Keithley 7707, Руководство пользователя

Страница: 25 / 59

22
Setting digital outputs
Before setting a digital output pattern, an I/O channel must first be set as an output port. This can be done from the front panel
or remote programming.
From the front panel, the pattern for each 8-bit port must be set individually. For remote programming, commands are
provided to set 8-bit patterns (bytes), 16-bit patterns (words) and a 32-bit pattern (double-word).
From the front panel, each 8-bit port is set using a decimal, hexadecimal, or octal value that is the equivalent of the binary
output bit pattern. For remote programming, an output bit pattern can be set using decimal, binary, hexadecimal, or octal
values.
Figure 18
Decimal weighting for 32-bit output pattern (double-word)
Channel 11 (B0 - B7)
Digital I/O line: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Bit position: B7 B6 B5 B4 B3 B2 B1 B0
Binary bit pattern: 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1
Decimal weight: 128
(2
7
)
64
(2
6
)
32
(2
5
)
16
(2
4
)
8
(2
3
)
4
(2
2
)
2
(2
1
)
1
(2
0
)
Channel 12 (B8 - B15)
Digital I/O line: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Bit position: B15 B14 B13 B12 B11 B10 B9 B8
Binary bit pattern: 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1
Decimal weight: 32768
(2
15
)
16384
(2
14
)
8192
(2
13
)
4096
(2
12
)
2048
(2
11
)
1024
(2
10)
512
(2
9
)
256
(2
8
)
Channel 13 (B16 - B23)
Digital I/O line: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Bit position: B23 B22 B21 B20 B19 B18 B17 B16
Binary bit pattern: 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1
Decimal weight*: 2
23
2
22
2
21
2
20
2
19
2
18
2
17
2
16
Channel 14 (B24 - B31)
Digital I/O line: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Bit position: B31 B30 B29 B28 B27 B26 B25 B24
Binary bit pattern: 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1
Decimal weight*: 2
31
2
30
2
29
2
28
2
27
2
26
2
25
2
24
* 2
16
= 65536
2
17
= 131072
2
18
= 262144
2
19
= 524288
2
20
= 1048576
2
21
= 2097152
2
22
= 4194304
2
23
= 8388608
2
24
= 16777216
2
25
= 33554432
2
26
= 67108864
2
27
= 134217728
2
28
= 268435456
2
29
= 536870912
2
30
= 1073741824
2
31
= 2147483648