altos: Log baro readings for MicroPeak

This logs barometric data every 192ms (more or less) to the 504
remaining bytes of internal EEPROM storage in the ATtiny85. This
provides 48.192 seconds of logging.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/src/micropeak/ao_micropeak.h b/src/micropeak/ao_micropeak.h
new file mode 100644
index 00000000..e408d7c5
--- /dev/null
+++ b/src/micropeak/ao_micropeak.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright © 2012 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.
+ */
+
+#ifndef _AO_MICROPEAK_H_
+#define _AO_MICROPEAK_H_
+
+#define FILTER_SHIFT		3
+#define SAMPLE_SLEEP		AO_MS_TO_TICKS(96)
+
+/* 16 sample, or about two seconds worth */
+#define GROUND_AVG_SHIFT	4
+#define GROUND_AVG		(1 << GROUND_AVG_SHIFT)
+
+/* Pressure change (in Pa) to detect boost */
+#define BOOST_DETECT		120	/* 10m at sea level, 12m at 2000m */
+
+/* Wait after power on before doing anything to give the user time to assemble the rocket */
+#define BOOST_DELAY		AO_SEC_TO_TICKS(30)
+
+/* Pressure change (in Pa) to detect landing */
+#define LAND_DETECT		12	/* 1m at sea level, 1.2m at 2000m */
+
+/* Current sensor pressure value */
+extern uint32_t	pa;
+
+/* IIR filtered pressure value */
+extern uint32_t	pa_avg;
+
+/* Average pressure value on ground */
+extern uint32_t	pa_ground;
+
+/* Minimum recorded filtered pressure value */
+extern uint32_t	pa_min;
+
+/* Pressure values converted to altitudes */
+extern alt_t	ground_alt, max_alt;
+
+/* max_alt - ground_alt */
+extern alt_t	ao_max_height;
+
+#endif
+