Atari 1200 XL, Руководство по обслуживанию на месте

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From left to right the function keys and LED indicators are:
RESET - Interrupts and restarts the operating system or cartridge.
POWER - Lights when Power to the unit is ON.
L1 - Lights if the keyboard is disabled.
L2 - Lights if the International character set is selected. START - Starts the game or program.
SELECT - Selects different games.
OPTION - Allows the player to choose among the variations of a program.
F1-F4 - User programmable function keys. The following functions are only applicable when
software, such as BASIC; is inserted.
Press F 1 to move cursor up.
Press F2 to move cursor down.
Press F3 to move cursor left.
Press F4 to move cursor right.
HELP - Press to display self-test options.
- Inverse Video
BREAK - Used for interrupt of program.
Mechanical Description
The 1200XL computer console contains a single motherboard which houses all the chips of the
system and provides connectors for interfacing external modules to the console. It includes the
CPU, RAM, ROM Operating System and power supply, and includes all functions except for
the keyboard and LED display. The motherboard uses a common address bus, data bus and
clock lines. The sixteen-line address bus allows the microprocessor to directly address 64K of
memory locations. The eight-line data bus provides the communication and data path between
the functional modules. The various power requirements are routed from the power supply
throughout the console.
The keyboard is connected to the PC Board by a 15-conductor ribbon cable terminating in a
molex connector. The LED board is connected to the PC Board by a 5-conductor ribbon cable.
Figure 1-3 is a block diagram of the functional flow of the 1200XL.
1200XL Home Computer
Field Service Manual
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