--- /dev/null
+/*
+ * Copyright © 2011 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 __data union {
+ uint8_t d[2];
+ int16_t v;
+} ao_battery_value;
+
+void
+ao_battery_isr(void) ao_arch_interrupt(1)
+{
+ ao_battery_value.d[0] = ADCL;
+ ao_battery_value.d[1] = ADCH;
+ ao_wakeup(DATA_TO_XDATA(&ao_battery_value));
+}
+
+uint16_t
+ao_battery_get(void)
+{
+ ao_arch_critical(
+ ADCCON3 = ADCCON3_EREF_VDD | ADCCON3_EDIV_512 | BATTERY_PIN;
+ ao_sleep(DATA_TO_XDATA(&ao_battery_value));
+ );
+ return (uint16_t) ((int32_t) ao_battery_value.v * (int32_t) 3333 >> 15);
+}
+
+static void
+ao_battery_show(void)
+{
+ printf("Battery: %u mV\n", ao_battery_get());
+}
+
+__code struct ao_cmds ao_battery_cmds[] = {
+ { ao_battery_show, "B\0Show battery voltage" },
+ { 0, NULL },
+};
+
+void
+ao_battery_init(void)
+{
+ ADCCFG = (1 << BATTERY_PIN);
+ ADCIF = 0;
+ IEN0 |= IEN0_ADCIE;
+ ao_cmd_register(&ao_battery_cmds[0]);
+}