Ametek 7280 Instruction Manual page 195

storage. When a bit is negated, the output is not stored. The bit function and range for
each output are shown in the table below:
Bit Decimal value
0* 1
1* 2
2* 4
3* 8
4 16
5* 32
6* 64
7* 128
8* 256
9* 512
10* 1024
11* 2048
12* 4096
13* 8192
14 16384
15 32768
16 65536
Dual modes only:-
17 131072
18 262144
19 524288
20 1048576
21 2097152
32768 points are available for data storage, shared equally between the specified
curves. For example, if 16 outputs are stored then the maximum number of storage
points would be 2048 (i.e. 32768/16). The only exception to this rule is that the
Frequency curve (curves 15 and 16) occupies the equivalent of any two other curves.
The LEN command sets the actual curve length, which cannot therefore be longer
than 32768 divided by the number of curves selected. If more curves are requested
than can be stored with the current buffer length, then the buffer length will be
automatically reduced. Its actual length can of course be determined by sending the
LEN command without a parameter.
The reason why bit 4 and, for dual reference modes, bit 21, which store both the
sensitivity and the IMODE setting, are needed, is to allow the instrument to transfer
the acquired curves to the computer in floating point mode. Without this information,
the unit would not be able to determine the correct calibration to apply.
Note that the CBD command directly determines the allowable parameters for the
DC, DCB and DCT commands. It also interacts with the LEN command and affects
the values reported by the M command.
Since the reference frequency requires 32-bit wide data points, it occupies two curve
positions. For ease of use, if bit 15 is selected for storage then bit 16 will be
automatically selected as well, and vice-versa.
Appendix F, ALPHABETICAL LISTING OF COMMANDS
Output and range
X Output (±10000 FS)
Y Output (±10000 FS)
Magnitude Output (0 to +10000 FS)
Phase (±18000 = ±180°)
Sensitivity setting (3 to 27) + IMODE (0, 1, 2, 3 =
0, 32, 64, 128)
Noise (0 to +10000 FS)
Ratio (±10000 FS)
Log ratio (-3000 to +2000)
ADC1 (±10000 = ±10.0 V)
ADC2 (±10000 = ±10.0 V)
ADC3 (±10000 = ±10.0 V)
ADC4 (±10000 = ±10.0 V)
DAC1 (±10000 = ±10.0 V)
DAC2 (±10000 = ±10.0 V)
EVENT variable (0 to 32767)
Reference Frequency bits 0 to 15 (millihertz)
Reference frequency bits 16 to 31 (millihertz)
X Output (±10000 FS)
2
Y Output (±10000 FS)
2
Magnitude2 Output (0 to +10000 FS)
Phase Output (±18000 = ±180°)
2
Sensitivity setting (3 to 27) + IMODE
2
(0, 1, 2, 3 = 0, 32, 64, 128)
F-3