Embeded Design

So /prog/,
I wanna learn how to do embedded design, interfacing, and programming (sort of like how TI's are made, and old school non-complex computers such as the c64).

Any advice, information, etc. to point me in the right direction? I'd prefer to get input from people who have experience in this area. For example, I have an tiny display that works from a phone. Don't know how to use it, but want to take a cpu (I have a 8086 chip lying around), a ROM, and write the software to put a circle or something on the screen.

>>1
The microcontroller route is much easier to start with, microcontrollers are CPU with a few hundred registers instead of RAM, and tri-state pins with resistor pull-ups. Eventually you could interface the 8086 and RAM with it to make a ``real computer''.

You'll need to Google for a datasheet of either your tiny display as a module, or the driver IC to make use of it. You'll have to read the datasheet back-to-back sometimes because of the usually picky timing and contrast voltage levels involved, a volt difference and you can't see anything. Usually it will require negative voltage, and you'll need to come up with capacitor charge pumps across the clock line to generate -40V out of 4.5V or something.

It might just be simpler to either do blinking LEDs or better yet (for a home computer project), learn NTSC/EIA signals (ignore color and its not too hard, people have made TV pong with microcontrollers quite a few times, the PICs with 4 cycles per instruction usually gave something between 50 and 150 pixels of horizontal resolution). You'll need to hand craft PIC assembly for this performance though, and offload non bit pushing code to happen during the blanking timing periods, the Atari 2600 performed video generation from the game code in this fashion if I'm not mistaken.

After choosing what to display with, the real issue with showing something on the screen other than pong will be RAM. Raster operations on bitmaps in memory will be hard with a few hundred bytes of microcontroller register memory, you'll need RAM for general purpose graphics on a home computer project. There are other possible strategies to displaying something on the screen, for a text based display you could check out the September 1973 Radio-Electronics article on the TV typewriter (google) for inspiration.