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authorNicolas Schodet2013-04-05 23:06:50 +0200
committerNicolas Schodet2013-04-05 23:14:52 +0200
commit143327bb7e9472691718572243c0f59bb0c02086 (patch)
treead30c950c1773997d8f82ab8e3ecb8161da1b788 /digital/io-hub/src/common-cc/debounce.cc
parentcdbfdcdb5a56ef8707e2fe396fd0e5cdc1731d17 (diff)
digital/io-hub/src/apbirthday: add jack filtering
Diffstat (limited to 'digital/io-hub/src/common-cc/debounce.cc')
-rw-r--r--digital/io-hub/src/common-cc/debounce.cc46
1 files changed, 46 insertions, 0 deletions
diff --git a/digital/io-hub/src/common-cc/debounce.cc b/digital/io-hub/src/common-cc/debounce.cc
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+++ b/digital/io-hub/src/common-cc/debounce.cc
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+// io-hub - Modular Input/Output. {{{
+//
+// Copyright (C) 2013 Nicolas Schodet
+//
+// APBTeam:
+// Web: http://apbteam.org/
+// Email: team AT apbteam DOT org
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+//
+// }}}
+#include "debounce.hh"
+
+Debounce::Debounce (ucoo::Io &io, int filter_depth)
+ : io_ (io), filter_depth_ (filter_depth), state_ (io.get ()), filter_ (0)
+{
+}
+
+void
+Debounce::update ()
+{
+ bool now = io_.get ();
+ // State unchanged, reset filter.
+ if (now == state_)
+ filter_ = 0;
+ // State changed, should be kept stable for filter_depth_ updates until we
+ // accept it.
+ else if (filter_++ == filter_depth_)
+ {
+ state_ = now;
+ filter_ = 0;
+ }
+}
+