Instrument control package: Difference between revisions
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Xavier mtb (talk | contribs) (→MacOS: Add a workarround to install the package if rpcgen cannot be build from source and the VXI-11 interface is not required.) |
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# Prerequisits are that during install of the NI drivers, the C/C++ support | # Prerequisits are that during install of the NI drivers, the C/C++ support | ||
# and the NI Measurement & Automation explorer has been enabled. | # and the NI Measurement & Automation explorer has been enabled. | ||
# set the base for includes and libraries on your system | |||
# it is usually /usr, but on newer windows installs of octave, it will be | |||
# /mingw64 | |||
INSTALL_BASE=/usr | |||
# this define should find the NI header file, if properly installled | # this define should find the NI header file, if properly installled | ||
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# symlink NI header file | # symlink NI header file | ||
mkdir -p | mkdir -p ${INSTALL_BASE}/include/gpib/ | ||
ln -sf "${NI_H_FILE}" | ln -sf "${NI_H_FILE}" ${INSTALL_BASE}/include/gpib/ib.h | ||
# generate .def for all functions in the NI header file with a NI488CC prefix | # generate .def for all functions in the NI header file with a NI488CC prefix | ||
echo LIBRARY ${NI_DLL_FILE} > ${NI_DEF_FILE} | echo LIBRARY ${NI_DLL_FILE} > ${NI_DEF_FILE} | ||
echo EXPORTS >> ${NI_DEF_FILE} | echo EXPORTS >> ${NI_DEF_FILE} | ||
grep "NI488CC *[A-Za-z]" | grep "NI488CC *[A-Za-z]" ${INSTALL_BASE}/include/gpib/ib.h \ | ||
| sed "s/^.*NI488CC *//" \ | | sed "s/^.*NI488CC *//" \ | ||
| sed "s/(.*$//" >> ${NI_DEF_FILE} | | sed "s/(.*$//" >> ${NI_DEF_FILE} | ||
# generate the wrapper library simulating gpib-linux | # generate the wrapper library simulating gpib-linux | ||
dlltool -d ${NI_DEF_FILE} -l | dlltool -d ${NI_DEF_FILE} -l ${INSTALL_BASE}/lib/libgpib.a | ||
#cleanup | #cleanup | ||
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You need to build '''rpcgen''' from source [http://mirror.ancl.hawaii.edu/pub/FreeBSD/FreeBSD-current/src/usr.bin/rpcgen]. | You need to build '''rpcgen''' from source [http://mirror.ancl.hawaii.edu/pub/FreeBSD/FreeBSD-current/src/usr.bin/rpcgen]. | ||
If | If rpcgen cannot be build from source, the following error might be obtained: | ||
<syntaxhighlight style="font-size:13px"> | <syntaxhighlight lang="text" style="font-size:13px"> | ||
pkg: error running `make' for the instrument-control package. | pkg: error running `make' for the instrument-control package. | ||
error: called from | error: called from | ||
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== i2c == | == i2c == | ||
i2c | Example with a Si7021 i2c breakout board (https://www.sparkfun.com/products/1376) connected to a i2c master interface. | ||
To work out the devices available (assuming i2ctools are installed) run the i2cdetect command from a terminal window. | |||
<syntaxhighlight lang="bash" style="font-size:13px"> | |||
$ i2cdetect -l | |||
i2c-1 i2c i2c-ch341-usb at bus 002 device 008 I2C adapter | |||
i2c-0 unknown SMBus I801 adapter at 4000 N/ | |||
</syntaxhighlight> | |||
In the example case the temperature sensor is connected to the i2c-ch341-usb device, and it is assumed the user has sufficient permissions to access the device. | |||
According to the datasheet, the temperature device uses address 0x40, so create a i2c device using the linux device and address: | |||
<syntaxhighlight lang="octave" style="font-size:13px"> | |||
i2cdev = i2c("/dev/i2c-1", 0x40) | |||
</syntaxhighlight> | |||
To read the temperature, register 0xF3 must be addressed and read (2 bytes of data): | |||
<syntaxhighlight lang="octave" style="font-size:13px"> | |||
TEMP_MEASURE_NOHOLD = hex2dec("F3"); | |||
fwrite (i2cdev, uint8([TEMP_MEASURE_NOHOLD])); | |||
pause (0.02); | |||
data = fread (i2cdev, 3); | |||
</syntaxhighlight> | |||
The data must be converted to a deg K value by making 16 bit number of the value and masking out unused bits. | |||
<syntaxhighlight lang="octave" style="font-size:13px"> | |||
value = uint16(data(1))*256 + uint16(data(2)); | |||
value = bitand (value, hex2dec("FFFC")); | |||
temp_Code = double(value); | |||
</syntaxhighlight> | |||
Now convert the temperature to degrees C and display: | |||
<syntaxhighlight lang="octave" style="font-size:13px"> | |||
C = (175.72*temp_Code/65536)-46.85; | |||
printf ("temperature read %f C\n", C); | |||
</syntaxhighlight> | |||
== TCP == | == TCP == | ||