS Enabler Output Enable Options.
H instructs the enabler to enable the RTS-CTS modem control handshake on the
RS-422/485 port. When modem control handshaking in enabled, the 16C750
UART’s RTS and CTS signals are connected to the RS-422/485 auxiliary channel.
The auxiliary channel may then be used for handshaking between the SSP-200/300’s
RS-422/485 port and a peripheral device. When modem control handshaking is
disabled, the RTS and CTS signals from the 16C750 UART are looped back to each
other. If this option is omitted, the default setting is RTS-CTS modem control
handshake disabled. See the
Hardware Information section for more information .
Before removing a SSP-200/300 from its PCMCIA socket, the Enabler should be executed to
free the system resources allocated when the card was installed. For this operation the Enabler
provides on additional command line option:
R instructs the enabler to release the resources previously allocated to the SSP-200/300
. When the 'R' option is used, any settings specified by the 'B', 'I', 'O', and 'H' options
are ignored.
DOS/Windows 3.x 2-10