LED intensity control by rs232

Hi
I looking for LED intenstity control through rs232 and better I can program by Visual basic any idea?

Thank you

Sidney

you could use the parallel port (5V logic) and create a PWM (pulse wave modulation - a constant frequency with altering ON and OFF times) to control the LED's intensity

Heres a DLL that helps control the parallel port

**broken link removed**


Read the file "Brief Run Down(a net copy & paste).doc"

Fred Bulback created it, all credit goes to him

any chance I can use rs232 to control or only parallel port only?
thank you

gramo said:

you could use the parallel port (5V logic) and create a PWM (pulse wave modulation - a constant frequency with altering ON and OFF times) to control the LED's intensity

Click to expand...

It would be easier to pulse a data pin on the parallel port if you have a parallel port. Use pulse width modultaion to drive it.

You can use RS232 and turn off all the signals and use that. But parallel would be less work. With RS232, you might have to loop some signals back, like RTS/CTS, etc.

Google for serial port programming and read up on the signals. I think there are two set you might have to deal with and you can tie a pair to DTR if I recall.