- Published: Saturday, 10 August 2013
- Written by Bitfogav
- Hits: 11086
Project by Gavin Wiggett.
I bring you the Matrix/Game Shield, (Red/Green 8x8 led matrix).
I started this Project just a few months ago (May 2013), the idea was to make a game system where you can design your own games for a 8x8 led matrix or even some cool animations, I have been into leds and led matrix displays for the last few years since the day I saw Brad Slattery 8x8 led The Great Race.
The concept was to make a shield that was compatible with Firewing and Arduino and to make a shield that used the least amount of I/O pins as possible. In this case the shield only uses 4 pins in total to control the red/green matrix and all 6 buttons, leaving the other I/O pins free and for use for other peripherals e.g. SD Card/Usart.
The matrix is controlled by using three 8-bit shift registers 74HC595 which are linked together, 1x for Anode, 1x for Red led’s and yes you guessed it 1x for Green led’s, there are also two ULN2803 power drivers to source the matrix led current (helps increasing led brightness). All this is controlled by only three I/O pins, the data is sent out to all three 74HC595 at once, and then latched into the 74HC595 registers. Loads more information can be found here for the 74HC595 shift registers: Arduino ShiftOut. An interactive 595 shift register simulator here can help you visualize the required sequence to shift data to a display.
The buttons are controlled by using only one analog input (ADC) channel, a resistor network is used to read from a series of buttons. The concept is explained in several articles on the Digit-DIY pages, including here: 10 Keys on One Port Pin?
To learn more, visit Firewing Game Shield on the Firewing website.
And check out Firewing Compiler