I need an experienced reply! (LPT -SPP strobe pin!)

[1202]

Ok

I wish to use the strobe pin of the LPT if possible

1.) The strobe pin is hardware controlled on SPP right?

2.) Is this ruffly the correct order of things:-

a. Date lines get data on them for 500NS
b. Then strobe pin goes from high to low for 1uS
c. Then the strobe pin goes from low to high again after 1 us
d. Then data is still present on the line for another 500NS ruffly??

help?? is this about right, I have found info on the Standard Parallel Port but I wanted to confirm info on the strobe pin, I'll have to have a play around myself but I just thought of asking first.

I want to use the strobe pin to clock an IC!

thanks

[1202]

I found this site somewhere where its close to what I said but it says the strobe goes from a high to low transition for 500ns .5us and not 1us!

hmm?

http://www.geocities.com/dsaproject/com ... _port.html

that website sounds correct... any thoughts on that, its probably not going to be to criticle when I think about it

[GARTHWILSON]

Your data needs to be valid at least .5us before the strobe pulse begins.
The strobe pulse needs to be at least .5us long.
Your data needs to remain valid at least .5us after the end of the strobe pulse.

These are minimum times. You can go much longer if you're running a slow computer or a language that has a ton of overhead and can't do it this fast. As long as you meet the minimums, you shouldn't have any trouble. Unless your computer is extremely slow though, you'll probably want to use at least the BUSY line as well to avoid overrunning the printer's buffer. I've written such a printer driver on three different occasions and it worked the first time every time.