Amiga - Description of the AMIGA 500/2000 - Amiga from within: a keyboard, drives, I / O Connectors. What else can you connect?

         DESCRIPTION OF THE AMIGA 500/2000.


        The heart of the computer is a 16-bit Motorola 68000 
processor with operating frequency of 7.2 MHz. The processor 
has a memory of RAM (memory) 512K and supervises the work of 
four specialized BIS: GARY, PAULA, FAT AGNUS, DENISE.



        FAT AGNUS (fatty Agnus), so named because it is a chip 
with 84-pin in a square enclosure. It controls 25 channels of 
data, including disk operations and sound, while minimizing 
interference with the CPU. Except It can also easily transfer 
blocks data in memory without CPU

that allows rapid formation of
image.


         DENISE responsible for the schedule.
It generates images with different
resolution - from 320 x 200
points up to 640 x 400 pixels, has 4,096
hues, controls 8 sprites and
displays the text on the screen, summarized in 60 or
80 columns. Number of colors on
the screen is only limited possibilities of RAM. usually 32 (5 
bits / pixel) at resolution of 320 x 200, 16 or

4 at 640 x 200 and 2 for the resolution of 640 x 400 pixels.


        PAULA controls the sound. She
has 4 votes with a range of nine octaves each, configured in 2 
channel stereo. It uses the amplitude and frequency modulation. 
This allows the Amiga computer to imitate any sound - from the 
noise of the car Ferrari, before the vote, Sabrina. In 
addition, PAULA controls the drive and I / O ports.



        GARRY performs less noticeable
function - to control the data bus, organizes the data for the 
central processor and control some functions of the drive. 


        With the outside world Amiga computer
connects the interface CENTRONIX, RS-232, a monitor, keyboard 
and mouse. Amiga can be connected to virtually any monitor. 
Recommended branded monitors 1082, 1084. Model 1084 - is more 
versatile - it has inputs TTL RGB (digital) and analog RGG, and 
Composite Video for the Commodore-64 or the VCR. The latest 
model 1084S - stereo. 


        The layout of the keyboard like a keyboard, IBM AT, in 
her 95 keys (depending on the scheme) and the keyboard works 
flawlessly. It has a handy profile. However, the mechanics of 
AT keyboard is more convenient to work with. 


        For Amiga computers is available
many additional peripheral
devices: an additional drive to floppy disks 5.25 "(inch) or 
3.5" (inch), hard drive, color printer, modem, real-time clock 
with an additional memory, RAM, and battery-powered, MIDI,

transducers of sound and image, and
as CD-ROM (A570), allowing use as a music and discs
Amiga and IBM. The action of the converter
Image is of special interest
as the Amiga can work with pictures from a VCR or camcorder
real-time.


        Includes PC Computer
Amiga, there are three floppies: "Workbench",
"Amiga Extras", "The Very First". "The
Very First "- a proprietary demo
(Training) program for "only just beginning." The program 
demonstrates the rules work with a floppy drive, floppy and 
mouse. 


        "Workbench" - a system diskette.
It is a set of signs for the chip PAULA, data on the system 
configuration and programs that make it

installation program to service a modem and more than a dozen 
popular (driver on the computer jargon), clock, calculator, 
notepad, program for editing icons, synthesizer

speech, and also for those who do not like the icons and mouse 
- CLI (Command line interface), allows you to interact

with a computer in the traditional way, then
is using the keyboard.


         Watches - usually analog or, if
switching, digital, very satisfied
interesting. The very image of the dial
arrows made in the form of vectors. Can
arbitrarily change the window size, while
face fills the screen.
An interesting feature clock - wake up -,
it is processed only once, and it's easy
mask, closing or hiding a window with
hours. Alarm should record the last data is processed and 
finally to Stop the program. This is the most

effective way to tear a man
from your computer!


