HP 1660CP Series User Manual page 292

The Analyzer Hardware
HP 1660CP-series analyzer theory
HP-IB interface
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
control signal transfer between the bus and controller.
RS-232-C interface
The instrument RS-232-C interface is compatible with standard RS-232-C
protocol. The interface consists of a controller and drivers/receivers. The
controller serializes parallel data from the microprocessor for transmission.
At the same time the 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. Other RS-232-C communications parameters
can also be programmed from the logic analyzer front panel.
The drivers/receivers interface the instrument with data communications
equipment. Slew rate control is provided on the ICs, eliminating the need for
external capacitors.
Power supply
A low voltage power supply provides all dc voltages needed to operate the
logic analyzer. The power supply also provides the +5 V dc 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.
10-24