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geekhack Projects => Making Stuff Together! => Topic started by: margo baggins on Sun, 27 April 2014, 06:18:20

Title: have I broken this matrix
Post by: margo baggins on Sun, 27 April 2014, 06:18:20
I started soldering this up last night, but I realised this morning I don't think I have soldered the diodes correctly, I have accidentally soldered before each switch diode - here is pic:

(http://i13.photobucket.com/albums/a258/lymph/IMG_2790_zpsaca88514.jpg) (http://s13.photobucket.com/user/lymph/media/IMG_2790_zpsaca88514.jpg.html)

Do I need to take this apart and start it again?
Title: Re: have I broken this matrix
Post by: OldDataHands on Sun, 27 April 2014, 13:00:01
Yes.
Title: Re: have I broken this matrix
Post by: margo baggins on Sun, 27 April 2014, 16:46:55
Yes.

I'd figured as much :P

That's what happens doing stuff when tired, I looked at it this morning and just thought, bahhh that's all wrong! thanks :)
Title: Re: have I broken this matrix
Post by: jacobolus on Mon, 28 April 2014, 00:39:24
The usual way to do things is to have the diode between the switch and the column/row. But I知 not 100% convinced that your way won稚 work. You値l be routing the current through a bunch more diodes than necessary, but I think they might still serve to isolate switches so you avoid ghosting.
Title: Re: have I broken this matrix
Post by: margo baggins on Mon, 28 April 2014, 02:57:29
The usual way to do things is to have the diode between the switch and the column/row. But I知 not 100% convinced that your way won稚 work. You値l be routing the current through a bunch more diodes than necessary, but I think they might still serve to isolate switches so you avoid ghosting.

It's no bother - only took me an hour and a bit to do that bit - won't take me long to take it all off and start again, I have thousands of diodes so that's no thing! Will start it again sometime this week.
Title: Re: have I broken this matrix
Post by: OldDataHands on Mon, 28 April 2014, 09:16:05
The usual way to do things is to have the diode between the switch and the column/row. But I知 not 100% convinced that your way won稚 work. You値l be routing the current through a bunch more diodes than necessary, but I think they might still serve to isolate switches so you avoid ghosting.
The voltage dropped across each diode renders this circuit useless...
Title: Re: have I broken this matrix
Post by: jacobolus on Tue, 29 April 2014, 05:34:15
Oh, right. :-) If the voltage drops half a volt or something for each diode, then 10 in a row is definitely not going to work out. :-) Re-wire away!