Chris Radek wrote: > On Fri, Apr 25, 2008 at 07:47:32AM -0700, Kirk Wallace wrote: >> I have every thing controlled by parport pins on my Shizuoka which makes >> for an inexpensive conversion, but one of the problems is that if I have >> my main breaker on while booting the EMC2 PC the mill will come up in an >> unsafe state. One of the solutions I was thinking about is, I seem to >> recall a watchdog frequency output from from the estop component that I >> could connect to a watchdog sensor connected to my main power relay. >> >> A quick look did not reveal the information about the estop watchdog. >> Should I keep looking? >> >> Does anyone have a link to a watchdog sensor circuit that would output >> high at the set frequency and low in all other conditions? >> >> Is there a better way to do this? >> > > There is a charge pump component that toggles its output every time > its function is run... >
That HAL component makes the charge pump signal. I think Kirk is looking for the real circuit that uses the charge pump signal to turn on a relay. I built one for my Shoptask, unfortunately I think I just drew the circuit on a piece of paper and don't have it in electronic form. It is on the board described in this blog posting (the board also contains two relays with drivers and three optically isolated digital inputs): http://jmkasunich.com/cgi-bin/blosxom/shoptask/breakout-board-12-19-07.html If I remember when I get home I'll try to draw up a little schematic for a charge pump and post it. Regards, John Kasunich ------------------------------------------------------------------------- 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
