Rohde & Schwarz Hameg HM8150, Руководство пользователя

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Operation of the HM8150
actual signal frequency. When using such signals, it is im-
portant to keep in mind the effects that they can have on
circuits under test.
With the HM8150, arbitrary signals can only be defined by
the RS-232, GPIB or USB interface. Once such a signal has
been defined, it is stored in the memory of the HM8150
and can be dealt with just like one of the ”hard-wired“ sig-
nals. Please see paragraph REMOTE CONTROL for more
information.
he HM8150 is equipped with memory space in the form
of a 1024 x 1024 or 4096 x 4096-point matrix. This is equi-
valent to a resolution of 10 bits or 12 bits in horizontal and
vertical direction. The contents of this matrix correspond
to one signal period. The y-axis is for the amplitude values
and the x-axis represents is for the phase values.
With 10 bit resolution the possible amplitude values ex-
tend from -511 to +511 and the phase values from 0 to
1023. With 12 bit resolution the possible amplitude values
extend from – 2047 to +2047 and the phase values from 0
to 4095. A signal between –2047 and +2047 generates an
amplitude of ±10 V at the output of the HM8150 (without
load), if the amplitude is set to 20 V
pp
.
5 Remote control
5.1 Remote Interface Configuration
The function generator HM8150 supports remote inter-
face communication with two different interfaces: USB/
RS-232 and IEEE-488 (GPIB). The standard configuration is
the Dual-Interface USB/RS-232. Instead of this interface an
IEEE-488 (GPIB), HO880 can be built in (ex factory) as an
optional equipment. All interfaces are galvanically isolated.
If the HM8150 is controlled via interface, the REMOTE but-
ton is illuminated to indicate the remote control.
In the following part same interface parameters are descri-
bed, which might have to be changed:
5.2 RS-232 interface
No settings are necessary. If required, the baud rate can
be changed. Use a 1:1 serial cable for the connection with
your PC.
5.3 USB interface
You do not have to change the configuration. If required,
the baud rate can be changed. Connect the HM8150 with
your PC using a USB cable and install the USB drivers like
described in the manual of the USB interface HO820.
5.4 GPIB interface
It is necessary to change the GPIB adress of the function
generator to the desired value. The adress is changed at
the interface on the back panel. Connect the HM8150 with
your PC using a GPIB cable and set the baud rate to 9600
baud.
5.5 Interface parameters
Baud rate: 4800, 9600 (default), 19200
Data and stop bits: 8 data, 1 stop bit
Parity: none
Hand shake: none
5.6 Change of the baud rate
If you want to change the baud rate, turn of the func-
tion generator, push the OUTPUT button
8
. Turn on the
HM8150 again and keep the button pressed until you hear
several beeps. The new baud rate is shown in the display.
If you want to check the actual baud rate, re-start the
HM8150. During the initalisation procedure the actual
baud rate is shown in the display.
The baud rate has to be set to 9600 baud if the GPIB interface is
used.