ThinkClassic

Dnal

Member

Registered: 2015-01-03

Posts: 59

LCII J18???

Does anyone know what J18 on an LCII board was supposed to be?  I had always assumed it was a vestige of the second floppy port on the original LC, but it has 16 pins and not 20?!?

bbraun

Member

Registered: 2014-05-29

Posts: 1,064

Website

Re: LCII J18???

I don't have an LCII to look at, but I'd probably start by seeing what those pins are connected to.

unity

Member

Registered: 2015-01-09

Posts: 82

Re: LCII J18???

My memory may be wrong, but I seem to think it was to do with some video card feature that went unused or something.

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Dnal

Member

Registered: 2015-01-03

Posts: 59

Re: LCII J18???

The pins seam to go everywhere, one goes to the expansion slot a couple into vias but I haven't traced more.  There is also a 6 pin jumper block labeled J17, that looks interesting.

uniserver

Member

From: Sf, Mi

Registered: 2014-05-15

Posts: 956

Website

Re: LCII J18???

yeah its just some left over portholes from the previous LC1 (floppy port) PCB design, it does and means nothing.
this nice ting about that secondary floppy port with the LC1 is that its fully HD20 compatible

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