Olin, I did a quick search on the net for "Brensenhams Algorithm" and quickly found several explanations of this Computer Graphics method for selecting which pixel should be illuminated when drawing a line on-screen. It fits nicely with my objective, it's simply a matter of replacing the X displacement by the number of processor cycles and the Y displacement by the difference between the target and the original values =) I also found an Integer version of the algorithm which I think can be adapted quite easily to PIC assembly. =)) For those interested, here is one of the best documents I've found : http://graphics.cs.ucdavis.edu/GraphicsNotes/Bresenhams-Algorithm/Bresenhams -Algorithm.html Have you worked in computer graphics before or is this algorithm considered common knowledge ? Anyway, many thanks! Tobie Horswill Le Projet Ex Machina, QC. CAN. thorswil@exmachina.qc.ca ----- Original Message ----- From: "Olin Lathrop" To: Sent: Saturday, October 13, 2001 3:16 PM Subject: Re: [EE]: Multiple values accelerating at different rates over the same time > > Since I don't need such a high resolution (1 cycle) and couldn't possibly > > calculate all these values fast enough (with a PIC)I could simplfy these > > operations by updating the values only every 20,000 cycles (50 Hz refresh > > rate with a 20MHz clock) his still gives some rather hefty fractional > values > > to handle with a PIC. Besides, this method requires twice the amount of > > memory to store the Rate constants ... > > > > Any thoughts ? > > How about a Bresenham algorithm? > > > ******************************************************************** > Olin Lathrop, embedded systems consultant in Littleton Massachusetts > (978) 742-9014, olin@embedinc.com, http://www.embedinc.com > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads