Can't you use DMA or similar to send a pulsetrain to a port at a specified speed? I recall something about this from my old soundblaster playback days using dual buffers etc... That was dos, but I still wonder. KreAture ----- Original Message ----- From: "Herbert Graf" To: Sent: Wednesday, January 22, 2003 11:53 PM Subject: Re: [ot]: oscilloscope pulse display > >>I have checked the pulse, on the parallel port of an older PC > running win98, using a CNC program, > > and the thing puts out a very nice 5volt square wave, it glitches once > in a while, I guess this is the noise spoken about, but it is doable to > do this in windows, or was.... > > then checking my simple program again using a delay, it was no > better, it seems that if you remove everything except the statement > which turns on the pin, it will change it from 0 to 5vdc, but something > turns the pin off again automatically, some windows feature or function. > > So, like somebody said, it's back to the API or write another dll or > what ever, > > If any of you know the solution to controling pins on the parallel port, > your help is appreciated.... << > > > > Which version of windows are you using? For any version of Win9x (including > Me) I haven't had any problems with manipulating the ports manually (I use > inline assembler to do it). For WinNT (including XP and 2K) you need a > driver to allow direct access to the port. Harder, slower, but doable. You > could always write your own driver if you really needed the speed, but > that's in the realm of "crazy talk" IMHO (writing drivers for windows is NOT > fun). TTYL > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads