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diff --git a/digital/asserv/src/avrcounter/avrcounter-port-one.c b/digital/asserv/src/avrcounter/avrcounter-port-one.c
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+/* avrcounter-port-one.c - Single encoder, port output. */
+/* avrcounter - Incremental encoder counter. {{{
+ *
+ * Copyright (C) 2007 Nicolas Schodet
+ *
+ * Robot APB Team 2008.
+ * 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 <io.h>
+
+int
+main (void)
+{
+ uint8_t count = 0;
+ uint8_t state = 0;
+ /* Encoder signals:
+ * ____----____----____----
+ * __----____----____----__ */
+ static const int8_t inc[] = {
+ 0, /* 00 -> 00 */
+ +1, /* 00 -> 01 */
+ -1, /* 00 -> 10 */
+ 0, /* 00 -> 11, missed! */
+ -1, /* 01 -> 00 */
+ 0, /* 01 -> 01 */
+ 0, /* 01 -> 10, missed! */
+ +1, /* 01 -> 11 */
+ +1, /* 10 -> 00 */
+ 0, /* 10 -> 01, missed! */
+ 0, /* 10 -> 10 */
+ -1, /* 10 -> 11 */
+ 0, /* 11 -> 00, missed! */
+ -1, /* 11 -> 01 */
+ +1, /* 11 -> 10 */
+ 0, /* 11 -> 11 */
+ };
+ DDRD = 0xff;
+ while (1)
+ {
+ state = (state << 2) | (PINC & 0x03);
+ count += inc[state];
+ PORTD = count;
+ }
+}