On Mon, 2008-04-28 at 21:47 -0400, Kenneth Lerman wrote: > Does anyone use a single chip solution consisting of a single 8 pin > microprocessor? > > An Atmel atTiny13 is $1.40 in an 8 pin dip package. These chips power up > nicely, require no external oscillator, and are easy to program. If you > don't trust them, get two. Use one to drive the high side of the SSR relay > and the other to drive the low side. The paranoid among us can take the > drive signals from the chips and feed them back as inputs to the main > processor. It would then check that the chips are in the no signal state > prior to starting the charge pump. > > It wouldn't do to have a failure of the failsafe circuit be undetected. > > Ken
Who's checking the failsafe circuit checker? If you can do the programming easily, these eight pin processors certainly are cheap. I find it a little frustrating to consider using them because I always try to think of other functions I can put in while I am there. I am the only one here, so no one shoots the engineer to finish the project. -- Kirk Wallace (California, USA http://www.wallacecompany.com/machine_shop/ Hardinge HNC/EMC CNC lathe, Bridgeport mill conversion, doing XY now, Zubal lathe conversion pending Craftsman AA 109 restoration Shizuoka ST-N/EMC CNC) ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
