1 files changed, 57 insertions, 0 deletions

diff --git a/firmware/drivers/adc.c b/firmware/drivers/adc.c
new file mode 100644
index 0000000000..6008c14ed6
--- /dev/null
+++ b/firmware/drivers/adc.c
@@ -0,0 +1,57 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   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 "config.h"
+#include "sh7034.h"
+#include "kernel.h"
+#include "thread.h"
+#include "adc.h"
+
+static int current_channel;
+static unsigned short adcdata[NUM_ADC_CHANNELS];
+static unsigned int adcreg[NUM_ADC_CHANNELS] =
+{
+    ADDRAH_ADDR, ADDRBH_ADDR, ADDRCH_ADDR, ADDRDH_ADDR,
+    ADDRAH_ADDR, ADDRBH_ADDR, ADDRCH_ADDR, ADDRDH_ADDR
+};
+
+static void adc_tick(void)
+{
+    /* Read the data that has bee converted since the last tick */
+    adcdata[current_channel] =
+        *(unsigned short *)adcreg[current_channel] >> 6;
+
+    /* Start a conversion on the next channel */
+    current_channel++;
+    if(current_channel == NUM_ADC_CHANNELS)
+        current_channel = 0;
+    ADCSR = ADCSR_ADST | current_channel;
+}
+
+unsigned short adc_read(int channel)
+{
+    return adcdata[channel];
+}
+
+void adc_init(void)
+{
+    ADCR  = 0; /* No external trigger */
+    
+    current_channel = 0;
+    tick_add_task(adc_tick);
+}