***›       Atari 8-Bit Computers›    Frequently Asked Questions List›    on the INTERNET-Revised 28-Oct-95› (This info was sent to me by TOM SMITH› an OHAUG member. THANKS TOM!)› (Ed. I have tried to give you a  small› taste  of  the INTERNET info avalable,› through this article. I  have  had  to› format it to fit th newletter. A.P.)› › Additions/suggestions/comments/correct› ons are needed!  Please send to:› URL:mailto:mcurrent@carleton.edu› UUCP:› ...!umn-cs!ccnfld!mcurrent› Cleveland Free-Net: aa700›› Copyright  (c) 1992-1995 by Michael D.› Current, and others where noted.  This› file may be reproduced, in whole or in› part, so long as the content  of  that› portion  reproduced  is  not modified,› and so long as credit is given to this› FAQ  list  or  its  Maintainer, or the› author of that section reproduced when› given.›› The  Atari  8-Bit Computers Frequently› Asked Questions List  was  created  to› provide answers to many commonly asked› questions   found  in  the  Internet's› comp.sys.atari.8bit/Info-Atari8› Digest/INFO-A8  discussion  group.  It› is in a constant state of development,› and  comes with no guarantees.  If you› see any problems, I need to hear  from› you!››    Where  to  get  the  latest copy of› the  8-bit Atari FAQ List  ---› The home of many  FTP  archive  sites,› automatically updated monthly: › URL:ftp://rtfm.mit.edu/pub/usenet-by-› group/news.answers/atari-8-bit/faq›› The  World Wide Web hypertext version,› automatically generated monthly:› URL:http://www.smartpages.com/faqs/› atari-8-bit/faq/faq.html› URL:http://www.cis.ohio-› state.edu/hypertext/faq/usenet/atari-› 8-bit/faq/faq.html›› WWW "flat hypertext" versions,› automatically generated monthly:› URL:http://www.cs.ruu.nl/wais/html/na-›› dir/atari-8-bit/faq.html› URL:http://www.lib.ox.ac.uk/internet/› news/faq/archive/atari-8-bit.faq.html›› Usenet newsgroups where this FAQ  list› is automatically posted monthly:› URL:news:comp.sys.atari.8bit› URL:news:comp.answers› URL:news:news.answers›› You can also get the latest version by› e-mail.› URL:mailto:mail-server@rtfm.mit.edu ,› message says:  send› usenet/news.answers/atari-8-bit/faq› quit›› Finally, you can always ask me  for  a› copy at›  URL:mailto:mcurrent@carleton.edu›› ------------------------------›› Subject: 0.1) Table of contents››  0.1) Table of contents››      Introduction›  1.1)   What   is   an   Atari   8-bit› computer?››      Usenet›  2.1) What is comp.sys.atari.8bit?›  2.2) What is comp.sys.atari.announce?›  2.3) What is  comp.sys.atari.advocacy›  2.4) What is›  comp.sys.atari.programmer›  2.5) What is comp.emulators.misc?›  2.6) What is›  comp.emulators.announce?››      E-Mail›  3.1) What is the Info-Atari8 Digest?›  3.2) What is INFO-A8?›  3.3) How  can  I retrieve files from› FTP sites by e-mail?›  3.4) How can I post to Usenet›  newsgroups by e-mail?›  3.5) How can I access the World Wide›  Web by e-mail?››      Software Archives›  4.1) What is the University of›  Michigan Archive?›  4.2) What is the Boston Archive?›  4.3) What is the PVV Archive?›  4.4) What is the ClarkNet Archive?›  4.5) What is the  Gatekeeper's› Archive?›  4.6) What is the QACE Archive?››      Telnet›  5.1) What is the Cleveland Free-Net›  Atari SIG?›  5.2) What is the Youngstown Free-Net›  Atari SIG?›  5.3) What is the National Capital›  Free-Net Atari Users SIG?›  5.4) What is the Victoria Free-Net›  Atari Computer Users SIG?›  5.5) What is the Closer To Home BBS?›  5.6) How can I access the World Wide›  Web by Telnet?››      World Wide Web›  7.1) What WWW pages  support  the  8-› bit Atari?››      IRC›  7.9) What IRC channels discuss the›  8-bit Atari?››      Online Magazines›  8.1) What is the CAIN Newsletter?››      File Formats›  9.1) What's this UUEncoding stuff›  (.uu, .uue files) all about?›  9.2) What is an .arc file?›  9.3) Okay, how about a .dcm file?›  9.4) What is an .xmo file?››      Emulation›  10.1)  What  8-bit  Atari   emulators› exist   for other computing platforms?››      File Transfer Solutions›  11.1) What are the best terminal›  emulators available?›  11.2) Can I read/write 8-bit Atari›  disks on an IBM-PC?›  11.3)  Can  I read/write MS-DOS disks› on an 8-bit Atari?›  11.4) How do  I transfer files  using› a null modem cable?››      Storage Media›  12.1) What 5.25" floppy disk drives›  are available?›  12.2)  How  can  I  use  3.5"  floppy› disks with my 8-bit Atari?