PLX30 Series
ASCII Protocol
Ethernet and Serial Gateways
User Manual
ProSoft Technology, Inc.
Page 159 of 200
September 19, 2012
Transmit-Only Mode
A port on the gateway configured to function in transmit-only mode is set up to
only transmit data from the PLX30gateway
’s internal database (received from an
external source) to an ASCII device. When the transmit driver (Tx Driver)
recognizes a new write block containing data (data placed in the gateway
’s
internal database), it transmits this data out to the port. The sequence number
used in the block will be different that that of the previous block, and therefore,
signals that the packet is fully assembled and ready to send. The following
illustration shows data flow for a transmit-only device.
Configuring a Port for Transmit-Only Mode
In order to set a port for Transmit-Only mode, ensure that the
Tx DB Start
parameter in the configuration file contains the starting location of where the data
will be stored. The
Rx DB Start
parameter must contain a value of
-1
. This value
indicates that the port will not receive any data.
