While this is a nice-looking sum especially for students (one month salary of a worker here), we have made clues only for a small portion of the work - how to display.
But there is much more work to do. Requires certainly teamwork - and the Rs15k will split among them, at least 4-5 people... Not too much left for us :-)

The work is:
- design, build and debug the HW (basically a '51 with or without memories depending on , and either a dual-DAC, or two single DACs, or a single DAC and a dual S/H, a cheap DAC can be a R-2R ladder (4 bits are enough)(but has to be strongly driven, not from open collectors), with an output buffer with adjustable offset and full-scale amplitude. I would build it on a protoboard, not bothering with a real PCB. Oh yes, and 3 wires (coaxs) to the scope :-). Also some power supply - maybe a battery?
- write/debug the "display routine". As a start, I would try just to change the voltaxes: Xmin,Ymin-Xmax,Ymin-Xmax,Ymax-Xmin,Ymax round and round and try to produce a nice square on the screen. Then proceed to displaying a set of lines, depending on an array of (X,Y) couples in RAM.
- design the "input device" - what about a joystick (switch type, not analog)? = 4 direction switches + one "fire" switch; maybe also a "horizontal line/vertical line" switch; perhaps also a switch for "start game" and/or "give up/restart" as a deluxe version :-)
- write/debug the routine for the "input device" applying debouncing; autorepeat for deluxe
- write the game loop, moving a "cursor" with the joystick and "placing" it when fire is pressed
- design and implement the strategy for the machine
- for deluxe version, display also score for both players, perhaps display hints for decreased point value etc.


Jan Waclawek



PS. While somebody might find this unfair helping students in a competition/with homework, I don't think so. Searching on the net and asking (cleverly) for help (and perhaps be persistent) IS a thing to learn today.