summaryrefslogtreecommitdiffhomepage
path: root/digital
diff options
context:
space:
mode:
authorJérémy Dufour2008-03-27 23:38:26 +0100
committerJérémy Dufour2008-03-27 23:38:26 +0100
commitf4d29f0c30e8af182de049f06ef3ef939f255309 (patch)
treeb2134ec498f4373e51deb99dca7600ce403e9bd6 /digital
parentcf45668e3f5f7c18954555185fde0d7906e610aa (diff)
* digital/io/src
- add sharp module with hysteresis support.
Diffstat (limited to 'digital')
-rw-r--r--digital/io/src/Makefile4
-rw-r--r--digital/io/src/sharp.c162
-rw-r--r--digital/io/src/sharp.h109
3 files changed, 273 insertions, 2 deletions
diff --git a/digital/io/src/Makefile b/digital/io/src/Makefile
index 428f2418..1ea16d6f 100644
--- a/digital/io/src/Makefile
+++ b/digital/io/src/Makefile
@@ -1,7 +1,7 @@
BASE = ../../avr
AVR_PROGS = io
-io_SOURCES = main.c asserv.c servo.c eeprom.c trap.c
-MODULES = proto uart twi
+io_SOURCES = main.c asserv.c servo.c eeprom.c trap.c sharp.c
+MODULES = proto uart twi utils adc
CONFIGFILE = avrconfig.h
# atmega8, atmega8535, atmega128...
AVR_MCU = atmega128
diff --git a/digital/io/src/sharp.c b/digital/io/src/sharp.c
new file mode 100644
index 00000000..1a3084a7
--- /dev/null
+++ b/digital/io/src/sharp.c
@@ -0,0 +1,162 @@
+/* sharp.c */
+/* 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.
+ *
+ * }}} */
+
+#include "sharp.h"
+
+#include "modules/adc/adc.h" /* ADC functions */
+#include "io.h"
+
+/**
+ * Cached array of raw sharp values.
+ */
+uint16_t sharp_values_[SHARP_NUMBER];
+
+/**
+ * Low (0 index) and high (1 index) thresholds for interpreted sharp values.
+ */
+uint16_t sharp_threshold[SHARP_NUMBER][2];
+
+/**
+ * Hysteresis.
+ */
+uint8_t sharp_hysteresis_[SHARP_NUMBER];
+
+/**
+ * Hysteresis threshold.
+ */
+#define SHARP_HYSTERESIS_THRESHOLD 3
+
+/**
+ * Previous sharp interpreted values.
+ */
+uint8_t sharp_previous_values_[SHARP_NUMBER];
+
+/* Initialize sharp module. */
+void
+sharp_init (void)
+{
+ /* Pins are in input mode by default */
+
+ /* ADC initialize */
+ adc_init ();
+}
+
+/* Update read data from sharps. */
+void
+sharp_update (uint8_t sharp_mask)
+{
+ uint8_t compt;
+
+ /* Go through the bit mask */
+ for (compt = 0; compt < SHARP_NUMBER; compt++)
+ {
+ /* Check if the bit/sharp id is set */
+ if (bit_is_set (sharp_mask, compt))
+ {
+ /* Start the capture */
+ adc_start (compt + 1);
+ /* Wait until ADC mesure is finished */
+ while (!adc_checkf ())
+ ;
+ /* Store the value */
+ sharp_values_[compt] = adc_read ();
+ }
+ }
+}
+
+/* Get raw cached data from sharps. */
+uint16_t
+sharp_get_raw (uint8_t sharp_id)
+{
+ /* Sanity check */
+ if (sharp_id < SHARP_NUMBER)
+ /* Return raw cached value */
+ return sharp_values_[sharp_id];
+ return 0;
+}
+
+/* Configure the thresholds of a sharp. */
+void
+sharp_set_threshold (uint8_t sharp_id, uint16_t low, uint16_t high)
+{
+ /* Sanity check */
+ if (sharp_id < SHARP_NUMBER)
+ {
+ /* Set low and high threshold */
+ sharp_threshold[sharp_id][0] = low;
+ sharp_threshold[sharp_id][1] = high;
+ }
+}
+
+/* Get interpreted value from sharps. */
+uint8_t
+sharp_get_interpreted (uint8_t sharp_id)
+{
+ uint8_t current_state;
+
+ /* Sanity check */
+ if (sharp_id < SHARP_NUMBER)
+ {
+ /* Check if sharp state is lower than the low threshold */
+ if (sharp_values_[sharp_id] < sharp_threshold[sharp_id][0])
+ /* Update current state seen by the sharp */
+ current_state = 0;
+ /* Check if sharp state is higher than the high threshold */
+ else if (sharp_values_[sharp_id] > sharp_threshold[sharp_id][1])
