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== (**COPIED FROM ENGLISH PAGE**) === <span class="f_Header">Action</span> =

Enable timeout on the hardware UART and software UART.

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

<span class="f_Syntax">$TIMEOUT</span>&nbsp;= value

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= <span class="f_Header">Remarks</span> =
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Value

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A constant that fits into a LONG , indicating how much time must be waited before the waiting is terminated.

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All RS-232 serial statements and functions(except INKEY) that use the hardware UART or software UART, will halt the program until a character is received. Only with buffered serial input you can process your main program while the buffer received data on the background.

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[[File:Notice.jpg|left|Notice.jpg]]&nbsp;$TIMEOUT is an alternative for normal serial reception. It is not intended to be used with buffered serial reception.

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When you assign a constant to $TIMEOUT, you actual assign a value to the internal created value named&nbsp;<span style="font-style: italic;">___TIMEOUT</span>.

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This value will be decremented in the routine that waits for serial data. When it reaches zero, it will terminate.

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So the bigger the value, the longer the wait time before the timeout occurs. The timeout is not in seconds or microseconds, it is a relative number. Only the speed of the oscillator has effect on the duration. And the value of the number of course.

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When the time out is reached, a zero/null will be returned to the calling routine. Waitkey() will return 0 when used with a byte. When you use INPUT with a string, the timeout will be set for every character. So when 5 characters are expected, and they arrive just before the timeout value is reached, it may take a long time until the code is executed.

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When the timeout occurs on the first character, it will return much faster.

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When you already sent data, this data will be returned. For example, "123" was sent but a RETURN was never sent, INPUT will return "123". While without the $TIMEOUT, INPUT will not return until a RETURN is received.

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[[File:Notice.jpg|left|Notice.jpg]]When you activate $TIMEOUT, and your micro has two UARTS(Mega128 for example) it will be active for both UART0 and UART1. And for an ATMEGA2560 with 4 UARTS, it will be enabled for all 4 UARTS, but only when no serial input buffer is configured.

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$TIMEOUT is also supported by the software UART. In fact, when you enable it for the hardware UART, you enable it for the software UART as well.

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

[[INPUT]]&nbsp;,&nbsp;[[WAITKEY]]

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

<br/><source lang="bascomavr">
'-----------------------------------------------------------------------------------------
'name : timeout.bas
'copyright : (c) 1995-2005, MCS Electronics
'purpose : demonstration of the $timeout option
'micro : Mega48
'suited for demo : yes
'commercial addon needed : no
'-----------------------------------------------------------------------------------------
 
$regfile = "m48def.dat" ' specify the used micro
$crystal = 8000000 ' 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
 
'most serial communication functions and routines wait until a character
'or end of line is received.
'This blocks execution of your program. SOmething you can change by using buffered input
'There is also another option : using a timeout
'$timeout Does Not Work With Buffered Serial Input
 
 
Dim Sname As String * 10
Dim B As Byte
Do
$timeout = 1000000
Input "Name : " , Sname
Print "Hello " ; Sname
 
$timeout = 5000000
Input "Name : " , Sname
Print "Hello " ; Sname
Loop
 
'you can re-configure $timeout
</source><br/>{{Languages}}

[[Category:BASCOM_Language_Reference/de]]