Thanks for the reply Wade. > My guess would be that you can't overclock the -04 to 20MHz. It should > I kinda figured...was just trying to save some money on buying a new part when I have some -04s already. Breadboarding is not really an issue here - Just make sure you're using a > crystal as the RC oscillator will not run that fast. I plan on using a metal can oscillator...the 4 pin DIP kind. Do I have to worry about capacitance on the breadboard or anything? > As for the 250kbps, i'd say no way. Simply speaking, you have 4MHz so > that's 1 MIPS, so that gives you 4 instructions per data, right?! 2 > instructions cycles / branch instruction (maybe only 1 to go to the isr, but > i guess 1 to save states, 1 to restore states and 1 to retfie) so you're > already done without having processed anything! Well, in theory, but I believe it's kilo-BITs per second, so I'd have more time. Am I right? > If you want 20MHz, I'd say you'd have to buy the 20MHz chip. Even then > you'll be in for some trouble. It seems like a scenix communications > controller running 50MIPS may more be what you're looking for? The price is > quite similar, I guess it depends on your application! Well, my application isn't too processor intensive, so I should be fine. In fact, I know that even more is being done on a PIC at 16Mhz. I was just wondering if I could do it in even less, and then save on the parts costs. > ----- Original Message ----- > From: "Josh Koffman" > > Hi all. I know there have been discussions about overclocking the > > f84-04, but has anyone overclocked the f87x? Specifically the 16f877-04? > > I want to take it up to 20Mhz, and I'm wondering if it will work. Also, > > at those speeds, will I run into problems if I try to breadboard? Now my > > final question, can I receive a 250kps data stream using the UART if my > > clock is at 4Mhz? Will the buffer overflow if I'm not exceedingly quick > > in my processing of the data? I also don't want to spend 90% of my time > > in the ISR actually receiving the data. -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics