Quatech QSP-200/300 - Manual (Page 42)

6.3 Auxiliary Channel Configuration
An auxiliary channel is provided which allows for handshaking between a QSP-200/300
RS-422/485 port and a peripheral device. This auxiliary channel may be configured in one of
two ways:
Ÿ RTS-CTS handshake enabled.
Ÿ handshaking is disabled.
All ports must be configured in the same manner.
6.3.1 Auxiliary Channel: RTS-CTS Handshaking
The RTS-CTS handshake may be enabled so that RTS (Request To Send) is the auxiliary output
signal on AuxOut+ and AuxOut- (pins 1 and 6 of the D9 female connector). Similarly, CTS
(Clear To Send) is the auxiliary input signal on AuxIn+ and AuxIn- (pins 5 and 9 of the D9
female connector). This configuration is shown below.
RS-422/485
+
+
+
+
-
-
-
-
16C550
UART
DATA OUT
DATA IN
AUX OUT
AUX IN
TXD
RXD
-RTS
-CTS
Drivers/Receivers
Driver
Receiver
Driver
Receiver
Figure 5. Auxiliary Channel RTS-CTS Handshaking.
QSP-200/300 User's Manual 36