Tektronix 070-9778-03, Service Manual

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TLA 711 Color Benchtop Controller Service Manual
3–1
Theory of Operation
This chapter contains a block level description of the benchtop controller. This
information supports fault isolation to the module, and replaceable part level.
Refer to the Diagrams section for a block level diagram of the benchtop
controller.
Block Level Description
The Block Level Description describes circuit operation to the functional block
level.
The benchtop controller is a high-performance personal computer based
controller including graphics and I/O. The primary difference between the
benchtop controller and a standard personal computer is the communications bus
interface used to communicate with the benchtop chassis and the instrument
modules. The benchtop controller consists of two boards, the controller board
and the adapter board.
The controller board is a personal computer controller utilizing standard Intel
Pentium-AT architecture. The controller board has a PCI to PCMCIA PC card
host adapter that is used to control the two PC card slots. The controller has one
ECP/EEP Centronics compatible parallel port, and two 16550 based serial
RS-232 COM ports (one external) to support standard PC based I/O peripherals.
The adapter board provides both electrical and mechanical support to the
controller board. The adapter board supports the hard and floppy disk drives,
keyboard and mouse ports, PC speaker, decoding and buffering to the commu-
nications bus.
The hard disk drive is a standard 2.5 inch IDE drive which interfaces directly to
the controller via an Enhanced Integrated Device Electronics (IDE) extension of
the PCI bus.
The floppy disk drive is a standard 1/2 inch drive that supports 3.5 inch,
1.44 MByte high density/double sided floppy disks.
The mouse and keyboard ports are standard PS2 compliant ports interfaced by
the adapter board to the controller.
Controller Board
Adapter Board
Hard Disk Drive
Floppy Disk Drive
Mouse and Keyboard
Ports