Tandy 1000 HX Technical Reference Manual page 7

. TANDY COMPUTER PRODUCTS
INTRODUCTION TO THE TANDY 1000 HX COMPUTER
The Tandy 1000 HX Computer is modular in design to allow
maximum flexibility in system configuration. The computer
consists of a Main Unit, and a monitor. The Main Unit is
supplied with one 3 1/2" internal disk drive. A second
internal 3 1/2" disk drive is optional. Each disk drive has
a capacity of 720K bytes formatted. The standard types of
monitors used with the Tandy 1000 HX are the monochrome
composite and the color RGB monitor.
The Tandy 1000 HX has a standard 256K of system RAM. An
optional DMA/RAM board allows the Tandy 1000 HX to be
expanded by 128K or 384K of RAM. This board will fit onto
the expansion slot. With a fully populated RAM board
installed, the Tandy 1000 HX will have 640K bytes of RAM
allowed by the system memory map.
Other features include a parallel printer port, two built-in
joystick interfaces, and a headphone connection for private
listening.
The Main Unit is the heart of the Tandy 1000 HX. It houses
the Main Logic Assembly, system power supply,
internal 3 1/2" disk drive, and keyboard.
The Main Logic Assembly is a large board mounted to the
bottom of the Main Unit and interconnected to the keyboard,
power supply, and disk drive by a series of cables. Figure 1
shows the Tandy 1000 HX.
The Power Supply is a 28W switching regulator type, designed
to provide adequate power capacity for a fully configured
system.
The Internal 3 1/2" Disk Drive uses double-sided,
double-density diskettes to read, write, or store data.
These are soft sector diskettes. The Disk Drive assembly is
installed in the standard unit. All system programs, with
the exception of the system startup sequence, are stored on
disk.