[[!meta title="EasyMini"]]
# EasyMini

This is a small, baro-only recording dual-deploy altimeter for 
model rocketry

EasyMini version 3.0 is available from the
[Garbee and Garbee](https://shop.gag.com) web store
and from our distributors.

For the latest EasyMini firmware and related ground station software,
please visit the [AltOS](../AltOS) page on this site.  EasyMini
version 3.0 requires AltOS version 1.9.12 or later.

These are photos of version 3.0:

<a href="v3.0/top.jpg"> <img src="v3.0/top-thumb.jpg"></a>
<a href="v3.0/bottom.jpg"> <img src="v3.0/bottom-thumb.jpg"></a>

## Features ##

### User View ###

* Recording altimeter for model rocketry
* Supports dual deployment (can fire 2 ejection charges)
* Barometric pressure sensor good to 100k feet MSL
* Designed to use a battery supplying 3.7V-12V.
* 1.5 x 0.8 inch board designed to fit inside 24mm airframe coupler tube
* 1MB on-board data logging flash
* Weighs only 6.5g (less than 1/4 oz)

### Developer View ###

* Hardware Features
	* [NXP LPC11U24](https://www.nxp.com/part/LPC11U24FET48#/) System-on-Chip.
		* ARM Cortex-M0 MCU
		* 32k Flash
		* 8k RAM
		* USB 2.0
		* 10-bit analog inputs
		* I2C, SPI, async serial
		* digital I/O
	* [Measurement Specialties MS5607](http://www.meas-spec.com/product/pressure/MS5607-02BA03.aspx) pressure sensor
	* 1MB SPI flash
* Software Features
	* Written mostly in C with some ARM assembler
	* Runs from on-chip flash, uses on-chip RAM, stores flight data to
		flash memory part
* Tools Used
	* [lepton-eda](https://github.com/lepton-eda/lepton-eda) for schematic capture
	* [pcb-rnd](http://repo.hu/projects/pcb-rnd/) for PCB layout
	* [GCC](http://gcc.gnu.org/) compiler and source debugger
* 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 shorter manual for EasyMini which is available in
[html](../AltOS/doc/easymini.html) and
[pdf](../AltOS/doc/easymini.pdf) formats. EasyMini is also documented
in the comprehensive Altus Metrum manual in
[html](../AltOS/doc/altusmetrum.html) and
[pdf](../AltOS/doc/altusmetrum.pdf) formats

An outline of the board with drill hole locations is available in
[pdf](../AltOS/doc/easymini-outline.pdf) format.

Thanks to Bryan Duke, there's also a 3d model of EasyMini available on 
[Thingiverse](http://www.thingiverse.com/thing:1946852). 

The hardware design files can be found on [git.gag.com](http://git.gag.com) 
in the project [hw/easymini](http://git.gag.com/?p=hw/easymini;a=summary).  

For those who don't have ready access to the gEDA suite, here are pdf snapshots
of the files for production PCB version 3.0 in pdf format.  

* [schematic](v3.0/easymini-sch.pdf)
* [pcb artwork](v3.0/easymini-pcb.pdf)
* [bill of materials](v3.0/partslist.csv)

## Previous Versions ##

All versions of EasyMini have the same user-visible features and 
specifications, the differences are primarily in the choice of processor which
has changed over time due to availability.  

Easy Mini version 1.0 was the first production version of EasyMini, based on 
the [NXP LPC11U14](http://www.nxp.com/products/microcontrollers/cortex_m0_m0/LPC11U14FHI33.html) System-on-Chip.

Easy Mini version 2.0 was the second production version of EasyMini, 
based on the 
[STM32F042](http://www.st.com/en/microcontrollers/stm32f042f6.html)
System-on-Chip.  This version also moved to a more robust USB connector.

Easy Mini version 1.1 was the third production version of EasyMini.  It used
the more robust USB connector, but went back to the same processor chip as
version 1.0 due to parts availability.