Matrix display thoughts
Matrix display thoughts
The LED matrix displays showed up in a week from China. Quicker than some UK suppliers manage!
I've been struggling with how to drive these and am not totally certain they will make it to the final project.
There are a number of MAX chips such as the Max7219 that can take a digital serial instruction from a microprocessor SPI output and translate it into a bitmap to display on the matrix. The great feature of these chips is that they actually flicker at very high frequency the LEDS, resulting in much lower power consumption. Ideally I want a prewritten class to use when driving these as I don't have the time to write my own unless I have to.
There is also a lesser known MAX chip available from Farnell for a very cheap price that can handle two of these matrix. However it is surface mount and looks really hard to prototype with. It may be best to stick with the DIL chips for this reason. The following link shows someone attempting a similar feat. However for what I have in mind I need to drive two of these independently. This is not mentioned, but it looks like there is a daisy chain output from the MAX chip to allow this. http://fabienroyer.wordpress.com/2011/03/13/using-a-max7219max7221-led-display-driver-with-a-netduino/
Was thinking about the matrix display - this is going to need some sort of smoked acrylic cover over it to make it look "nice". Been on the web trying to find something suitable. Not finding anything cheap I'm now looking a pound shops for suitable things I could cannibalise for this purpose...