TTL POV globe redesign (part 1)

Back in college I built a POV globe.  I was really not happy with it, mostly because it’s something I felt could be done with discrete hardware more easily.  The first part to getting the POV globe in chips is to work out how to store the lines and retrieve them.

The big plan includes using a bigger chip with bank switching for animations and maybe even higher bank switching for going between animations.  This means that we need X address lines for 2^X lines, Y address lines for 2^Y frames, and Z addresses for 2^Z animations.  Eventually I would like to have a dynamic clock divider so we can have a variable speed motor and still scale the line frequency to keep the image all displayed in one revolution.  For now I have put together a clock out of a 555 timer, and decoders for the 28C64 EEPROM made from 74LS161 chips.  The EEPROM was programmed using the TL866 programmer to a sequential pattern as an example.  You can see that this chunk of the circuit iterates through the addresses and the outputs are tied to LEDs.

<video showing reset circuit>

<video showing addresses counting up>

<video showing changing the clock speed changing (blink pattern in the chip)>

Next time maybe I’ll have a dynamic clock divider circuit.

here is the code.

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