Tick timer additions

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@219 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 63 insertions, 0 deletions

diff --git a/firmware/test/kernel/timer.c b/firmware/test/kernel/timer.c
new file mode 100644
index 0000000..be253db
--- /dev/null
+++ b/firmware/test/kernel/timer.c
@@ -0,0 +1,63 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2002 by Linus Nielsen Feltzing
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include "sh7034.h"
+#include "system.h"
+#include "debug.h"
+
+void tick_start(unsigned int interval_in_ms)
+{
+    unsigned int count;
+
+    count = FREQ / 1000 / 8 * interval_in_ms;
+
+    if(count > 0xffff)
+    {
+	debugf("Error! The tick interval is too long (%d ms)\n",
+	       interval_in_ms);
+	return;
+    }
+    
+    /* We are using timer 0 */
+    
+    TSTR &= ~0x01; /* Stop the timer */
+    TSNC &= ~0x01; /* No synchronization */
+    TMDR &= ~0x01; /* Operate normally */
+
+    TCNT0 = 0;   /* Start counting at 0 */
+    GRA0 = 0xfff0;
+    TCR0 = 0x23; /* Clear at GRA match, sysclock/8 */
+
+    TSTR |= 0x01; /* Start timer 1 */
+
+    /* Enable interrupt on level 1 */
+    IPRC = (IPRC & ~0x00f0) | 0x0010;
+
+    TIER0 |= 0x01; /* Enable GRA match interrupt */
+    
+    while(1)
+    {
+    }
+}
+
+#pragma interrupt
+void IMIA0(void)
+{
+    TSR0 &= ~0x01;
+    debugf("Yes\n");
+}