›  12.3)  What  do  I  need to connect a› hard drive to my 8-bit Atari?›  12.4) How can I use an IBM-PC as a›  storage device for my Atari?››      General Interest›  13.1) What's the best DOS for the› Atari?›  13.2) What hardware has Atari created› in the 8-bit computer line?›  13.3) What are the power-supply› requirements for my Atari  components?›  13.4) What are the pinouts for the ?›  13.5) What BBS software can  be  used› on the Atari?›  13.6)  What version of Atari BASIC do› I have?›  13.7)  What  are  the  Standards  for› Used 8-Bit Stuff?››      Other Documents of Interest›  14.1) What vendors, developers, or›  publishers support the 8-bit Atari?›  14.2)  Where  is  my  nearest   8-bit› Atari BBS?›  14.3)  Where  is  my  nearest   8-bit› Atari user group?›  14.4)  How  do  I  use  my   new   or› emulated Atari?›  14.5) What prominent Atarians are›  reachable by e-mail?›› ------------------------------››  Subject: 1.1) What is an Atari 8-bit›  computer?›› In  order  of their release, the Atari› 8-bit computers include the 400,  800,› 1200XL, 600XL, 800XL, 65XE, 130XE, and› the   XE  Game  System.   The  400/800› models were first  shown  publicly  in› November 1978 and first sold in 1979. › The final machine, the XE Game System,› was  released  in  1987.  Atari  Corp.› officially   dropped   all   remaining› support of their 8-bit  computer  line› on January 1, 1992.›› The  following  text  was  written  by› Chris  Crawford  and  appears in De Re› Atari   (Atari#APX-90008),   a    book› published  and  copyright  by   Atari,› Inc.,  1981-1982.   It  has  been very› slightly     modified     here     for› generality.››      "The internal layout of the Atari› 8-bit computer is very different  from› other  systems.   It  of  course has a› microprocessor (a 6502), RAM, ROM, and› a  (PIA).   However, it also has three› special-purpose (LSI) chips  known  as› ANTIC,  GTIA,  and POKEY.  These chips› were   designed   by  Atari  engineers› primarily to take much of  the  burden› of  housekeeping  off  of  the   6502,› thereby    freeing    the    6502   to› concentrate  on  computations.   While› they were at it, they designed a great› deal  of  power into these chips. Each› of these chips is almost  as  big  (in› terms  of  silicon area) as a 6502, so› the three of them together  provide  a› tremendous amount of power.  Mastering› the Atari 8-bit computers is primarily› a  matter  of  mastering  these  three› chips.››       ANTIC    is   a   microprocessor› dedicated to the television  display. › It is a true microprocessor; it has an› instruction set, a program (called the› display  list), and data.  The display› list and the display data are  written› into RAM by the 6502.  ANTIC retrieves› this information from RAM using direct› memory access (DMA).  It processes the› higher   level   instructions  in  the› display   list  and  translates  these› instructions into a  real-time  stream› of simple instructions to GTIA.››      GTIA  is  a  television interface› chip.  ANTIC directly controls most of› GTIA's operations, but the 6502 can be› programmed to  intercede  and  control› some or all of GTIA's functions.  GTIA› converts  the  digital  commands  from› ANTIC (or the 6502)  into  the  signal› that  goes  to  the  television.  GTIA› also adds some  factors  of  its  own,› such  as  color  values, player-missle› graphics, and collision detection.››      POKEY is a  digital  input/output› (I/O) chip.  It handles such disparate› tasks as the  serial  I/O  bus,  audio› generation,  keyboard scan, and random› number generation.  It also  digitizes› the  resistive   paddle   inputs   and› controls  maskable   interrupt   (IRQ)› requests from peripherals.››      All  four  of  these  LSI   chips› function    simultaneously.    Careful› separation of their functions  in  the› design  phase  has minimized conflicts› between the chips.  The only  hardware› level  conflict  between any two chips› in the system occurs when ANTIC  needs› to  use  the address and data buses to› fetch its display information.  To  do› this,  it  halts  the  6502  and takes› control of the buses."››      The  130XE  and  XEGS  contain  a› small additional LSI called FREDDIE, a› RAM address multiplexor.  According to› URL:mailto:sup8pdct@closer.brisnet.org› au (James Bradford), "Freddy is a type› of  memory  controller.   