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authorJérémy Dufour2008-03-27 23:38:47 +0100
committerJérémy Dufour2008-03-27 23:38:47 +0100
commitb2f7ae8308ae0d4e3baaca34869b7e01f3432d0e (patch)
tree2e8dc4f4f52f823645abf70ea22f3dc61c4f303b /digital/io/src
parentf4d29f0c30e8af182de049f06ef3ef939f255309 (diff)
* digital/io/src
- add chrono module to manage the duration of a match.
Diffstat (limited to 'digital/io/src')
-rw-r--r--digital/io/src/chrono.h81
1 files changed, 81 insertions, 0 deletions
diff --git a/digital/io/src/chrono.h b/digital/io/src/chrono.h
new file mode 100644
index 00000000..f28d67ef
--- /dev/null
+++ b/digital/io/src/chrono.h
@@ -0,0 +1,81 @@
+#ifndef chrono_h
+#define chrono_h
+/* chrono.h */
+/* io - Input & Output with Artificial Intelligence (ai) support on AVR. {{{
+ *
+ * Copyright (C) 2008 Dufour Jrmy
+ *
+ * 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.
+ *
+ * }}} */
+
+/**
+ * @file Module to manage the chrono responsible to stop the bot after 90s.
+ * It uses the timer/counter 1 (16 bits), configured with a prescaler set to
+ * 256.
+ * This way, we need to overflow 79.10071 for a match of 90s:
+ * match_duration / (1 / (AC_FREQ / (Prescaler * (TOP + 1))))
+ * It will overflow 79 times and them reset the timer/counter to 58982
+ * (TOP - ((TOP + 1) / 10)).
+ */
+
+#include "modules/utils/utils.h" /* regv */
+#include "io.h" /* Registers for timer/counter 1 */
+
+/**
+ * Match is finished.
+ * This variable will be set to 0 when the match is over.
+ */
+static uint8_t chrono_match_over;
+
+/**
+ * Overflow counter.
+ */
+static uint8_t chrono_ov_count_;
+
+/**
+ * Initialize the chrono timer/counter 1.
+ */
+static inline void
+chrono_init (void)
+{
+ /* Presaler = 256 */
+ TCCR1B = regv (ICNC1, ICES1, 5, WGM13, WGM12, CS12, CS11, CS10,
+ 0, 1, 0, 0, 0, 1, 0, 0);
+ /* Enable overflow interrupt */
+ set_bit (TIMSK, TOIE1);
+}
+
+/* Overflow of timer/counter 1 handler. */
+SIGNAL (SIG_OVERFLOW1)
+{
+ switch (++chrono_ov_count_)
+ {
+ case 70:
+ /* Last but not complete overflow */
+ TCNT1 = 58982;
+ break;
+ case 71:
+ /* End of match! */
+ chrono_match_over = 1;
+ break;
+ }
+}
+
+#endif /* chrono_h */