        The calculator has all the usual features, and notebook 
- this is rather a program to print beautiful texts than indeed 
notebook. It offers more than a dozen fonts with different 
matrices (From 8x8 to 20x20 pixels). Each font can be in 
italic, underline, or bold, to the same fonts can be derived to 
the printer. The very process of starting the program lasts 
about a minute, and the program requires a certain amount of 
memory. 


        Program for editing icons
allows you to design your character, but
it takes a long time, since there is no
graphics functions, such as drawing
lines, circles, and the like.


        CLI except the duplication of functions,
achievable by operating icons, such as formatting a disk,
change of name, copy the file
gives access to other application procedures. First of all, 
it's "Disk Doctor" - program "repair" floppy disk, allowing

edit the file starting sequence of commands (startup - 
seqence), which performs computer after downloading DOS.



        The third disk - "Amiga Extras"
Amiga Basic and contains several application programs.


        Amiga Basic is not something
unusual, despite the fact that there is a lot of the 
maintenance functions of graphics and sound, including a speech 
synthesizer. However, the editor, that is, the part which runs 
a regular user, does not work very quickly and does not provide 
comfort of use. BASIC itself is very different from the 
standard for smaller computers, such as Atari 800 XL toward the 
expansion of functions. The program allows for structural

programming, it does not need numbering
lines. It can define your own
procedures and so on.


        Under "Tools" (instrument) -
more interesting things. There are:
MICRO EMACE - full-screen editor
lines; FED - editor of signs; KEY TOY -
tip location of the keys (it is useful
in the case when we redefined the keyboard, such as a keyboard 
Dvoraka and want to return to the normal configuration); PRINT 
FILES - Print program file; IKON MERGE - a program combining 
two images so that the choice of the tool instead of outputting 
selected image is displayed another image (you can get the 
effect "Pushing a drawer"). Program MORE

- Displays the contents of any file; FREE MAP - the amount of 
free space of RAM, a PM with a funny picture

bunny demonstrates one of interesneshih
capabilities of the operating system - running multiple 
programs simultaneously (Multitaksing).



        This program shows a graph
Employment RAM and processor power of employment over time. 
Only this chart shows how life is good chip Motorola on a 
computer Amiga. Running while the music program (Sound

studio), a program of partition DEMOS, watches,
PM will not be able to load the processor so that it operates 
at full capacity more than a second. My experiences have ended 
hang the processor, not enough memory. 


      Amiga 500 belongs to a class of home computers. This 
means that you can use it to write texts, send the data to play 
with the transformation of sound or image. And if you want to 
hunt and for harmful space aliens.



              AMIGA INSIDE


                  DENISE

                 ********


        The main function of this scheme is to generate a 
graphical signal. Part of this work previously carried out a 
scheme AGNUS, which takes the image data and sends them to 
DENISE in parallel code. DENISE converts these data to the 
serial image signal. This also applies to graphics "hell". In 
addition, properly defined priorities graphic details (such as 
"devils" may be under the plan and the first graphic on the 
second), and the priority of colors (eg, mode, HAM, ie 4,096 
shades of color simultaneously, or in the Extra

Half-Brite, which you can get a 64
color from the basic palette 32 colors).
DENISE also detects mismatch
"Little animals" and the background and the "little animals" 
among themselves. 


        This chip vyponyaet another
function is not associated with the graphics - keeps track of 
movement of the mouse and joystick. WARNING! JOYSTICK not be 
connected to a computer works. This can damage DENISE. DENISE 
digital inputs are protected some extent, but the owners

Commodore-64 can you enlighten than ends switch joystick while 
the computer. 


                  PAULA

                *********


        PAULA is the second major computer chip Amiga. It serves
All transactions relating to disk drives, serial RS-232, music 
and analog inputs. In addition, PAULA controls all interrupts.



