INKEY - Revision history

Admin: Created page with "= Action = Returns the ASCII value of the first character in the serial input buffer.
2013-02-11T19:20:07Z

Created page with "= <span class="f_Header">Action</span> = Returns the ASCII value of the first character in the serial input buffer. <span style="font-family: Arial;"> </span> <span st..."

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= <span class="f_Header">Action</span> =

Returns the ASCII value of the first character in the serial input buffer.

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= <span class="f_Header">Syntax</span> =

var = <span class="f_Syntax">INKEY</span>()

var = <span class="f_Syntax">INKEY</span>(#channel)

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= <span class="f_Header">Remarks</span> =
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{| width="488" cellspacing="0" cellpadding="1" border="1" style="border: 2px solid rgb(0, 0, 0); border-spacing: 0px; border-collapse: collapse;"
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Var

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Byte, Integer, Word, Long or String variable.

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Channel

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A constant number that identifies the opened channel if software UART mode

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If there is no character waiting, a zero will be returned.

Use the IsCharWaiting() function to check if there is a byte waiting.

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The INKEY routine can be used when you have a RS-232 interface on your uP.

The RS-232 interface can be connected to a comport of your computer.

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As zero(0) will be returned when no character is waiting, the usage is limited when the value of 0 is used in the serial transmission. You can not make a difference between a byte with the value 0 and the case where no data is available.

In that case you can use IsCharwaiting to deterimine if there is a byte waiting.

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= <span class="f_Header">See also</span> =

[[WAITKEY]] , [[ISCHARWAITING]]

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= <span class="f_Header">Example</span> =

<br/><source lang="bascomavr">
'-----------------------------------------------------------------------------------------
'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
</source><br/>{{Languages}}

[[Category:BASCOM Language Reference]]