Lantronix Hub manual Flow Control, Modems and Modem Signaling

MSS User Guide 4: Configuration

Flow Control

Note: RTS/CTS Flow Control is not available in RS-485 mode.

Both RTS/CTS (hardware) and XON/XOFF (software) flow control methods can be used on the MSS. RTS/CTS controls data flow by sending serial port signals between two connected devices. XON/XOFF controls data flow by sending particular characters through the data stream: Ctrl-Qto accept data (XON) and Ctrl-Swhen data cannot be accepted (XOFF).

Note: Applications that use Ctrl-Q and Ctrl-S will conflict with XON/XOFF flow control, in which case RTS/CTS is recommended.

To switch between flow control methods, use the Change Port Flow Control command followed by the preferred method. If you do not wish to use flow control at all, specify None.

Figure 4-48: Enabling Recommended Flow Control for MSS-VIA and MSS4

Local>> CHANGE PORT 1 FLOW CONTROL CTSRTS

Figure 4-49: Enabling Recommended Flow Control for MSS100

Local>> CHANGE FLOW CONTROL CTSRTS

or

Local>> CHANGE FLOW CONTROL XON

If you're using XON/XOFF flow control, the XON/XOFF characters will be removed from the data stream by default. To prevent this removal, the Passflow option can be enabled. However, passflow is unnecessary in most situations. See the Commands chapter in the MSS Reference Manual for more information.

Figure 4-50: Enabling Passflow for MSS-VIA and MSS4

Local>> CHANGE PORT 1 PASSFLOW ENABLE

Figure 4-51: Enabling Passflow for MSS100

Local>> CHANGE PASSFLOW ENABLE

Modems and Modem Signaling

The following sections explain some of the MSS options that are typically considered to be modem-related. They do not apply exclusively to modems, but to communications devices in general. Most options are mutually exclusive when enabled.

Note: Modem Emulation Mode, in which the MSS acts like a modem and only accepts AT modem commands, is discussed in 5:Using the MSS.

After configuring modem-related settings, refer to the Modem Configuration Checklist in 5:Using the MSS.

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