Well, we have not done much on this thread lately, so I thought I'd update it. I got a chance to work with some LCDs driven by an Arduino microcontroller today. After about 1 hour of work, I came up with this:
So far, it's static... meaning there is no changing of the display.
But there are a couple of interesting things.
First, if you use a parallel connected display, about 80% of the available I/O pins are dedicated to the display. Some displays also do not have any on-board memory, so the microcontroller has to provide it. This means that about 80% of the resources of the microcontroller are used just for the display.
But I am using a serial display, which has it's own memory, and only takes a single pin. However, you have to put in delays and change the baud rates or the display will write slower than the microcontroller sending data and will otherwise be garbled up. There is no bona-fide flow control to the display, so you have to throttle down the microcontroller so the display can keep up.
This sort of complicates things a bit, but far better than eating up the resources with a parallel display.
Anyway, this is not a final display design by any means. But it is a cool first attempt.
I can probably get more bar-graphs on the display if I run them horizontally rather than vertically. Unfortunately, you cannot make the fonts any smaller which means the text takes up a lot of space. Perhaps I can come up with some symbols for the various tanks...
I could use a flame graphic for LP, a water droplet for the fresh water tank, a toilet for the black tank, and I am not sure what to use for the grey tank.
Thor Forums
