Rockwell Automation DAG6.5.8 APPLICATION GUIDE SCADA SYSTEM - Manual (Page 167)

Publication AG-UM008C-EN-P - February 2005
Configuring SLC 5/03, 5/04, and 5/05 Processors 4-29
Chan. 0 System Control Line No Handshaking This parameter defines the mode in which the driver operates.
Choose a method appropriate for your system’s configuration:
•
If you are not using a modem, choose NO HANDSHAKING.
•
Half-Duplex with Continuous Carrier
(1)
•
Half-Duplex without Continuous Carrier
(1)
See page 4-5 for descriptions of the control line operation settings.
Error Detection CRC With this selection, you choose the how the processor checks the
accuracy of each DF1 packet transmission.
BCC: This algorithm provides a medium level of data security. It
cannot detect:
•
transposition of bytes during transmission of a packet
•
the insertion or deletion of data values of zero within a packet
CRC: This algorithm provides a higher level of data security.
Select an error detection method that all devices in your
configuration can use.
When possible, choose CRC.
RTS Off Delay (1) 0 Defines the amount of time, in 20 millisecond increments, that
elapses between the end of the message transmission and the
de-assertion of the RTS signal. This time delay is a buffer to make
sure that the modem has transmitted the message, but should
normally be left at zero. See page 4-8 for further guidelines for
setting this parameter.
RTS Send Delay
(1) 0 Defines the amount of time, in 20 millisecond increments, that
elapses between the assertion of the RTS signal and the beginning of
the message transmission. This time allows the modem to prepare to
transmit the message. The Clear-to-Send (CTS) signal must be high
for transmission to occur. See page 4-8 for further guidelines for
setting this parameter.
DCD Wait Delay
(1) 1 Only used with Half-Duplex without Continuous Carrier Control Line
setting. Defines how long, in seconds, the processor will wait for
DCD to go low so that it can transmit, before giving up and erroring
out MSG.
Pre-Transmit Delay 0 Defines the amount of time, in 1 millisecond increments, that elapses
between when the processor has a message to send and when it
asserts the RTS signal (if handshaking is selected) or begins
transmitting (if no handshaking is selected).
(1) OS Series C, FRN 7and higher.
Table 4.7 Define these communication parameters when configuring an SLC 5/03, 5/04, or 5/05 processor for DF1 Radio Modem
communication.
Tab Parameter Default Selections