FS1 for Exidy Sorcerer

[ClausB]

Someone ported subLOGIC's T80-FS1 to the Sorcerer but left the display as 16 lines, squashed in the lower half of the screen. I modified that port to use the full 30 lines on the Sorcerer. Two side benefits are corrected aspect ratio and double vertical resolution. No code was changed, just constants and screen pointers, a testament to how well it was written in the day.

Before and after:

 

[ClausB]

Here is the binary. Size 3C00, load and go addresses 0100.

 

[ClausB]

The manual is here:
https://archive.org/details...
Some of the key commands have been moved to the keypad:
Keypad controls:
2 pitch up
8 pitch down
4 roll left
6 roll right
5 roll neutral
9 throttle up
7 throttle down
- gear up
÷ gear down
+ radar view
* forward view
= drop bomb

 

[jltursan]

Impressive work, thanks!

How big is the map drawing area right now (in chars or logical "pixels")?

 

[ClausB]

It's now 100 by 84 pixels, or 50 by 28 characters.

Here's a new version with a little logo I drew:

 

[jltursan]

Haha, way cool the logo!. Is your machine overclocked?

 

[ClausB]

Thanks. No. The original port uses half the redefinable characters for the block graphics, so the other half is free for the logo. It's static and so doesn't take extra cycles.

 

[jltursan]

About the overclocking, I wasn't thinking in the logo (as you say, just a bunch of static chars printed in screen); but the simulator perfomance. I haven't seen it in action and 2 Mhz seems to be a bit low to get "fluid" updates...just my two cents...

 

[Eudimorphodon]

About the overclocking, I wasn't thinking in the logo (as you say, just a bunch of static chars printed in screen); but the simulator perfomance. I haven't seen it in action and 2 Mhz seems to be a bit low to get "fluid" updates...just my two cents...

I've never played the Exidy version but the TRS-80 version, which I assume is mostly identical, works "fine" at 1.77mhz. I guess this is almost doubling the vertical height compared to that, but considering the nature of the graphics I doubt that part alone makes much difference.

(FWIW, I vaguely recall the performance of the Apple II version being pretty comparable to the TRS-80 one even though updating the screen in theory took about 4x more effort as measured by pixels, or still more than twice the Exidy? Maybe in some very rare circumstances a 1mhz 6502 can be 8x faster than a 2mhz Z-80, but I would suspect it's more a measure of poking the actual screen updates into video RAM wasn't a huge share of the work it was doing.)

 

[ClausB]

You might think at first that doubling the vertical resolution would halve the performance, but think of this: horizontal lines have no more pixels so they draw just as fast. The more vertical a line, the more added pixels, so it averages to roughly 1.5 times as many pixels to plot.

I couldn't leave it alone so I improved the logo:

 

[ClausB]

The more vertical a line, the more added pixels, so it averages to roughly 1.5 times as many pixels to plot.

Not quite right. Lines up to 45 degrees have no more pixels. It averages to 1.26 times as many. And the Sorcerer clock is about 1.2 times that of the TRS-80, so it's almost a wash.

 

[ClausB]

I've added a horizon line. This was lacking, IMO. The manual says you can easily lose sight of the scenery and you should then fly on instruments. Well, a primary instrument for blind flying is the artificial horizon. FS2 has one in its panel, but FS1 does not, so I added a horizon line to the outside view. It borrows 2 lines from the civilian airport and moves them up in front of the aircraft, so it's only available in the wide scenery mode (- key).