User`s manual

52 www.rabbit.com EM1500 Configuration
• When connected
• Inactive - never asserted
• When not in Hayes-modem command mode
NOTE: for SER2, this is DSR control.
1
RTS Control
1
Specify how to use the RTS modem control line. This is only applicable if the line is
not being used for hardware flow control, and the serial port has modem control lines.
The choices are:
• Active - always asserted
• When connected
• Inactive - never asserted
NOTE: for SER2 this is CTS control.
1
DCD Control (for SER2 only)
Specify how to use the DCD modem control line. This is only applicable if the line is
not being used for hardware flow control.
The choices are:
• Active
• When connected
• Inactive
RI Control (for SER2 only)
Specify how to use the RI modem control line.
The choices are:
• Inactive
• Pulse for 1 second when connection first established
5.1.6.1 Modem Tab Parameters for SER3 and SER4
The configuration parameters available on the Modem tab for SER3 and SER4 differ from the other serial
ports for several reasons. First, although SER3 and SER4 are 3-wire RS-232 ports by default, they can be
changed to have TTL-level signals by changing jumpers on JP2 or JP3 respectively. Second, SER3 is con-
figurable as a 5- or 9-wire port. Either of these configurations preclude the use of SER4 as a 3-wire port.
Third, in a future release of the EM1500, an internal modem will be available that will use SER4 even
when SER3 is configured as a 5- or 9-wire port. The configuration program refers to this future option on
the Modem tab for SER3 and SER4; however, it is not currently available.