SerialFlush (Clear Characters in Serial Input Buffer)

The SerialFlush function is used to clear any characters in the serial input buffer.

Syntax

SerialFlush ( ComPort )

In the following example, serial data that is received over the datalogger's RS232 port is stored into a string. After 20 characters are received, the remaining serial buffer is cleared using the SerialFlush instruction. SerialInChk is used to monitor the number of characters received.

Public InString As String * 25

DataTable (SerialT,True,-1)
  Sample (1,InString,String)
EndTable

BeginProg
  Scan (5,Sec,3,0)
    SerialOpen (ComRS232,115200,0,0,10000)
    If SerialInChk(ComRS232) > 20 Then SerialFlush (ComRS232)
    SerialIn (InString,ComRS232,100,0,20)
    CallTable (SerialT)
  NextScan
EndProg

Remarks

This function clears the buffer and leaves the port open. If the input buffer should be cleared before each execution of SerialIn, place SerialFlush in the code before the SerialIn instruction.

 

Parameter

ComPort (Communication Port)

The communication port that will be used by the instruction. Note that beginning with OS 6.0, control ports C1 and C2 can be configured individually for transmit (Tx) or receive (Rx). Right-click to display a list.

Alphanumeric Description
ComUSB USB port of the datalogger
ComRS232 RS232 port of the datalogger
Com1 Datalogger's control ports 1 (TX) & 2 (RX)
ComC1_Tx Configures control port 1 for transmit only
ComC1_Rx Configures control port 1 for receive only
ComC2_Tx Configures control port 2 for transmit only
ComC2_Rx Configures control port 2 for receive only
ComRF Integrated RF communication

Type: Constant. For all instructions except SerialOpen, this parameter can also be a variable.