Delphi under xp system how to print port LPT1 according to binary 0 x36, 0 x39, 0 x3c; It is best to give a code

CodePudding user response:

Myself,,

CodePudding user response:

 const 
LptData: an array of Char=[0.. 2] (# $36 # $39, # $3 c); 

Procedure lptProcess (); 
Var 
HFile: Cardinal; 
ByteWrited: Cardinal; 
Overlapped: TOverlapped; 
The begin 
HFile:=CreateFile (' LPT1: 'GENERIC_WRITE FILE_SHARE_WRITE, nil, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0). 
If hFile=INVALID_HANDLE_VALUE then 
The Exit; 

Overlapped. HEvent:=CreateEvent (nil, False, False, nil); 

While True do 
The begin 
If not WriteFile (hFile, lptData, length (lptData), byteWrited, @ Overlapped) then 
Case WaitForSingleObject (Overlapped. HEvent, 4000) of 
WAIT_OBJECT_0:; 
WAIT_TIMEOUT WAIT_ABANDONED: 
The begin 
Break; 
The end; 
The end; 
The end; 


The CloseHandle (hFile); 
The CloseHandle (Overlapped. HEvent); 

The end; 

CodePudding user response:

Do you have any simple some writing, Pal? I am a rookie, amateur saw half a day, didn't know how to put my thoughts with your statement,
I want to do what is on the parallel port output eight independent square-wave waveform (used to parallel program should be set different number), but the specific what time change the waveform with my sleep (x) to control the output of a waveform after me to calculate the value of x, then output the next, the time interval may be a few hundred milliseconds, may also have a few milliseconds,