Fluke NetDAQ 2640A, Service Manual

Page: 200 / 260

NetDAQ
Service Manual
5-36
The frequency counter calibration constant is simply the Gain constant calculation where
the lowTarget and lowMeas are both assumed to be zero.
FrequencyConstant = targetFreq / measFreq
To retrieve the calibration constants, set up the instrument in the manual calibration
configuration described in “Calibration Procedure (Manual)“ in Chapter 4. Then retrieve
the desired calibration constant with the CAL_CONST? xx command, where xx denotes
the calibration constant number shown in Table 5-15. Each constant reflects the
correction applied to the uncompensated measurement result as an offset or as a gain
multiplier. For example,
CAL_CONST? 8
might 998.939E-3 indicating the
uncompensated value for the 3V dc range is multiplied by 0.998939 to achieve
specification.
Loading Embedded Instrument Firmware 5-38.
Instrument firmware consists of the following components:
Main Firmware Loaded from a floppy disk on the PC to the instrument via the
instrument rear panel RS-232 port. This is a closed-case procedure and it is not
necessary to open the instrument to load the Main Firmware. The Main Firmware is
identical for both model instruments.
A/D Firmware Loaded from a floppy disk on the PC to the instrument directly to a
3-pin connection on the A3 A/D Converter PCA. This also requires a separate power
supply connection to the A3 A/D Converter PCA Flash Memory, and custom cables for
making the connections. This is not a closed-case procedure and it is necessary to open
the instrument to load the A/D Firmware. The A/D Firmware is different for each
instrument.
Firmware is stored in the instrument in electrically erasable and programmable memory
devices. A diskette containing the necessary loading software and latest release of the
firmware may be obtained from either your local Fluke authorized service center, or
from the Fluke factory. You may also contact the factory directly: Fluke Data
Acquisition Sales Support, (206) 356-5870 or FAX, (206) 356-5790.
To review which versions of the Main and A/D firmware are presently in your
instrument, see “Diagnostic Tool idS” earlier in this chapter. The listing for A/D
Firmware is identified as
AtodM ; the listing for Main Firmware is identified as Main .
The remaining firmware for the display, FPGA and so forth are factory procedures only.
Firmware Diskette 5-39.
The firmware diskette contains the files shown in Table 5-16. The
*.bat
files are used for
the standard installation of the firmware. If you wish to customize the installation, then do
not run the batch file, but refer to Table 5-16 for the switches used for the executable file
ld26xx.exe
. Create a directory on your hard drive for this diskette and then copy the
contents to the hard drive. For example, create the directory on your hard drive called
firmware and copy the contents of the diskette into this directory. (Refer to your
Windows or DOS documentation if you need information on creating directories or
copying files.)