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Path: utzoo!watmath!clyde!cbosgd!cbdkc1!desoto!packard!topaz!@RUTGERS.ARPA:prindle@nadc
From: @RUTGERS.ARPA:prindle@nadc
Newsgroups: net.micro.cbm
Subject: Reset switches
Message-ID: <1029@topaz.ARPA>
Date: Fri, 22-Mar-85 09:37:35 EST
Article-I.D.: topaz.1029
Posted: Fri Mar 22 09:37:35 1985
Date-Received: Sat, 23-Mar-85 04:17:31 EST
Sender: daemon@topaz.ARPA
Organization: Rutgers Univ., New Brunswick, N.J.
Lines: 19

From: prindle@NADC

I realize that the proposed modification to a C64 to add a reset switch
represents the optimal electrical approach.  However, the output of U8 is
the RESET line proper and appears on the expansion connector, the user
port, and the serial bus connector.  By simply grounding this line externally
(with a switch connected to one of those reset lines coming out and ground),
you get a reset effect.  Sure you're shorting the output of U8, a hefty
7406, and sure, it draws a bit of current, but this is no problem as long as
you don't sit on the switch for more than a fraction of a second (wired or's
have been shorting out 7400 gates for ages).  My 64 is 2 years old (a bit
of a record for 64s) and going strong and I use such a reset button daily.
And it doesn't even void your warranty, so if it does break your 64, just
turn it in for a new one.  Most commercially available reset buttons just
hook to one of the external connectors also, although the more sophistocated
ones probably drive the reset line low with a one-shot so it can't be held
low indefinitely.
Frank Prindle
Prindle@NADC.arpa