User`s manual

Using Control Pins

8-59

fclose([s1 s2])

delete([s1 s2])

clear s1 s2

Controlling the Flow of Data: Handshaking

Data flow control or handshaking is a method used for communicating between

a DCE and a DTE to prevent data loss during transmission. For example,

suppose your computer can receive only a limited amount of data before it must

be processed. As this limit is reached, a handshaking signal is transmitted to

the DCE to stop sending data. When the computer can accept more data,

another handshaking signal is transmitted to the DCE to resume sending data.

If supported by your device, you can control data flow using one of these

methods:

•Hardware handshaking

•Software handshaking

Note Although you may be able to configure your device for both hardware

handshaking and software handshaking at the same time, MATLAB does not

support this behavior.

You can specify the data flow control method with the

FlowControl property.

FlowControl is hardware, then hardware handshaking is used to control

data flow. If

FlowControl is software, then software handshaking is used to

control data flow. If

FlowControl is none, then no handshaking is used.

Hardware Handshaking

Hardware handshaking uses specific serial port pins to control data flow. In

most cases, these are the RTS and CTS pins. Hardware handshaking using

these pins is described in “The RTS and CTS Pins” on page 8-10.

FlowControl is hardware, then the RTS and CTS pins are automatically

managed by the DTE and DCE. You can return the CTS pin value with the

PinStatus property. You can configure or return the RTS pin value with the

RequestToSend property.