HP 1660 Series User Manual

External Keyboard InterfaceExternal Keyboard Interface
HP propriet ary ICs make up the external keyboard interface. The ICs establish a link with
the controller IC on the external keyboard. The keyboard signals are routed through the
acquisition circuit board to the CPU board. The microprocessor then reads and interprets
the external keyboard and mouse information and performs the desired tasks.
HP-I B I nt er faceHP-I B I nt er face
The instrument interfaces to HP-IB as defined by IEEE Standard 488.2. The interface
consists of an HP-IB controller and two octal drivers/receivers. The microprocessor routes
HP-IB data to the controller. The controller then buffers the 8-bit HP-IB data bits and
generates the bus handshaking signals. The data and handshaking signals are then routed to
the HP-IB bus through the octal line drivers/receivers. The drivers/receivers provide data
and cont rol signal t ransfer bet ween the bus and controller.
RS-232C InterfaceRS-232C Interface
The instrument RS-232C interface is compatible with standard RS-232C protocol. The
interface consists of a controller, and drivers/receivers. The controller serializes parallel data
from t he microprocessor for t ransmission. At t he same t ime t he controller also receives
serial data and converts the data to parallel data characters for the microprocessor.
The controller contains a baud rate generator that can be programmed from the logic
analyzer front panel for one of eight baud rates. Other RS-232C communications parameters
can also be programmed from the logic analyzer front panel.
The drivers/receivers int erface the instrument with data communications equipment. Slew
rate control is provided on the ICs eliminating the need for external capacitors.
CRT Monitor AssemblyCRT Monitor Assembly
The CRT Monitor Assembly consists of a monochrome CRT and a monitor driver board. The
monitor driver board provides the biasing and control signals for the CRT. Pixel information
is stored in the display RAM on the CPU board and is routed to the monitor driver board
through the acquisition board and the sweep cable.
Disk Drive Disk Drive
The disk drive assembly is a high density disk drive that formats double-sided, double-density
or high density disks in LIF or DOS format. A disk drive controller on the CPU board controls
the disk drive. Signals are routed directly to the disk drive through the disk drive cable.
Power SupplyPower Supply
A low voltage power supply provides all DC voltages needed to operate the logic analyzer.
The power supply also provides the +5 Vdc voltage to the probe cables to power logic
analyzer accessories and preprocessors.
Unfiltered voltages of +12 V, -12 V, +5 V, -5.2 V, and +3.5 V are supplied to the acquisition
board where they are filtered and distributed to the CPU board, CRT Monitor Assembly, and
probe cables.
Theory of Operation
The HP 1660 Series Logic Analyzer
8–5

HP 1660 Series Specifications

General

Category	Logic Analyzer
Glitch Trigger	Yes
Pattern Trigger	Yes
State Analysis	Yes
Transitional Timing	Yes
Trigger Modes	Edge, Pattern, Glitch