Hi guys, I am really excited to find out about the enterprise conversion of my game! I have to say I am really impressed with all that work and how you handled the next specific stuff (Z80N, dma, DAC etc). I recently acquired an enterprise 128 with the sd interface, so I will download the game and give it a go! But still, very impressive!
Hello lpotamianos, welcome in the forum
I do not know if you saw my answer on youtube
Thank you very much for the great game, and for the great music choice. Z80N instructions have been changed to normal Z80 instruction combinations There is no DMA, the game loads music (if the machine has more than 256KB memory) to the memory, and plays that what could be loaded, play back full music need 2,5 MB memory, DAVE chip's 6 bit DAC is used for digi playback, and 11KHz interrupt. Normally the game is not slower (what i experienced, 1st car goes over the map 14 sec slower than on Next but i think there is 60Hz video interrupt), the horizontal movement is not so smooth, because the horizontal resolution is half, there are some slow downs on a 4MHz CPU after 30rd wave, and always after wave 50, on 8MHz CPU the situation is much better, some slow downs after wave 50.
"Sprites" are drawn in each frame, i tried to do it as fast as possible, i am sure it could be a bit faster, towers are drawn only in case they are changed, shot sprite size decreased from height 16 to 2, and for speed reason 10-10 ground sprite phases are stored (i wanted to avoid horizontal morrirong, because it would be a bit slower than the vertical) , there is also a memory saving solution for air units, only Helicopter sprites have 4 definitions for the 2 phases, phase 1 in X+0 position, and X+1, and phase 2 in X+0 and X+1, others have phase 1 in X+0 and phase 2 in X+1 that's why their flashing is slow, because their phase changes only when they moved 1 pixel.
If you are interested about the source what was made from disassembly , i can send it to you
