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Diffstat (limited to 'n/asserv/src/pwm.c')
-rw-r--r--n/asserv/src/pwm.c77
1 files changed, 46 insertions, 31 deletions
diff --git a/n/asserv/src/pwm.c b/n/asserv/src/pwm.c
index 84791d4..7979842 100644
--- a/n/asserv/src/pwm.c
+++ b/n/asserv/src/pwm.c
@@ -1,8 +1,12 @@
/* pwm.c */
-/* {{{
+/* asserv - Position & speed motor control on a ATmega128. {{{
*
* Copyright (C) 2004 Nicolas Schodet
*
+ * Robot APB Team/Efrei 2005.
+ * Web: http://assos.efrei.fr/robot/
+ * Email: robot AT efrei DOT fr
+ *
* 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
@@ -17,17 +21,29 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
- * Contact :
- * Web: http://perso.efrei.fr/~schodet/
- * Email: <contact@ni.fr.eu.org>
* }}} */
-#include "pwm.h"
-#include <avr/io.h>
+
+/* PWM values. */
+int16_t pwm_left, pwm_right;
/* +AutoDec */
+
+/** Initialise PWM generator. */
+static inline void
+pwm_init (void);
+
+/** Preprocess a PWM value before sending it to hardware. */
+static inline uint8_t
+pwm_preproc (uint16_t v);
+
+/** Update the hardware PWM values. */
+static inline void
+pwm_update (void);
+
/* -AutoDec */
-inline void
+/** Initialise PWM generator. */
+static inline void
pwm_init (void)
{
/* No timer/counter interrupt. */
@@ -42,51 +58,50 @@ pwm_init (void)
DDRB |= _BV (7) | _BV (6) | _BV (3) | _BV (2);
}
-static inline int16_t
-pwm_preproc (int16_t v)
+/** Preprocess a PWM value before sending it to hardware. */
+static inline uint8_t
+pwm_preproc (uint16_t v)
{
- v = (v >> 2) + ((v >> 1) & 1);
- /*if (v > 0)
- v += 0x0f;
- else if (v < 0)
- v -= 0x0f;*/
+ v += 0x10;
if (v > 255)
return 255;
- else if (v < -255)
- return -255;
else
return v;
}
-inline void
-pwm_set_left (int16_t v)
+/** Update the hardware PWM values. */
+static inline void
+pwm_update (void)
{
- v = pwm_preproc (v);
- if (v < 0)
+ /* Set left PWM. */
+ if (pwm_left == 0)
+ {
+ OCR1B = 0;
+ }
+ else if (pwm_left < 0)
{
PORTB &= ~_BV (2);
- OCR1B = -v;
+ OCR1B = pwm_preproc (-pwm_left);
}
else
{
PORTB |= _BV (2);
- OCR1B = v;
+ OCR1B = pwm_preproc (pwm_left);
}
-}
-
-inline void
-pwm_set_right (int16_t v)
-{
- v = pwm_preproc (v);
- if (v < 0)
+ /* Set right PWM. */
+ if (pwm_right == 0)
+ {
+ OCR1C = 0;
+ }
+ else if (pwm_right < 0)
{
PORTB |= _BV (3);
- OCR1C = -v;
+ OCR1C = pwm_preproc (-pwm_right);
}
else
{
PORTB &= ~_BV (3);
- OCR1C = v;
+ OCR1C = pwm_preproc (pwm_right);
}
}