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vacpress
- 23rd January 2007, 05:52
Hey,

I have been experimenting with usb and the values of the various capacitors to see what it does to reliability. So far, it dosent seem to have much effect, in fact the app seems to run fine with pin 18 on my 4550(vusb) left hanging.


comments?

thanks. just trying to understand as much as possible!

Darrel Taylor
- 25th January 2007, 02:58
Still using the same proto-board
http://www.picbasic.co.uk/forum/showthread.php?p=31405
So I'm sure that has a big affect on everything.

Here's the results I got.
Error window Recognized RX Data
------------ ------------ ----------
No Cap YES Never n/a
20pf YES Never n/a
40pf Intermittant Occasionaly NO Data
100pf NO YES NO Data
220pf NO YES Sometimes
440pf NO YES Almost Always
.001uf NO YES Always
.01uf NO YES Always


In this case, anything below .001uf either doesn't work or is unreliable.
But I'm still sticking with .22uF

.

vacpress
- 25th January 2007, 05:03
yeah.. in this case it worked with none, but ive got it going through a 1uf now, as that was convenient. I will take photos in a bit and paste em up..

right now it is still reading lots of stuff about usb and hid... sort of a bundle