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Series 3700A System Switch/Multimeter Reference Manual
Section 2: Installation
3700AS-901-01 Rev. D/June 2018
2-31
To write-protect specific digital I/O lines to prevent their values from being changed:
1. Press the
MENU
key, then select
DIGIO
, and then press the
ENTER
key or the navigation wheel
.
2. Select
WRITE-PROTECT
, and then press the
ENTER
key or the navigation wheel .
3. Set the decimal value as required to write-protect digital I/O lines within the range of 0 to 16,383
(see
(on page 2-31)), and then press the
ENTER
key or the navigation
wheel .
For example, to write-protect digital I/O lines 4 and 10, set the value to 520.
4. Press the
EXIT (LOCAL)
key as needed to return to the main menu.
To remove write protection, reset the decimal value to include only the lines that you want to write
protect. To remove write protection from all lines, set the value to 0.
Digital I/O bit weighting
Bit weighting for the digital I/O lines is shown in the following table.
Digital bit weight
Line # Bit
Decimal
weighting
Hexadecimal
weighting
1
B1
1
0x0001
2
B2
2
0x0002
3
B3
4
0x0004
4
B4
8
0x0008
5
B5
16
0x0010
6
B6
32
0x0020
7
B7
64
0x0040
8
B8
128
0x0080
9
B9
256
0x0100
10
B10
512
0x0200
11
B11
1,024
0x0400
12
B12
2,048
0x0800
13
B13
4,096
0x1000
14
B14
8,192
0x2000
Remote digital I/O commands
Commands that control and access the digital I/O port are summarized in the following table. See the
(on page 11-1) for complete details on these commands. See the following
table for decimal and hexadecimal values used to control and access the digital I/O port and
individual lines. Use these commands to trigger the Series 3700A using external trigger pulses
applied to the digital I/O port, or to provide trigger pulses to external devices.
Use these commands to perform basic steady-state digital I/O operations such as reading and writing
to individual I/O lines or reading and writing to the entire port.