[[!meta title="MicroPeakUSB"]]
<img src="../logos/micropeak-usb-oneline.svg" height="100"/>

# MicroPeak USB Interface #

The MicroPeak USB Interface board provides a way to capture
[MicroPeak](../MicroPeak/) flight logs over a USB connection to a
computer running Linux, Mac OS or Windows.

<a href="v2.0/MicroPeakUSB-2.0.jpg"><img src="v2.0/MicroPeakUSB-2.0-640.jpg"></a>

## MicroPeak Data ##

 * Stored in on-chip 512B eeprom
 * Records raw barometer readings every 192ms
 * Enough storage for 48 seconds

No changes are needed to the [MicroPeak](../MicroPeak/) hardware, but new firmware that
includes the data download feature is necessary to use the MicroPeak
USB Interface.

## MicroPeak Interface ##

[MicroPeak](../MicroPeak/) transmits the entire flight log via the LED just after
reporting the last flight altitude at power up. The data burst is
transmitted in a simple serial format at 9600 baud.

The MicroPeak USB Interface board contains a phototransistor,
op-amp and serial-to-USB interface chip. It also includes a blue LED
which blinks in time with the [MicroPeak](../MicroPeak/) orange LED. This makes
aligning the two boards by hand quite easy.

<a href="v2.0/MicroPeakUSB-2.0-bundle.jpg"><img src="v2.0/MicroPeakUSB-2.0-bundle-640.jpg"></a>

Here's a picture of the device in operation, with
[MicroPeak](../MicroPeak) positioned to transmit data. The blue LED on
the interface board is visible through the smaller hole in the front
of the box.

<a href="v2.0/MicroPeakUSB-2.0-inuse.jpg"><img src="v2.0/MicroPeakUSB-2.0-inuse-640.jpg"></a>

## MicroPeak Application ##

The MicroPeak application written in Java runs on
Windows, Mac OS X and Linux.  It captures and saves the flight data, then
produces plots and statistics. More information is available on the main
[MicroPeak](../MicroPeak/) page.

<img src="micropeak-graph.png"/>

## Developer View ##

Here's a close-up view of the hardware

 * Hardware Features
	* ROHM RPM-075PT Phototransistor
		* Peak sensitivity matches MicroPeak LED color
	* [ST Micro TSV521](http://www.st.com/internet/analog/product/251123.jsp) CMOS op-amp
		* Low power
	* [FTDI FT230](http://www.ftdichip.com/Products/ICs/FT230X.html) Serial to USB adapter
		* Drivers available for Linux, Mac OS X and Windows.

 * 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)

## [Upcoming MicroPeak USB version](future) ##

## [History of the MicroPeak USB interface](history) ##

<center><img src="../logos/micropeak-usb.svg" height="64"/>