An example dialog is shown below:
The data presented on the dialog box is explained below:
COM Port Number This dropdown listbox allows you to specify the COM name of the selected stallion serial communications port. The allowable COM names are listed. The currently configured name is postpended with '(current)' (as shown in the example above). COM names that are used by other ports are postpended with '(is used)', unused/available COM names have only the COM name listed.
Always Assert DCD High This checkbox modifies the behavior of the DCD control line to a configuration whereby the DCD line will always be reported as asserted. This is a useful way to avoid the usual open actions of waiting for carrier to be asserted.
Always Assert DSR High This checkbox modifies the behavior of the DSR control line to a configuration whereby the DSR line will always be reported as asserted.
Enable DTR Follow This checkbox modifies the behavior of the DTR control line to force it to follow data transmission. This means the DTR control line is asserted whenever data is transmitted, and is not asserted whenever data is not being transmitted. This option is most useful in RS-485/RS-422 communications, particularly as on Dual Interface EasyConnection panels the DTR line tri-states the transmitter for multi-drop operation.
Enable RTS Follow This checkbox modifies the behavior of the RTS control line to force it to follow data transmission. This means the RTS control line is asserted whenever data is transmitted, and is not asserted whenever data is not being transmitted. This option is most useful for RS-485/RS-422 communications, where a Stallion RS-232 port is connected to an RS-232 to RS-485 converter, or to a half-duplex radio modem.
Hold Writes Until Tx Complete This checkbox modifies the behavior of the writes to the Stallion serial communications port. The driver will not complete writes until the data is in the hardware buffers of the UART. This option removes driver write optimizations (and decreases the data throughput possible). It may though may be useful for applications where more control over the timing of transmitted data is desired or when using the EV_TXEMPTY event mask is not desired.
Lock RTS Hw Flow Control This option when activated, locks the port into a state where it is continuously using the RTS hardware control line (this is the flow control of the receiver).
Lock CTS Hw Flow Control This option when activated, locks the port into a state where it is continuously using the CTS hardware control line (this is the flow control of the transmitter).
Ignore Echo (RS-485 Only) This option is only available on RS-485 ports and controls the echo characteristics of half-duplex RS-485 communications. Checking the box configures the driver to ignore any data received while it is transmitting. In other words, the option disables the port receiver whenever data is being transmitted. This option is useful when an application is utilizing an EasyConnection RS-485 port and does not expect to receive its own transmissions.
Rx FIFO Threshold This dropdown listbox controls the way that the UART hardware buffers are utilized on reads. 'Automatic' indicates that the decisions on data buffering should be made by the driver (this results in optimization for maximum throughput). The additional 'x bytes' choices indicate the number of bytes the hardware Rx FIFO in the UART should buffer before informing the driver that data has been received. The number of bytes available for buffering depends upon the UART being used.
Tx Draining Timeout This option allows you to specify the transmit draining timeout. This is the number of milliseconds that the port is left open after an application has closed the port if untransmitted (buffered) data exists. This option is useful for correcting applications which assume that a write completion indicates all the data has been sent and then immediately closes the port.
Find Devices Attached to Port This dropdown listbox controls the way that devices which are attached to the port are detected. This option controls the layered serial enumeration driver (serenum.sys) by indicating how often the serial enumerator should check the port for attached devices.
OK button This button enables any changes made and closes the dialog box.
Cancel button This button ignores any changes made and closes the dialog box.
Defaults button This button restores the factory default settings for the port.
Help button This button displays the help
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