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Inpfunction
Returns a value at a hardware port.
Syntax
Declare Function Inp ( ByVal port As UShort ) As Long
Parameters
| Name | Description | |
|---|---|---|
port | Port number to read. |
Return value
The value at the specified port.
Description
This function retrieves the value at 'port' and returns immediately.
Remarks
Usage
value = Inp(port)
Platform Differences
- In the Windows and Linux versions three port numbers (&H3C7, &H3C8, &H3C9) are hooked by the graphics library when a graphics mode is in use to emulate QB's VGA palette handling. This use is deprecated; use
Paletteto retrieve and set palette colors.
- Using true port access in the Windows version requires the program to install a device driver for the present session. For that reason, Windows executables using hardware port access should be run with administrator permits each time the computer is restarted. Further runs don't require admin rights as they just use the already installed driver. The driver is only 3K in size and is embedded in the executable.
See also
Example
'' Turn off PC speaker
Out &h61,Inp(&h61) And &hfc
Reference
- Documented in KeyPgInp.html