>Yes, ADB is a serial protocol. But the power key is the only key in ADB >keyboards to have a wire of its own. The ADB bus has four lines: +5 V, ground, >data and reset. The fourth line is where the "power" key is connected. It's >inherited from the origins of the ADB bus, first used in the Apple IIgs >series. There, it was used as a Reset key, much in the same way as the >Macintosh's Programmers Switch. If the reset line on the ADB bus was connected >to ground, the machine rebooted. Later, when ADB was adopted by the Macintosh >in the Mac SE and Mac II models, the reset key was redefinded as a power key. >
Correct. Later Macintoshes (IIsi and newer) also used the same programmer's switch feature that was used on the IIgs... Essentually you hit command-control-power to reboot the machine. Some of the newer Macs (read most of the Quadras with programmer's switches on the CPU) still operated in the old manner, where the command-control-power function does not work... >BTW: I'm almost sure than in the original ADB keyboard released with the IIgs >(the "borderless" one), you had to press the Control key in addition to the >Reset key in order to it to work (it was the way the Reset key worked in all >Apple II models except for the original Apple II from 1977). This was made to >reduce the chance of resetting the machine accidentally and, of course, was >changed in later Macintosh keyboards. > Yes, if you want to stop the machine from booting, you hit control-reset. To do a self-test, you hold down both command and option at the same time as hitting control and reset. Some II+'s can be configured to use only the reset key as a break key, in which case, control and reset will reboot the machine. >Greetings, > >Antonio Rodríguez (Grijan) ><ftp://grijan.cjb.net:21000/> > > -J -- Compact Macs is sponsored by <http://lowendmac.com/>. Support Low End Mac <http://lowendmac.com/lists/support.html> Compact Macs list info: <http://lowendmac.com/lists/compact.shtml> --> AOL users, remove "mailto:"; Send list messages to: <mailto:compact.macs@mail.maclaunch.com> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive:<http://www.mail-archive.com/compact.macs%40mail.maclaunch.com/> --------------------------------------------------------------- iPod Accessories for Less at 1-800-iPOD.COM Fast Delivery, Low Price, Good Deal www.1800ipod.com ---------------------------------------------------------------