+ /* Update current state seen by the sharp */
+ current_state = 1;
+ /* In the middle */
+ else
+ /* Return the previous value */
+ return sharp_previous_values_[sharp_id];
+
+ /* Manage the hysteresis */
+ /* Check if previous value is the current state */
+ if (sharp_previous_values_[sharp_id] == current_state)
+ {
+ /* Reset hysteresis */
+ sharp_hysteresis_[sharp_id] = SHARP_HYSTERESIS_THRESHOLD;
+ /* Return current state */
+ return current_state;
+ }
+ /* Otherwise, check if this sharp value has been the same
+ * SHARP_HYSTERESIS_THRESHOLD times */
+ else if (sharp_hysteresis_[sharp_id]-- == 0)
+ {
+ /* Current value change (for SHARP_HYSTERESIS_THRESHOLD times)! */
+ /* Update previous value */
+ sharp_previous_values_[sharp_id] = current_state;
+ /* Reset hysteresis */
+ sharp_hysteresis_[sharp_id] = SHARP_HYSTERESIS_THRESHOLD;
+ /* Return current state */
+ return current_state;
+ }
+ else
+ /* Return previous state */
+ return sharp_previous_values_[sharp_id];
+ }
+ /* Error */
+ return 2;
+}
diff --git a/digital/io/src/sharp.h b/digital/io/src/sharp.h
new file mode 100644
index 00000000..ef48969a
--- /dev/null
+++ b/digital/io/src/sharp.h
@@ -0,0 +1,109 @@
+#ifndef sharp_h
+#define sharp_h
+/* sharp.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 control distance measuring sensors (sharp).
+ * They can be used to detect obstacles, for example a bot.
+ * It uses the Analog to Digital Converter (ADC) of the AVR to read and
+ * understand data from the sharp sensors.
+ * This module keep a value of the last read values from the sharp and update
+ * it when calling the correct function.
+ */
+
+#include "common.h" /* uint*_t */
+
+/**
+ * Number of sharps.
+ */
+#define SHARP_NUMBER 6
+
+/**
+ * Front left sharp.
+ */
+#define SHARP_FRONT_LEFT _BV(0)
+
+/**
+ * Front right sharp.
+ */
+#define SHARP_FRONT_RIGHT _BV(1)
+
+/**
+ * Back left sharp.
+ */
+#define SHARP_BACK_LEFT _BV(2)
+
+/**
+ * Back right sharp.
+ */
+#define SHARP_BACK_RIGHT _BV(3)
+
+/**
+ * Low (0 index) and high (1 index) thresholds for interpreted sharp values.
+ */
+extern uint16_t sharp_threshold[SHARP_NUMBER][2];
+
+/**
+ * Initialize sharp module.
+ */
+void sharp_init (void);
+
+/**
+ * Update read data from sharps.
+ * This function is blocking. To get the value you have to use the get
+ * function (@a sharp_get_raw).
+ * @param sharp_mask list of sharps (using a mask) to update.
+ */
+void sharp_update (uint8_t sharp_mask);
+
+/**
+ * Get raw cached data from sharps.
+ * It read the cached data (updated by the @a sharp_update function).
+ * @param sharp_id the sharp id to get raw data from.
+ * @return the raw data read from the sharps (0 is a non valid value).
+ */
+uint16_t sharp_get_raw (uint8_t sharp_id);
+
+/**
+ * Configure the thresholds of a sharp.
+ * @param sharp_id the sharp id to configure the thresholds.
+ * @param low low threshold of the sharp.
+ * @param high high threshold of the sharp.
+ */
+void sharp_set_threshold (uint8_t sharp_id, uint16_t low, uint16_t high);
+
+/**
+ * Get interpreted value from sharps.
+ * It is used to know if there is something in front of the sharp.
+ * @param sharp_id the sharp number to get interpreted value from.
+ * @return
+ * - 0 if there is nothing in front of the sharp.
+ * - 1 if there is something in front of the sharp;
+ * - other values when error occurs.
+ */
+uint8_t sharp_get_interpreted (uint8_t sharp_id);
+
+#endif /* sharp_h */