Serialinchk(); Serialinrecord(); Serialflush(); Operation - Campbell SDM-SI01A Product Manual

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6.3.1.7 SerialInChk()

This returns the number of characters that have been received by the SDM-SIO1A and that are

currently held in its buffer (0-6143).

No special information.

This instruction will purge all information in the data logger and SDM-SIO1A transmit and receive

buffers.

This section includes more detail on less common modes of operation, provides details on how

to save power use, and shows the internal configuration of the SDM-SIO1A when configured in

RS-485 or RS-422 full-duplex mode.

7.1 Configuring handshaking and receive-

only modes

Handshaking is a method used by RS-232 to ensure communications equipment is free to

receive or transmit data. This interface is often called RTS/CTS (hardware handshaking) or

DTR/DTE.

Automatic handshaking for the SDM-SIO1A is activated through use of the BaudRate

parameter of the

SerialOpen()

instruction.. When the BaudRate value is set to a negative

number, the SDM-SIO1A will enable automatic handshaking. It is worth noting that normally

setting the BaudRate to a negative number will enable automatic baud rate detection; this is

not the case for the SDM-SIO1A.

When enabled, the two I/O ports (pins 8 and 11) will operate as RTS and CTS lines. It is important

that the remote equipment supports handshaking as no data will be sent if handshaking is

enabled but is not supported by the equipment the SDM-SIO1A is connected to.

Once handshaking is enabled, pins 8 and 11 are no longer available for general use and are

dedicated to the auto-handshaking system.

SDM-SIO1A and SDM-SIO4A Serial Input/Output Modules

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Sdm-si04a