Games in progress for RC2014 with OLED screen.

he OLED screen that Quazar makes for the Z80-based RC2014 is 128 x 32 pixels, a wide and thin format. The way that you send data (bytes being vertical) makes it good for smooth sideways scrolling.

I did this a while ago and as usual I'd almost finished when I moved onto something else. It's written using Forth, which I really love. In return for a small sacrifice in performance (according to Leo Brodie's book, it can be almost as fast as assembly) you get some very helpful features. For example, numbers are 16-bit signed (in the implementation I use), the stack makes it very easy to pass parameters in and out when calling words, and I like the way it makes me structure a program. It forces you to start with the small building blocks.

So it is with some joy that I've returned to the dino game and started a new tunnel game.

Again the screen format is well-suited to this type of thing. For the Dino game I made myself a box with two arcade buttons (he jumps and ducks) and so I'm using the two-button-controller again. I'm using the i/o registers of the YM chip for input, so I may write my music driver in Forth and add sound/music to this game. it's a shame that it's hard to capture on camera the beauty of the OLED display.

With a single-pixel shift per frame it's moving silky-smoothly although at quite a pedestrian pace. I'll probably end up moving two pixels at a time.

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