Showing all posts tagged raspberrypi:

Raspberry Pi Software Development with a Cross Compiler

So far I've been editing and compiling my programs on the raspberry pi itself, using a ssh terminal. This is fine for small programs, but for anything large, it's nice to have a full Desktop IDE. So here I describe how I set up Eclipse on my Ubuntu PC to cross compile apps for the Raspberry Pi. PrerequisitesEclipse (I'm using the older Luna release, but it should be the same for other releases) installed in your desktop PC with:C/C++ Development ToolsC/C++ GCC Cross Compiler SupportA Raspbe...

Adding the MCP23017 GPIO Expander to the Raspberry Pi

More learning on the Raspberry Pi ... this time I am adding a MCP23017 GPIO Expander. My earliest Pi is the original Model B with only 17-ish GPIO pins, so a GPIO expander is very handy. I chose the MCP23017 (http://ww1.microchip.com/downloads/en/devicedoc/21952b.pdf) GPIO expander as it: adds many (16) I/O channels that can be used as digital inputs or digital outputseasy to interface to as it uses i2c (up to 8 of them can be daisy chained bringing an additional 128 GPIO ports)it is relativ...

Connecting A 20x4 HD44780 LCD with YwRobot LCM1602 IIC V1 Piggyback I2C GPIO Expander to my Raspberry Pi

Next up on the Pi Project, connecting an alphanumeric LCD. Almost all alphanumeric LCDs on the market are driven by the Hitachi HD44780 or compatible chipset, regardless of their size. The HD44780 takes care of "drawing" the characters on the LCD display, based on commands it receives from a host microprocessor over a 10-pin I/O bus. The microprocessor is expected to communicate with the HD44780 by setting the individual I/O lines to high or low in the correct combination and sequence. Th...

Adding A Real-Time Clock to the Raspberry Pi

10 Jan 2015 As shipped, the Pi has no real-time clock, and depends on the internet to determine the current time. Since my Pi might run without internet, I added a real-time clock to it. It's an off-the-shelf DS3231 (http://goo.gl/BKyjT9) unit with removable battery that plugs directly into the pi's headers, tapping the i2c bus and 3.3V power and ground. To enable i2c on the Pi, so that it can read data from the RTC, you need to: run "sudo raspi-config"chose item "9 advanced options"choos...

Connecting to the Serial Port on a Raspberry Pi

The Raspberry Pi features a serial port which can be used to access serial devices, or as a remote terminal connection into the Pi. Unfortunately, the electrical characteristics of this port is at TTL levels, rather than the RS232 levels which a PC or most devices require. A converter can be used to adapt the TTL levels to RS232 levels. There are ICs that will do this for you such as the MAX3232. I bought a ready-made board (http://goo.gl/faOGpi) that incorporates just this IC. The board fit...