<html><body bgcolor="#FFFFFF"><div>This is truely interesting project :-D</div><div><br></div><div>Can't wait to read the next edition.</div><div><br></div><div>HC</div><div><br>On Nov 24, 2012, at 20:00, <a href="mailto:arm-netbook-request@lists.phcomp.co.uk">arm-netbook-request@lists.phcomp.co.uk</a> wrote:<br><br></div><blockquote type="cite"><span>Message: 2</span><br><span>Date: Sat, 24 Nov 2012 15:18:43 +0000</span><br><span>From: "luke.leighton" <<a href="mailto:luke.leighton@gmail.com" x-apple-data-detectors="true"><a href="mailto:luke.leighton@gmail.com">luke.leighton@gmail.com</a></a>></span><br><span>Subject: [Arm-netbook] capacitive touchpanels</span><br><span>To: Linux on small ARM machines <<a href="mailto:arm-netbook@lists.phcomp.co.uk" x-apple-data-detectors="true"><a href="mailto:arm-netbook@lists.phcomp.co.uk">arm-netbook@lists.phcomp.co.uk</a></a>></span><br><span>Message-ID:</span><br><span> <<a href="mailto:CAPweEDxmiGzVnacmFP4d7tROg+iswj33a8aqL1ggyii011M-rQ@mail.gmail.com" x-apple-data-detectors="true"><a href="mailto:CAPweEDxmiGzVnacmFP4d7tROg+iswj33a8aqL1ggyii011M-rQ@mail.gmail.com">CAPweEDxmiGzVnacmFP4d7tROg+iswj33a8aqL1ggyii011M-rQ@mail.gmail.com</a></a>></span><br><span>Content-Type: text/plain; charset=UTF-8</span><br><span></span><br><span><a href="http://electronics.howstuffworks.com/iphone2.htm" x-apple-data-detectors="true"><a href="http://electronics.howstuffworks.com/iphone2.htm">http://electronics.howstuffworks.com/iphone2.htm</a></a></span><br><span></span><br><span>this is fascinating. and... well... kinda necesary to investigate. i</span><br><span>found out that a decent 7in tablet capacitive panel (5T) is around $22</span><br><span>to $24. this is mad prices. one that has a lot less sensor lines can</span><br><span>be had *WITHOUT* an on-board controller IC can be had for around $11.</span><br><span></span><br><span>*but* - the problem with doing that according to wikipedia is stray</span><br><span>capacitance: <a href="http://en.wikipedia.org/wiki/Capacitive_sensing#Circuit_design" x-apple-data-detectors="true"><a href="http://en.wikipedia.org/wiki/Capacitive_sensing#Circuit_design">http://en.wikipedia.org/wiki/Capacitive_sensing#Circuit_design</a></a></span><br><span></span><br><span>however, given that the price of the controller ICs is absolutely mad</span><br><span>- i'm seeing prices of $4 (!!) - it's just... i can't bring myself to</span><br><span>justify it sooooo, the idea is to use a 100-pin STM32F. 15 "scan"</span><br><span>lines (across the horizontal), and 10 "sensor" lines (going down), i</span><br><span>feel reasonably confident that this is doable, although, obviously,</span><br><span>i'm going to have to check!</span><br><span></span><br><span>what fun, eh? no proprietary ICs - just use a single controller, do</span><br><span>it all as free software :)</span><br><span></span><br><span>l.</span></blockquote><div></div></body></html>