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-rw-r--r--n/asserv/src/dsp.c41
1 files changed, 28 insertions, 13 deletions
diff --git a/n/asserv/src/dsp.c b/n/asserv/src/dsp.c
index 71317a5..9520513 100644
--- a/n/asserv/src/dsp.c
+++ b/n/asserv/src/dsp.c
@@ -1,8 +1,12 @@
/* dsp.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
@@ -17,18 +21,15 @@
* 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 "dsp.h"
/* +AutoDec */
/* -AutoDec */
-/* Add two signed words and saturate. */
-inline int16_t
-dsp_i16i16_add_sat (int16_t a, int16_t b)
+/** Add two signed words and saturate. UNTESTED. */
+extern inline int16_t
+dsp_add_sat_i16i16 (int16_t a, int16_t b)
{
asm ("add %A0, %A1\n\t"
"adc %B0, %B1\n\t"
@@ -42,14 +43,28 @@ dsp_i16i16_add_sat (int16_t a, int16_t b)
/* Load Min. */
"ldi %A0, 0x00\n\t"
"ldi %B0, 0x80\n\t"
- "1f" "\n\t"
- : "=r" a : "0" a, "r" b);
+ "1:" "\n\t"
+ : "=r" (a) : "0" (a), "r" (b));
return a;
}
-/* Multiply and saturate. */
-inline int16_t
-dsp_i16u8_mul_sat (int16_t a, uint8_t b)
+/** Multiply signed 16 by fixed 8.8. */
+extern inline int16_t
+dsp_mul_i16f88 (int16_t a, uint16_t b)
{
- asm ("mul
+ int16_t r;
+ asm ("mulsu %B1, %B2\n\t"
+ "mov %B0, r0\n\t"
+ "mul %A1, %A2\n\t"
+ "mov %A0, r1\n\t"
+ "mul %A1, %B2\n\t"
+ "add %A0, r0\n\t"
+ "adc %B0, r1\n\t"
+ "mulsu %B1, %A2\n\t"
+ "add %A0, r0\n\t"
+ "adc %B0, r1\n\t"
+ "clr r1\n\t"
+ : "=&r" (r) : "a" (a), "a" (b) : "r0", "r1");
+ return r;
}
+