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Re: Caps a poppin!
- Subject: Re: Caps a poppin!
- From: "David Wilson" <mcs6502@gmail.com>
- Date: 6 Jan 2007 18:12:04 -0800
- Complaints-to: groups-abuse@google.com
- Injection-info: 51g2000cwl.googlegroups.com; posting-host=220.233.163.88; posting-account=v7oSuQ0AAAAZLwd761jftD5qph4UbWwl
- Newsgroups: comp.sys.apple2
- Organization: http://groups.google.com
- References: <459f7c41$0$38156$c30e37c6@lon-reader.news.telstra.net> <1168096416.385492.162300@s34g2000cwa.googlegroups.com> <45a04fff$0$38159$c30e37c6@lon-reader.news.telstra.net>
- User-agent: G2/1.0
- Xref: g2news2.google.com comp.sys.apple2:15955
Tristan Mumford wrote:
> Sidenote. Is the card slot at J12, ie the 8th slot labelled "USER1"? or is
> it referring to something else. It caught my curiosity.
USER1 is pin 39 of the Apple ][(+) bus. It was replaced by the 6502
SYNC signal on the IIe.
If the USER1 jumper is connected then any card can pull pin 39 low and
disable all on-board decoding of $C000..C7FF.