WAITKEY

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Contents

Action

Wait until a character is received.

 

 

Syntax

var = WAITKEY()

var = WAITKEY(#channel)

 

 

Remarks

var

Variable that receives the ASCII value of the serial buffer.

 

Can be a numeric variable or a string variable.

#channel

The channel used for the software UART.

 

While Inkey() returns a character from the serial buffer too, INKEY() continues when there is no character. Waitkey() waits until there is a character received. This blocks your program.

 

 

See also

INKEY , ISCHARWAITING

 

 

Example


'-----------------------------------------------------------------------------------------
'name : inkey.bas
'copyright : (c) 1995-2005, MCS Electronics
'purpose : demo: INKEY , WAITKEY
'micro : Mega48
'suited for demo : yes
'commercial addon needed : no
'-----------------------------------------------------------------------------------------
 
$regfile = "m48def.dat" ' specify the used micro
$crystal = 4000000 ' used crystal frequency
$baud = 19200 ' use baud rate
$hwstack = 32 ' default use 32 for the hardware stack
$swstack = 10 ' default use 10 for the SW stack
$framesize = 40 ' default use 40 for the frame space
 
Dim A As Byte , S As String * 2
Do
 A = Inkey() 'get ascii value from serial port
's = Inkey()
If A > 0 Then 'we got something
 Print "ASCII code " ; A ; " from serial"
End If
Loop Until A = 27 'until ESC is pressed
 
A = Waitkey() 'wait for a key
's = waitkey()
Print Chr(a)
 
'wait until ESC is pressed
Do
Loop Until Inkey() = 27
 
'When you need to receive binary data and the bibary value 0 ,
'you can use the IScharwaiting() function.
'This will return 1 when there is a char waiting and 0 if there is no char waiting.
'You can get the char with inkey or waitkey then.
End

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