Coin-Op Collection Presents: Smash T.V. (Alpha)

Midway Y-Unit Alpha Version for MiSTer Release:

As promised in my previous post and video, I am releasing an alpha version of the Midway Y Unit core for MiSTer. I don’t normally like to release incomplete work, but I thought I would in this case since I spent about 6 months playing around with various memory models and could not get past the inherent limitations of the MiSTer no matter what I did. What is released today is the best I think it is going to get, and to complete the work I need more resources which I would only be able to get on MARS.

There are a couple of notes to follow:

The CPU is running in uncapped mode. I programmed in a recovery mode, but the cycles to fetch data for the program rom are quite a lot so the recovery mode can never really catch up properly. It is generally good, but sometimes there are unknown glitches. These glitches don’t happen in the uncapped mode, so I am leaving it at that.

You will need Dual RAM to run this. Half of the program rom is on SDRAM 1 and the other half is on SDRAM 2. I split the requests among both sdram modules to enhance throughput and speed. Secondly, the same is true for graphics, I split it between both SDRAM slots to enhance throughput and increase stability. putting it on one SDRAM makes things unstable, and eventually things crash when there are a lot of things on screen. Extended Bitmap/ Palette RAM is also split.

All the games in the Y unit series will boot, however, only SmashTV and Total Carnage are playable. The reason is because these games did not use any “staging” space for Video RAM. They just used the amount of the framebuffer and rendered pixels directly – and as you know from my previous video, that’s about all the BRAM I can afford on MiSTer.

The other games use the staging space for FMVs or other high graphics. The 4bpp games don’t work properly at this time because I haven’t investigated a decoder for 4bpp graphics. If I do, those games likely will work on the MiSTer; Trog and Strike Force. If those end up working out, I will release another build.

This is an older, stable build of the core from early December. Some or many of the issues you may experience I have probably already investigated and fixed, unless it is memory related.

Happy New Year!!!

- pram0d