yeah. it's just that a mega was mentioned. and all that flash. then i realized how large the files actually were and that all that flash wasn't, in fact, all that much
It would plenty large enough to buffer the parts of the image I need on an ongoing basis. But, my goal, is still to stay within the boundaries of the 328 for now. I have very little physical space, so I'm trying to limit myself to an arduino mini form factor.
If you stored all possible clock digits, including background, on the SD, you would do your updates by writing a bitmap instead of writing text.
I'd actually considered that. Even at a large font size (say "6"), I'm at about 4K per digit. Assuming I don't use seconds on the clock, there are 28 possible bg/digit combinations... so about 112K of extra data.
One of my ideas was to have enough bg images in the card to display a new one every day of the year, perhaps. Now that ada has broken down the format of the bitmap file in the example sketch, I don't think it would take too much effort to read in a new bg image every night at midnight... and, if the digit files aren't there, I could create them on-the-fly. Might take a couple of minutes to do them all, but I'd only have to do it once a day at a maximum.