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I was just wondering what functions/API's I should be looking at to a) retrieve the current time on the systems clock (preferably in an integer) and b) what functions and such are used to interact with the COM ports on a windows machine.
any help appreciated.
while I'm at it, quick question, how do you make a pointer to a boolean array a parameter for a function and then how do you call it?
The system time.... It's just gonna work in Visual C++ with MFC, because the GetLocalTime function is in MFC. There are of course som api function that will do the job, but I don't remember which those are... Anyway...
//get the system time like this
SYSTEMTIME *pSysTime = new SYSTEMTIME();
GetLocalTime(pSysTime);
//and then access the SYSTEMTIME like this
int day = pSysTime->wDay
int month = pSysTime->wMonth
Boolean array question:
void mymethod(bool* par)
{
bool newpar = *par;
}
main()
{
bool var;
mymethod(&var);
}
Hope this helps :)
As far as accessing serial ports is concerned...
The "correct" Win32 way of doing this, as far as I know, is with CreateFile() on "com1" etc.
Here is some code I wrote a while ago...
Ok, that opens the com port, but what about setting speed, etc? You want to be able to do this.Code:static HANDLE hCom;
void vecserial_init()
{
char *pcCommPort = "COM1";
DCB dcb;
BOOL fSuccess;
hCom = CreateFile( pcCommPort,
GENERIC_READ | GENERIC_WRITE,
0, // must be opened with exclusive-access
NULL, // no security attributes
OPEN_EXISTING, // must use OPEN_EXISTING
0, // not overlapped I/O
NULL // hTemplate must be NULL for comm devices
);
// TODO: check open succeeded
My actual code is available upon request, but essentially the same but with more error handling.Code:fSuccess = GetCommState(hCom, &dcb); // TODO: check fSuccess
// Fill in DCB: 38400 bps, 8 data bits, no parity, and 1 stop bit.
dcb.BaudRate = CBR_38400; // set the baud rate
dcb.ByteSize = 8; // data size, xmit, and rcv
dcb.Parity = NOPARITY; // no parity bit
dcb.StopBits = ONESTOPBIT; // one stop bit
fSuccess = SetCommState(hCom, &dcb); // TODO: checkfSuccess
To read/write the serial port, you can then use ReadFile and WriteFile respectively (read M$ doc for more info)
Slarty
hmm, that makes it look like I'm going to have to write my own device drivers to do what I want to do.
you see I'm trying to write a program to control a little LED panel that I'm going to make up.
Noone happens to have any links or tutorials they think I might find useful do they?
What is it that you want to do? Writing device drivers is not desireable.Quote:
hmm, that makes it look like I'm going to have to write my own device drivers to do what I want to do.
AFAIK, you can do most things with the serial port without writing any weird drivers. There are more serial port functions, I just described the ones I thought you were likely to use.
Slarty
I want to be able to switch on and off individual LED's on the panel. I'm also unsure as to what sort of IC's I would need for the panel..Quote:
Originally posted here by Fabs
you see I'm trying to write a program to control a little LED panel that I'm going to make up.
You probly need a serial to parallel converter IC, and use the output bits to switch on/off the individual LED. Do a search on "serial to parallel". Or you may even try to control them via paralel (LPT) port...
Peace always,
<jdenny>
so why so I need to convert from serial to parallel? I don't know a whole lot about how com ports and such work.
Writting apps to controll ( simple hardware ) via a parallel port is realy easy..
the parallel port can easily be used fo 16bit output to your hardware..
Then we're talking about a LOT of readings... Why don't u search "serial communication" at google?Quote:
so why so I need to convert from serial to parallel? I don't know a whole lot about how com ports and such work.
As the_Jinx suggested, u may want to try the parallel port solution, although afaik it's 8 bit, not 16 bit.
Peace always,
<jdenny>
well how incredibly useful.
Got any texts or something that could help me in any way?
yup you were right Jdenny ( I just opened my box of old projects and found me some good old hardcopy documentation.. )
If you'd like I could help you with the layout although this http://www.computerhope.com/help/parallel.htm should help you out a bit :)
General info on parallel ports: http://www.doc.ic.ac.uk/~ih/doc/par/
Ok assuming u have no problems with the electronics side, have a look at this project.
http://www.xs4all.nl/~sebdehne/pp_powerSwitch/
It controls (AC) power relays and has a sample shematics diagram. Controlling LEDs should be easier...
U may also consider the DriverLINX Port I/O Driver to get ur 32-bit apps (in any language that can call a DLL) direct access to the I/O ports over the range 0100H to FFFFH.
http://www.doc.ic.ac.uk/~ih/doc/par/port95nt/readme.txt
Peace always,
<jdenny>
mm, I'm pretty sure this is out of my league.
oh well, back to MFC I guess *shrug*