User manual

LPCXpresso Experiment Kit - User’s Guide
Page 135
Copyright 2013 © Embedded Artists AB
8 Projects
This chapter contains a list of project ideas that build on the knowledge gained from the experiments in
the previous chapters. The projects involve a bigger programming effort than before and are real-world
in the sense that part of a real product application can very likely contain one of the project ideas. The
idea is to deepen your understanding of embedded systems and enhance your programming skills.
The projects are not described in detail like the experiments. Instead the descriptions are quite short
and are mainly supposed to give you some ideas and get you started. Solve the details on your own –
that is what programming is all about anyways! Alternatively create your own project based on these
ideas.
8.1 Interface a Color Sensor
Select a color sensor, for example one of these:
- http://www.sparkfun.com/products/10701 (with a digital interface)
- http://www.sparkfun.com/products/10904 (with an analog interface)
Create the hardware and software interface to the sensor. Output can be on the console, the RGB-
LED or on a display.
8.2 Interface a Real-time Clock (RTC)
Select an RTC chip and interface. Most commonly used interfaces to these chips are I2C or SPI. For
example NXP PCF8523 with I2C interface or PCF2123 with SPI interface.
Create an application that displays the real-time on a display or via the console. It shall be possible to
set the current time. If a display is used, create a small menu system controlled by the joystick push-
buttons or the rotary switch.
Implement alarm functionality.
Implement low-power operation where the processor sleep and only wake up once a second to update
the time, or even once a minute. The processor shall also wake up on alarms.
Several enhancements are possible to this project:
- Implement automatic adjustment of the clock once a day.
- Implement automatic adjustment for summer and winter time.
- If the RTC chip does not support leap year add support for leap year compensation.
8.3 Interface a GPS Module
Interface a GPS module. Most modules have a UART interface and communicate with the standard
NMEA protocol (use google to find more information about this protocol specification).
A simpler project just output the results from the GPS module on a display with X/Y-coordinates. A
more advanced project visualizes the location on a graphical display.
8.4 Interface an SD/MMC Memory Card
Interface an sd/mmc memory card via the spi bus. There are application notes from NXP that gives a
good start. Add FAT-file system handling “on top” of the low-level interface drivers.
8.5 Interface an Accelerometer and Gyro
Interface an accelerometer (2- or 3-axis) or a gyro. There are several chips with associated breakout
boards for simpler interfacing on the market. Select a chip with digital interface (I2C or SPI).