On Fri, Dec 19, 2008 at 2:57 PM, Tim <ignored_mailbox yahoo com au>
On Wed, 2008-12-17 at 05:45 -0200, Paulo Cavalcanti wrote:In some computers, there's no "detecting" at all. It's a mechanical
> Unfortunately, some boards only detect the presence of jacks connected
> to the back of the computer. Plugging, say a headphone, to the front
> does not change anything.
switch in the headphone socket, and the front and rear panel sockets are
often different (e.g. a simple one on the front).
Detecting a connection made to *any* socket, without requiring special
sockets, would require electronics designed for that (detecting a DC
change, impedance loading change, etc.).
You are right.
In fact, the problem was my computer case connectors, for the front panel.
I found out later that there are two types of Header connectors:
AC97 and HDA. The new standard, HDA, allows jack detection.
But the majority of computer cases still come with the old AC97 Header,
which does not allow jack detection:
Please, see figures on page 20 and 25 of the link below.http://www.formfactors.org/developer/specs/A2928604-005.pdf