        Now about the sound capabilities
PC Amiga. It has 4 independent 8-bit analog-digital converters 
that operate in the stereo. That is a simplified version of the 
CD player. The sound in the computer Amiga is not generated as 
the Atari ST, or Commodore 64, and is written in the form of 
figures -128 to +127. Negative values

numbers correspond to the proportional retraction cone 
loudspeaker, and positive values - his expulsion from the 
magnet gap. This makes it possible reproduce any sound, as in 
the presence of a channel DMA. This means that programmer 
enters in the register early audio data (samples) and frequency 
of play. That's enough, for example, Playing the first 
Beethoven's Fifth Symphony. Unfortunately, to play the entire 
symphony to a few tens or even hundreds of megabytes of memory, 
especially when important for you to sound quality. The main

system (A500 with 512 kB CHIP-RAM),
after the introduction of a good program for audio processing, 
is about 270 kB of free memory. This is sufficient to record 
works of lasting 13 seconds with good audio quality (bandwidth

to 20 kHz) and 27 seconds at an average (band
frequencies to 10 kHz). When a telephone
communication bandwidth of up to 8 kHz, received 33
second, but a fan of Beethoven's best
If hate computer for profanity classics.


           CHIPS CIA (8520)

          **********************


    IC CIA (Complex Interface
Adapter) is called the CIA-A and the CIA-B, is
slightly modified versions of IC 6526, which is equipped with 
Commodore-64. They have 2 programmruemyh 8-bit

Parallel I / O ports, 2
16-bit time counter, bi-directional timer generates an 
interrupt when zeroing. CIA - multifunction circuit. Possible, 
for example, calling certain routines with a periodicity just 3 
milliseconds. 


                KEYBOARD

               ************


        The most noticeable I / O device is the keyboard. She 
has a microprocessor, and its attendant

generates the appropriate codes. The keyboard is made using a 
conductive rubber, which provides sufficient strength, although 
the use of reed reliability would be higher. The keys need

in the constant care and cleaning.


                DRIVE

               ***********


        Amiga equipped with a 3.5 "drive
(Inches). Floppy disk of this diameter are quite reliable and 
have good capacity. Disc formatted on a computer Amiga has 850 
kB of free space, while the absence of reserve space for system 
files we get 900 kB recording files. Drive controller, located

on-chip PAULA very versatile: it
can read a lot of data formats,
used in other computers, including
IBM, ATARI ST, MACINTOSH - and for the latter is used 
adjustable rate rotation of the disk!



        By the Amiga computer, you can connect up to four 
drives, but it should be remember that the power supply is not 
designed to the use of such options. This limitation can be 
eliminated by using self- power supply of the kits service

equipment for this type of computer. In practice, enough 
external drive 5.25 "(inches), in addition, it significantly

less than 3.5 "(inches). Amiga 500 and
Amiga 2000 are designed so that
that you can connect two drives
a 3.5 "drive and one 5.25", the latter can be used for
diskettes in the format IBM, if the computer
man up the appropriate cartridge with a hardware emulator, 
available at sale.



           I / O Connectors

          **********************

From left to right connectors:

- Port 0 - mouse, a second joystick, an analog input;

- Port 1 - the first joystick, analog
input;

- Sound - right channel;

- The sound - the left channel;

- Connector for optional
disk drives (up to three units);

- Serial port RS 232C: Modem
Interface MIDI, network;

- Parallel Centronix: printer, sampler;

- Video output - RGB: monitor, Modulator
TV signal;

- Video output for black and white monitor.


        The right to housing is still a system connector, which 
displays all important signals. Amiga 2000 has apart

This series of sockets that are intended to
connecting various boards, similar to how it was done at IBM.


        What else can you connected?

       ***************************


        Service kit for your computer
Amiga have a variety of interfaces, expansion cards of which 
should be noted: 

- Hard disk;

- Interface MIDI;

- Board math coprocessor,
speeding up the computer;

- Hardware emulator IBM XT / AT;

- Sampler;

- Genlock - a device to connect
Amiga professional equipment TV
with the ability to mix and manipulate
images.