GUBBINS@RADC-TOPS20.ARPA (Gern) (03/22/85)
Here I go again checking into RESET circuits for other machines I don't have... Several persons and friends have asked me to check into a hardware reset push button for their C64. I have put RESETs on Z-150s and looked into doing it on IBM-PCs. I notice that C64 people, while using their machine have to turn the beast off/on quite a lot. A reset circuit would be much easier, and you would not have the TV/monitor freak with snow. Rumor has it that RESET circuits that plug into one of the C64s ports is available at a price, but this blocks the port or something. Taking a quick look at the C64 schematic in a bookstore last night, The proper way to reset the C64 is to short capacitor C105 to ground which will trigger the 556 timmer to one-shot the RESET(L) line (thru a 7406 open collector inverter). A more nasty way to do it is to grab this RESET(L) (RESET-BAR) at one of the ports and ream it to ground for the time that the 556 would. Has anyone put a reset in their C64? Is it really worth it and the trouble (and the 1/4" hole in the case)??? Thanx, Gern -------
LENOIL@MIT-XX.ARPA (Robert S. Lenoil) (03/22/85)
I've installed a reset key, and yes, I do it the "nasty" way; a pushbutton switch that shorts the reset line to ground. Note that you can get at the reset line from the user port, so if you have a connector, you can just solder on a switch to the connector, plug it in, and presto...reset switch without hole in case. (Reset is also available at the expansion port, but that's a non-standard connector.) Robert Lenoil -------
jrodrig@MITRE-GATEWAY.ARPA (jose rodriguez) (03/22/85)
An outfit called "Public Domain Software" sells a little DIN plug with a switch in the back that connects to the serial bus. The switch just connects two lines together, ground and reset (i think). It has two problems though: resets every device in your serial bus and takes over one of your daisy chain ports. I had trouble when I added a CARDCO +G card (printer interface) because this card had no second DIN connector. (The C64 disk drive has two though). If you can't find their addr in the mags. drop me a line. Jose (soon to change) jrodrig@mitre-gw