Quatech DSP-200/300 - Manual (Page 10)

H instructs the client driver 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 DSP-200/300’s
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.
2.1.2.1 Example 1
DEVICE = C:\DSP-200\ DSP230CL.SYS
In example 1, no command line arguments are specified. The Client Driver will configure a
DSP-200/300 inserted into any socket with a base address and IRQ assigned by Card and Socket
Services. The DSP-200/300 RS-422/485 output drivers will always be enabled, and RTS-CTS
modem control handshaking will be disabled.
2.1.2.2 Example 2
DEVICE = C:\DSP-200\DSP230CL.SYS (b290,i11)
In example 2, a single command line argument is provided. The Client Driver will attempt to
configure a DSP-200/300 inserted into any socket with a base address of 290H and IRQ 11. If
address 290H or IRQ 11 is unavailable, the DSP-200/300 will not be configured. If the Client
Driver can successfully configure the DSP-200/300unit, the RS-422/485 output drivers will
always be enabled, and RTS-CTS modem control handshaking will be disabled.
2.1.2.3 Example 3
DEVICE = C:\DSP-200\DSP230CL.SYS(s0,b300,i5,o2)
In example 3, a single command line argument is provided. The Client Driver will attempt to
configure a DSP-200/300 inserted into socket 0 with a base address of 300H and IRQ 5. If
address 300H or IRQ 5 is unavailable, the DSP-200/300 will not be configured. In addition, if a
DSP-200/300 is inserted into any other socket, it will not be configured. If the Client Driver can
successfully configure the DSP-200/300, the RS-422/485 output drivers will be enabled and
disabled via the RTS signal, and RTS-CTS modem control handshaking will be disabled.
2-5 DSP-200/300 (Rev. I and later) User's Manual