Campbell CR9000, Инструкция по эксплуатации

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Section 7. Measurement Instructions
7-26
WriteIO (PSlot, Mask, Source)
WriteIO is used to set the status of selected digital I/O channels (ports) on the
CR9070/CR9071E Counter - Timer / Digital I/O Module. (See PortSet for
setting the Output channels on the CR9060.) There are 16 ports on the
CR9070/CR9071E. The status of these ports is considered to be a binary
number with a high port (+5 V) signifying 1 and a low port (0 V) signifying 0.
For example, just looking at the first 8 ports, if ports 1 and 3 are high and the
rest low, the binary representation is 00000101, or 5 decimal. The source
value is interpreted as a binary number and the ports set accordingly. The
mask parameter is used to select which of the ports to set, it too is a binary
representation of the ports, a 1 means set the port according to the source, a 0
means do not change the status of the port. CRBasic allows the entry of
numbers in binary format by preceding the number with "&B". For example if
the mask is entered as &B110 (leading zeros can be omitted in binary format
just as in decimal) and the source is 5 decimal (binary 101) port 3 will be set
high and port 2 will be set low. The mask indicates that only 3 and 2 should be
set. While the value of the source also has a 1 for port 1, it is ignored because
the mask indicates 1 should not be changed.
Examples
WriteIO (5, &B100, &B100) ' Set
port 3 on the 9070 in slot 5 high.
WriteIO (5, &Hff00, Y*256) ' Write
Y to upper 8 ports (9-16)
Parameter
& Data Type
Enter
WRITEIO INSTRUCTION PARAMETERS
PSlot
Constant
The number of the slot that holds the CR9070/CR9071E Counter Timer Module for the measurement.
Mask
Constant
The Mask allows the read or write to only act on certain ports. The Mask is ANDed with the value
obtained from the 9070 when reading and ANDed with the source before writing.
Source
Constant
Variable
The Variable or number that is to be written to the I/O ports.
7.9 CR9052DC Filter Module Measurements
The CR9052DC is a six-channel, analog-input module that includes
programmable anti-alias filtering and dc excitation. The CR9052DC can
provide filtered voltage measurements or spectra from fast fourier transforms
of the voltage measurements. See Section 3.3 for additional measurement
details.
The filter module collects alias-free, 50-kHz samples from each of its six
analog-to-digital converters; applies additional real-time, finite-impulse-
response filtering, and decimates (down samples) the 50-kHz data to the
programmed scan rate. The Filter Module supports 726 different scan intervals
including the basic ones shown in the table below. For scan intervals not
listed, enter the scan interval desired, download the program, and the logger
will return suggested operational scan intervals close to the one that was
entered.