Fletchtronics

Peter Fleury's character LCD library is a handy library that works on a large number of 2 to 4 line character LCD models.

When shopping for LCDs you will recognize the type that will work immediately when looking at datasheets. These models all have the same 16 pin parallel interface (3 or 5 power pins, 8 data pins, RS, R/W, E). They all share the same instruction set and have a method for writing to both the screen (DDRAM) and writing pixels to the characters (CGRAM).

If you have a character LCD model that seems similar to the above description, it's very likely that this library will work.

Peter Fleury has an excellent collection of AVR software for some very common tasks. The next two posts contain knowledge gained as I learned how to use these libraries, including all the "gotchas" and complete descriptions of the code and circuitry. Hopefully this information will help get you started fast.

The first library we'll be looking at today is the i2cmaster TWI library. It is extremely useful for connecting to external TWI/I2C hardware quickly and painlessly.

Inside LUFA is a neat project called AVRISP. With this code, your BumbleB becomes a programmer for other AVRs. The project can be found in ./Projects/AVRISP. With a few changes we can use this code and BumbleB to program other AVRs and even other Bumble-Bs.

Bumble-B AVRISP -> ATMega168 Example

Fletchtronics is now offering the first in a series of Complete Solutions, a set of useful components and development boards.

Complete means centralized information. You won't have to search around the web for information about the component. All relevant links and immediately important information will be posted on the product page.

PCA9555 is a 16 bit general purpose serial IO expander from NXP Semiconductors. It speaks I2C/TWI. PCA9555 gives your application 16 more IO pins. Up to eight devices can share the same I2C bus. Therefore you can add up to 128 (16*8) additional outputs and/or inputs, using just two microcontroller pins to control them. This version is DIP-24/600 mil shape, perfect for breadboarding.