On 2006-08-03 06:07:31, H J van Rooyen wrote: > Thanks - will check it out - seems a lot of money for 555 functionality > though.... > > Especially if like I, you have to pay for it with Rand - I have started > to call the local currency Runt...
Depending on what you're up to, you can make such a thing yourself relatively easily. There are various possibilities, both for the reset/restart part and for the kick-the-watchdog part. Since you're talking about a "555" you know at least /some/ electronics :) Two 555s (or similar): - One wired as a retriggerable monostable and hooked up to a control line of a serial port. It needs to be triggered regularly in order to not trigger the second timer. - The other wired as a monostable and hooked up to a relay that gets activated for a certain time when it gets triggered. That relay controls the computer power line (if you want to stay outside the case) or the reset switch (if you want to build it into your computer). I don't do such things with 555s... I'm more a digital guy. There are many options to do that, and all a lot cheaper than those boards, if you have more time than money :) Gerhard -- http://mail.python.org/mailman/listinfo/python-list