--- /dev/null
+# MegaMetrum
+
+This is a high-end recording dual-deploy altimeter for high power model
+rocketry with integrated GPS and telemetry link. The features included
+make MegaMetrum the ideal choice for complex projects including sustainers
+on multi-stage projects.
+
+For the latest MegaMetrum firmware and related ground station software, please
+visit the [AltOS](../AltOS) page on this site.
+
+These are no photos of MegaMetrum to share yet.
+
+## Features ##
+
+### User View ###
+
+* Recording altimeter for high power model rocketry
+* Supports dual deployment and additional pyro events (can fire 6 charges)
+* 70cm ham-band transceiver for telemetry downlink
+* Barometric pressure sensor good to 100k feet MSL
+* 1-axis 105-g accelerometer for motor characterization
+* 3-axis 18-g accelerometer for gyro calibration
+* 3-axis 2000 deg/sec gyros
+* 3-axis magnetic sensor
+* On-board, integrated GPS receiver
+* On-board non-volatile memory for flight data storage
+* USB for power, configuration, and data recovery
+* Integrated support for LiPo rechargeable batteries
+* Uses LiPo to fire e-matches, can be factory modified to support separate pyro battery
+* 3.25 x 1.25 inch board designed to fit inside 38mm airframe coupler tube
+
+### Developer View ###
+
+* Hardware Features
+ * ST Micros [STM32L151](http://www.st.com/internet/mcu/product/248821.jsp) ARM Cortex M3 based Microcontroller
+ * TI [CC1120](http://www.ti.com/product/cc1120) High Performance RF Transceiver for Narrowband Systems
+ * 150mA 3.3V LDO regulator
+ * takes input from USB interface by default
+ * output appears on 8-pin companion connector
+ * can take input from 8-pin companion connector in non-USB applications
+ * [Winbond W25Q64CV](http://www.winbond.com/hq/enu/ProductAndSales/ProductLines/FlashMemory/SerialFlash/W25Q64CV.htm) serial flash memory
+ * [SkyTraq](http://www.skytraq.com.tw/) Venus634FLPx GPS receiver
+ * on-board [Taoglas AP.17A.01](http://www.taoglas.com/antennas/GPS_Antennas/Internal_GPS_-_Active_Patch_Modules/)
+ single-stage active patch antenna
+ * U.FL connector with 3.3V DC can be re-purposed for optional external amplified antennas
+ * async serial interface
+ * Measurement Specialties [MS5607](http://www.meas-spec.com/product/t_product.aspx?id=8499) Micro Altimeter Module
+ * Wide range — 120kPa to 1kPa (approximately -1500m to 31000m)
+ * High precision — 2.4Pa resolution (approximately 20cm at sea level)
+ * Factory calibrated.
+ * Freescale [MMA655x](http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MMA65xx&fsrch=1&sr=1) Single Axis SPI Intertial Sensor
+ * +- 105g or 120g full-scale
+ * on-chip 12-bit digitizer
+ * Invensense [MPU-6000](http://invensense.com/mems/gyro/mpu6050.html) Six-Axis MEMS Motion Tracking Device
+ * tri-axis angular rate sensor up to 2000 degrees/second
+ * tri-axis accelerometer with +- 16g range
+ * three on-chip ADCs for true simultaneous sampling of all axes
+ * Honeywell [HMC5883L](http://www.magneticsensors.com/three-axis-digital-compass.php) 3-Axis Digital Compass IC
+* Software Features
+ * Written mostly in C with some ARM assembler
+ * Runs from on-chip flash, uses on-chip RAM, stores flight data to serial flash
+ * USB serial emulation for "console" interface
+* Tools Used
+ * [gEDA](http://www.gpleda.org/) for schematic capture and PCB layout
+* Licenses
+ * The hardware is licensed under the [TAPR](http://www.tapr.org) [Open Hardware License](http://www.tapr.org/ohl.html)
+ * The software is licensed [GPL version 2](http://www.gnu.org/licenses/old-licenses/gpl-2.0.html)
+
+## Artifacts ##
+
+There is a single manual for MegaMetrum and most other Altus Metrum products,
+which is available in [html](../AltOS/doc/altusmetrum.html) and
+[pdf](../AltOS/doc/altusmetrum.pdf) formats.
+
+The hardware design current gEDA files are available from
+[git.gag.com](http://git.gag.com) in the project
+[hw/megametrum](http://git.gag.com/?p=hw/megametrum;a=summary).
+
+## Future Plans ##
+
+MegaMetrum v0.1 prototypes are working and flight testing is underway.
+
+There will be at least one more prototype version to try out a different
+GPS receiver and improve various design details... most likely at least
+2 more prototype versions before we go to production.
+
+No firm schedule for production and sale of MegaMetrum has been set yet,
+but we hope to offer this product in time for the 2013 flying season.