Use autotools, move altos to src subdir

[fw/altos] / src / ao_timer.c

diff --git a/src/ao_timer.c b/src/ao_timer.c
new file mode 100644 (file)
index 0000000..81c3b37
--- /dev/null
+++ b/src/ao_timer.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright © 2009 Keith Packard <keithp@keithp.com>
+ *
+ * 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; version 2 of the License.
+ *
+ * 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 "ao.h"
+
+static volatile __data uint16_t ao_tick_count;
+
+uint16_t ao_time(void) __critical
+{
+       return ao_tick_count;
+}
+
+void
+ao_delay(uint16_t ticks)
+{
+       uint16_t until = ao_time() + ticks;
+
+       while ((int16_t) (until - ao_time()) > 0)
+               ao_sleep(DATA_TO_XDATA(&ao_tick_count));
+}
+
+#define T1_CLOCK_DIVISOR       8       /* 24e6/8 = 3e6 */
+#define T1_SAMPLE_TIME         30000   /* 3e6/30000 = 100 */
+
+volatile __data uint8_t        ao_adc_interval = 1;
+volatile __data uint8_t        ao_adc_count;
+
+void ao_timer_isr(void) interrupt 9
+{
+       ++ao_tick_count;
+       if (++ao_adc_count == ao_adc_interval) {
+               ao_adc_count = 0;
+               ao_adc_poll();
+       }
+       ao_wakeup(DATA_TO_XDATA(&ao_tick_count));
+}
+
+void
+ao_timer_set_adc_interval(uint8_t interval) __critical
+{
+       ao_adc_interval = interval;
+       ao_adc_count = 0;
+}
+
+void
+ao_timer_init(void)
+{
+       /* NOTE:  This uses a timer only present on cc1111 architecture. */
+
+       /* disable timer 1 */
+       T1CTL = 0;
+
+       /* set the sample rate */
+       T1CC0H = T1_SAMPLE_TIME >> 8;
+       T1CC0L = (uint8_t) T1_SAMPLE_TIME;
+
+       T1CCTL0 = T1CCTL_MODE_COMPARE;
+       T1CCTL1 = 0;
+       T1CCTL2 = 0;
+
+       /* clear timer value */
+       T1CNTL = 0;
+
+       /* enable overflow interrupt */
+       OVFIM = 1;
+       /* enable timer 1 interrupt */
+       T1IE = 1;
+
+       /* enable timer 1 in module mode, dividing by 8 */
+       T1CTL = T1CTL_MODE_MODULO | T1CTL_DIV_8;
+}