A modern, tiny, and hackable altimeter for hobby rocketry. Features include:

* Fits in a min-diameter 29mm rocket

* High accuracy barometric pressure sensor (up to ~9km)

* Dual deploy capable (two pyro channels)

* Visual continuity LEDs

* On-board 1MB storage

 * Altitude measurements

 * Flight events (ascent, apogee, landing, etc.)

 * Deployment events

* Mach dip filtering (works on flights that break Mach)

* Audio arming indicator

* Bluetooth connection

 * Deployment testing with flight simulations over BLE

 * Configuration over BLE

 * Continuity & other telemetry over BLE

* WiFi capable

## Firmware

The firmware for this board is made using the [Apache NuttX RTOS][nuttx-site],

an open-source embedded RTOS with an incredible community and an excellent

feature set.

Firmware is spread across a few repositories. If you are compiling yourself,

you'll need:

- [The NuttX kernel source][nuttx]

- [The NuttX application library][nuttx-apps]

- The Peanut board support package (coming soon)

- [My application-level altimeter software][rocket-altimeter]

## Hackability

All hardware designs & firmware for Peanut are open-sourced and available under

permissive licensing.

The device itself is programmable over the USB-C interface, so users can tweak

the firmware or write their own and re-program the device. Want the buzzer to

play custom audio? Want to change the meaning of the "START" LED? Want to add

more features to the Bluetooth interface, or make the altimeter operate over

WiFi instead? You can program whatever you want into it.

## Make Your Own

If you want to make your own Peanut Altimeter, the component cost for the board

is roughly $30 CAD. You can get PCB blanks from a manufacturer of your choice

(PCBWay). You should only need to verify the trace widths of the

Bluetooth RF trace depending on the differences between your manufacturer's

PCB stackup and mine.

**NOTE:** This board was not designed with hand-soldering in mind (aside from

the backside). My manufacture process is to use solder paste, a stencil and a

hot plate to do the top-side components. There are 0402 components which are

manageable with steady hands and tweezers.

[nuttx]: https://github.com/apache/nuttx

[nuttx-apps]: https://github.com/apache/nuttx-apps

[nuttx-site]: https://nuttx.apache.org/

[rocket-altimeter]: https://github.com/linguini1/rocket-altimeter