It takes the› address and clock  from  the  CPU  and› multiplexes  it  with  the appropriate› timings and  signals  to  use  DYNAMIC› memory.   Freddy  also   buffers   the› system  clock  crystal  and divides it› down then feeds  that  to  GTIA.   The› XEGS  has a freddy but it doesn't have› the extended RAM.  Even if it did, you› would  still  need  the chip that does› the REAL  bank  switching.   It  is  a› small    16-pin    chip    (Atari/Best› Electronics  catalog  number  CO25953:› rev9/page  42).   It  gets  RAS   from› freddy, the bank select bits from PIA,› A14, A15 and the 6502 halt  signal  to› control which bank of 8 chips RAS goes› to.  A14 and A15 then go to freddy for› the  address range of the extra memory› bank (or normal address range with  no› bank   switching).    The   ANTIC/6502› select bits in  combination  with  the› 6502  halt line, control the switching› of the PIA bank number bits to A14/A15› and which bank of memory RAS goes to. › Why people say freddy  does  the  bank› switching  is beyond me.  An 800XL can› look like a  130XE  with  that  16-pin› chip  installed   (That's   right   NO› freddy) and an extra 8 RAM chips."››      Beginners  at  using  the   8-bit› Atari platform may wish to contact›  Bill Kendrick,› URL:mailto:kendrick@sonoma.edu,    for› his Newbie/Emulator FAQ.›› The  following  is  taken  from Bill's› Newbie/Emulator FAQ.› Graphics:›   The Atari has maximum resolution  of› 320  x  192 (standard, non-overscanned› screen) x 2 colors.›   160 x 192 x 4, 160 x 192 x 2, 160 x› 96 x 4, ›   160 x 96 x 2, 80 x 48 x 4, 80  x  48› x› 2, 40 x 48 x 4 graphics are also› supported.›   40 x 24 x 256-character (128 normal,› 128     inverse,     character     set› indirection available)  text  mode  is› standard (2 colors).›   40   x   24   x   128-multi-colored-› character  (4  colors  per   character› allowed, the other 128 characters have› 4th changed into a color 5) and›    40   x   12   x  128-multi-colored-› character screen modes are available.›   GTIA graphics support 80 x 192 x  16› shade-only,  80  x  192 x 16 hue-only,› and 80 x 192 x 9 color screen modes.› Graphics Modes Summarized:› Mode  Horiz.xVert.xColorstext/graphics› 0›   40 x 24 x 2 text›   1    20 x 24 x 5 text›   2    20 x 12 x 5 text›   3    40 x 24 x 4 graphics›   4    80 x 48 x 2 graphics›   5    80 x 48 x 4 graphics›   6   160 x 96 x 2 graphics›   7   160 x 96 x 4 graphics›   8   320 x 192 x 2 graphics›   9    80 x 192 x 16 luminence-only› graphics›   10    80 x 192 x 9 graphics›    11      80  x  192  x  16  hue-only› graphics›   12    40 x 24 x 4-colored text›   13    40 x 12 x 4-colored text›   14   160 x 192 x 2 graphics›   15   160 x 192 x 4 graphics›   Normal (bordered), narrow› (underscanned), and wide (overscanned)› screen modes are available.›   Screen modes can be mixed (by lines)› down the screen using the Display List› (a  program  which  is executed by the› ANTIC   graphics   chip  every  screen› refresh (60 times per second  on  real› NTSC Ataris).›   Fine  scrolling  (both  vertical and› horizontal) can be enabled on any line› on the screen.›   All  other screen attributes (color,› player/missile   horizontal  position,› screen width, player/missile/playfield› priority,  etc.) can be ajusted at any› point down the screen via  a  "Display› List Interrupt."›   Four  8-bit  wide,  128  or 256 byte› high single color players, and four 2-› bit  wide, 128 or 256 byte high single› color missiles are available.›   A mode to  combine  the  4  missiles› into  a  5th 8-bit wide player is also› available, as is a mode to XOR  colors› or  blacken  out  colors  when players› overlap (good for making three  colors› out  of  two  players!)   Players  and› missiles  have adjustable priority and› collision detection.›   Sound:›    Four   voices   of   8-bit   pitch-› resolution,  4-bit  volume-resolution,› 8-distortion sound can be produced.  2› voices (1 and 2, and/or 3 and  4)  can› be  combined  to  make  16-bit  pitch-› resolution.   Also  4-bit  volume-only› modes  can  be  enabled  for digitally› sampled sound replay.›   A fifth "voice" is produced  by  the› internal  speaker  on  Atari 400/800's› (for keyclick and buzzer) and  in  the› XL's  and XE's this was (fortunately!)› rerouted   through  the  normal  audio› output,   and   the  keyclick  can  be› disabled.›   › (Ed.  Go  on  the  INTERNET  to  learn› more!›                -- end --›