View Full Version : Code Blue

December 20th, 2010, 12:21 PM
After a month or so of tinkering with my rainbow I'm finding the lack of support for any real DOS applications to be a bit of a downer. According to the wiki, there was a program called Code Blue that gave you proper PC emulation but I can't find any trace of it anymore. It is hiding in the smaller software channels or is it gone forever?
Also, I can't find any sources for the Rainbow optimized version of Windows 1. Well I guess I could care less about it for now but what about Code Blue? Does anyone know where it might still be found? I kinda want to use some DOS programs on the system but if Ic an't I will probably replace the whole system with a 5150.

December 20th, 2010, 01:27 PM
Took me about 30 seconds to locate it here (ftp://ftp.update.uu.se/pub/rainbow/msdos/cb/).

You could also drop Mark Graybill a note to see if he wants to distribute it. Believe it or not, Intersecting Concepts is still around.

December 21st, 2010, 11:42 AM
I have never heard of that FTP. Wow. It's nice.


Wow. It's really cool when you stumble over these old garage-based software developers that go right back to when it was actually being coded in the garage. They are so rare now. I'll have to inquire indeed and thank him for creating such a wonderful product.

December 22nd, 2010, 08:17 AM
Also, you can have a look here (a little self-promotion, sorry...):


I have Windows 1 and 3 for the Rainbow, but apparently I haven't added them to the archives yet. A word of warning, though: plain, old serial mice apparently do not work with Windows 1 on the Rainbow. You'll end up using the keyboard only until someone out there pipes up and explains what kind of mouse is expected.

As for DOS applications running on the 'bow, most early stuff that is text only should work. Anything with graphics or that operates in full-screen text modes won't work. Some full-screen text programs (WordPerfect 5.1 is a notable example) will run fine under Code Blue. It's more interesting, in my opinion, to mess with some of the Rainbow-native software.

December 22nd, 2010, 09:56 AM
Does that mean that even with the graphics option installed in a Rainbow, I still can't even get MDA emulation?
I heard somewhere that the serial port was somehow "different" to that of a usual DB25 serial port. I have yet to look into this but until then I got a serial Microsoft Mouse (it's really an InPort but it uses some sort of adapter to convert to serial) on hand.

Edit: Your archive on your website is also fantastic.

December 27th, 2010, 04:18 AM
I'm glad you like the website! It needs some work, but its functional and slightly incomplete.

I think you might have a big misconception about the Rainbow. It is not IBM-compatible at all, nor was it ever meant to be. The hardware is drastically different, and the graphics system is no exception. On the PC, and please excuse me if I'm wrong, the graphics memory is mapped to 640KB, hence the memory limit on PCs. The Rainbow graphics architecture is nothing like this. The graphics memory is not mapped to a main memory address at all. That's why MS-DOS on the 'bow has access to 896KB RAM, possibly more with a custom memory expansion card, without all the HIMEM/EMS/XMS nonsense necessary on IBM models. It does have text video memory mapped to a main memory address, but graphics memory is completely inaccessible via system memory addresses. Additionally, the text memory maps the screen using a non-trivial linked-list, meaning simply reading/writing to certain memory locations without extreme care will not result in a character being displayed.

The graphics RAM on the Rainbow is entirely separate from system RAM and can only be "accessed" via the graphic device controller (GDC). In order to display an image, for example, you would need to build the image in system RAM and then request a copy action by the GDC to pull the image into graphics RAM. The process is unpleasant and not particularly fast. On the other hand, the Rainbow's GDC is optimized for vector drawing, so passing it a list of points will result in quite fast shape drawing on the screen. Also, the Rainbow's graphics modes are 384x220 at 16 colors (from a palette of 4096) and 800x220 at 4 colors (from a palette of 4096), considerably higher than the IBM graphics cards at the time. If you have a color monitor, pictures of people will look considerably better on a Rainbow due to the large palette, allowing for more flesh-colored shades to be drawn compared to a fixed palette like CGA or EGA. However, graphics on the Rainbow tend to be slow as dirt because of the memory layout.

So long story short, no, the Rainbow cannot run any graphics programs designed for the PC. You could write an emulator to allow the Rainbow to do so, I suppose, but it would be unbearably slow and useless if it worked at all. Code Blue will only allow PC programs to run by emulating character video access (I believe) and some of the interrupts that differ from the Rainbow.

The Rainbow's serial port (not the printer port, which is actually just another serial port) is standard. The UART is not compatible with the PC, so communications programs for the PC won't generally work on the Rainbow. Programs that require a FOSSIL driver, popular with BBS software, will run fine with a Rainbow FOSSIL driver installed.

I've also tried Microsoft serial mice with the Rainbow with no success on Microsoft Windows 1. A serial mouse works fine under Windows 3. I don't believe that Windows 1 was ever "released" for the Rainbow, although it certainly exists. I've heard mentions that the DEC hockeypuck mice work with it via an adapter that plugged into the printer port, but that could be a rumor. There is so little information associated with Windows 1 on the Rainbow because it was never sold that I'm not sure a mouse will ever work with it.

December 27th, 2010, 11:49 PM
A DEC mouse works fine with Windows on the Rainbow. I had one with a native plug for parallel when I had one years ago. I only have standard DEC mice now, and no Rainbow.

Windows is ok under version 1, thought Windows 1 is limited. Windows 3 was a dog for me, I got rid of it. The Rainbow is a good system, but running it as a PC is missing the point, IMO. ;)