Radio Shack TRS-80 Model 4

Specifications
Mode14
The Radio Shack TRS-80 Model 4 is a ROM/disk-based computer
system with one major part:
• A display console/keyboard unit with one or two built-in,
single-sided, double-density, floppy disk drives (disk system)
or zero disk drives (cassette system)
The operating system software is loaded from ROM or
an operating
system disk
in Drive 0 by a built-in read-only memory (ROM)
"bootstrap" program.
Mode14P
The Radio Shack TRS-80 Model 4P is a disk-based computer system
with one major part:
• A display console/keyboard unit with two built-in, single-sided,
double-density, floppy disk drives
The operating system software is loaded from
an operating system
disk
in Drive 0 by a built-in read-only memory (ROM) "bootstrap"
program.
Console
Processor
Mode14
• The TRS-80 Model 4 is a Z-80A based high-speed
microprocessor with 64K or optional 128K of memory (disk
system) or 16K of memory (cassette system)
• The processor receives power-up and reset instructions from
ROM.
• The Model 4 is compatible with existing Model
III software.
Mode14P
• The TRS-80 Model 4P is a Z-80A based high-speed
microprocessor with 64K or optional 128K of memory
• The processor receives power-up and reset instructions from
ROM
• The Model 4P is compatible with existing Model
III disk
software.
Sound
The disk system can generate software-controlled tones, one at a
time.
A-39