Tabor 8020, Руководство пользователя

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4-9-6-3. Suffix Program Data
A <Suffix Program Data> element permits the use
of a suffix following the <Decimal Numeric Program
Data> (NRf). The suffix expression associated units
and (optional) multipliers that modify how the NRf
is interpreted by the device. The presence of a
<Suffix Program Data> after an NRf is always optional.
No particular <Command Program Header> or <Query
Program Header> is a device shall require the use
of a <Suffix Program Data> element.
4-9-6-4. Non-Decimal Numeric Program Data
The <Non-Decimal Program Data> functional element
is not implemented in Model 8020. Therefore it shall
not be discussed in this manual.
4-9-6-5. Arbitrary Block Program Data
The <Arbitrary Block Program Data> functional ele-
ment is not implemented in Model 8020. Therefore
it shall not be discussed in this manual.
4-9-6-6. Expression Program Data
The <Expression Program Data> functional element
is not implemented in Model 8020. Therefore it shall
not be discussed in this manual.
4-10. DEVICE-DEPENDENT COMMAND
PROGRAMMING
IEEE-488.2 device-dependent commands are sent to
the Model 8020 to control various operating conditions
such as display modify, operating mode, output and
parameter interrogate. Each command is made up
of a program, command or query header followed
by program data, program suffix, and terminated by
program message terminator. The IEEE bus treats
device-dependent commands as data in, providing
that ATN is high when the commands are transmitted.
For example the output amplitude is programmed
by sending the following <Program Message Unit>:
AMP 10.5V.
A number of <Program Message Unit> elements
may be grouped together in one <Program Message>
provided that each <Program Message Unit> is sepa-
rated by a <Program Message Unit Separator>.
<Program message Unit> elements within a <Program
Message> are executed exactly in the same order
they are received from the controller. The Model
8020 ignores all non-printable ASCII characters (00
HEX through 20 HEX) except the “CR” (carriage
return). A command string is terminated by a <Pro-
gram Message Terminator> which tells the instrument
to execute the <Program Message>.
If an illegal <Program Header> or <Program Data>
is present within a <Program Message>, the instru-
ment will:
1. Ignore the illegal part or the <Program Mes-
sage> (but will execute the rest of the <Pro-
gram Message>).
2. Display an appropriate front panel error mes-
sage.
3. Set certain bits in its status registers.
4. Generate an SRQ if programmed to do so.
Device-dependent programming aspects are cov-
ered in paragraph 4-8-5 and 4-10.
NOTE
Before programming the instrument
over the bus, It is recommended that
the instrument be set to its default
values by sending an SDC or DCL
over the bus. See paragraph 4-8-3
for information on using the SDC
command.
In order to send a device-dependent or a common
command, the controller must perform the following
sequence:
1. Set ATN true.
2. Address the Model 8020 to listen.
3. Set ATN false.
4. Send the command string over the data bus
one byte at a time.
NOTE
REN must be true when attempting
to program the Model 8020.
Device-dependent commands that affect Models
8020, 8021, and 8022 are listed in Table 4-5.
Common commands and queries are listed in Table
4-6. All the commands listed in the Tables 4-5 and
4-6 are covered in detail in the following.
4-10-1. Display (D)
The display modify command controls what the
Model 8020 places on the display. The eight pa-
rameters associated with the display command set
the instrument to display the frequency, amplitude,
IEEE-488.2 Operation Model 8020
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