sdb@tekecs.UUCP (Steven Den Beste) (09/20/83)
I own a TRS80 (Gad, how that "80" hurts) Color Computer, which is based on the 6809, not the Z-80. By and large I am very pleased with it, but I saw an article by someone saying he thought that people were feature-blind about their own systems, that every system had flaws, and that he was curious as to what they were. I thought I would tell what I know is wrong with the coco (and then maybe just a tad about what is right). I would be interested in similar articles from owners of other machines! 1. The standard keyboard sucks. As soon as they were available, I shelled out about $75 for a real keyboard. I understand that the new version of the coco has a different keyboard which is much improved, but it is still not as good as the one used by Commodore or other such people. 2. The screen is too small. At 16 lines by 32 characters, it is painful, though not as painful as the VIC-20. There are software packages available that correct this by putting more characters on the screen and using one of the graphics modes to do it. The most readable format I have seen is 24*51, though 32*64 works if you turn off the color control of your set. 3. The standard box does not have lower case display. Again, as soon as it was available, I shelled out about $75 for a lower-case mod which improved the display immeasurably. 4. You cannot put text and high-res graphics on the screen at once, without generating the characters yourself. There are software packages you can buy which will do this for you, even dividing the screen into windows - but it is still a pain. 5. THERE ISN'T ANY UART! There is a high/low sensor and a high/low generator, and you do the rest with software. For obvious reasons this is a real pain. 6. You cannot get more than 4 colors on the screen in any reasonable graphics resolution. Most people can creatively work around this, but one can still dream... 7. The disk operations are done by the processor - there isn't any DMA. Ordinarily this isn't a problem. Now, if you people don't get into the spirit of this thing, I can see all this backfiring really badly. Don't take this as an admission that the coco is a pile of junk - if I were asked to advise someone of which computer they wanted, and it fell into this price range, I would recommend the coco. Don't gloat too loudly or I will take some pot-shots at other processors (Hey, C64 users, why are your disks interfaced serially? Ain't that a little slow?). The coco has the 6809 in it, the most advanced and probably the last true 8 bit processor that will ever be designed. It is capable of running position-independent-code with about a 10% overhead in speed and code size. Because of this, it is possible to write a real timesharing and multi-tasking operating system for it - and one exists. It is called OS-9, and is going to come out in about two weeks. Reports have it that it is very UNIX-like, allows people to spawn background operations with the "&" operator, supports pipes, and will actually run two users (one on the keyboard, one out the RS-232 port). Of course everything comes to a screeching halt whenever anyone accesses the disk, but the disk isn't used for timesharing. It supports hierarchialized file structure and has lots of other nifty features. Frankly, I don't see how any such system could be implemented for any Z-80 or 6502 system without scads of bank-switched memory, and even then it wouldn't work very well. OS-9 will run on a stock 64K coco. Oh, did I mention that between OS-9 and FLEX, every major language is available for the coco - usually from more than one vendor? Ah, expiation is good for the soul... Steve Den Beste Tektronix