phw (08/13/82)
I own an Atari 400, and have seen and used Atari 800's. Yes, the price difference is about $350 (of course at $250 for a 400, that's about twice the price (more)). The 400 and 800 are internally the same (except for the power supply, more on that later) and have the same bus. The external packaging is, of course, different and is the major reason for the price difference. The touch-sensitive keyboard on the 400 is not a major problem: you can learn to touch type on it in a few hours, and the peanut butter and jelly design makes it nice when you have people using it that don't bother with food, drinks, etc. The 400 has only one memory slot that is only accessible through the back (i.e., take out screws & remove back) since it was not really meant to be user-upgradeable. There is only one cartridge slot (NOT the same as a memory slot, by which I mean RAM), but this slot addresses the entire 16K of memory that the two slots of the 800 address. In other words, although there may be roms coming out of Atari for the right and left slots, they can (and may) produce a single rom for the 400 which will be functionally the same. A few words on "upgrading" a 400 to something near an 800: The single memory slot on the 400 accesses the entire bus on the back, so that the whole 64K addressing is available. Since 16K is taken up by the OS and memory mapped registers, that leaves 48K to play with. There are companies that sell 32K and 48K expansions for the 400 (and 800) that only need one slot. There is also at least one company that sells an expander box, in which the bus is connected to a box with 8 slots and a power supply, so that you can stick in x memory boards, y roms, z speech synthesizers, .... Some people say that to run 48K in an Atari 400, you must change the diodes in the diode bridge in the power supply to slightly larger ones; others have said this isn't necessary. The system automatically locks up if enough power isn't present. The keyboard is accessible from the inside (keyboard bus, rather). Atari took it upon themselves to create their own encoding system (non-ascii), but I've heard of at least one person that figured out the scheme and hooked up a $20 keyboard from a computer fair to his 400. (Those of you using TTY's with detachable keyboards know the advantage of having a lap-sized typing instrument. Those of you with sore necks because you were too cheap to buy a stand for your 400 or 800 and are still using the box as a typing table can also appreciate the advantages. I know...I fall into both categories!). An aside to people who own old Ataris -- you can get the new OS and the new graphics chip (referred to as the GTIA chip) from Atari (be prepared for a run-around) for $? and $20-$25 respectively and can install them yourselves. A friend of mine and I did it in an afternoon. (For instructions, drop me a line.) Don't feel like you need the new chip or OS, though, because the Ataris are very good machines with the old versions. If anyone has any questions about the Ataris, drop me a line. I have a copy of the schematics (Atari sells them) and have contacts here with some REAL Atari hackers (I am a pseudo-hacker). Pat Wood harpo!mhuxv!phw ihnss!mhuxv!phw