Spectrum M2p.59 Series, Руководство по оборудованию, Страница: 78 / 190

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Setting up the inputs Analog Inputs
that can be saved within the on-board EEPROM. The default settings of the offset and gain values are then read-only and cannot be written
to the EEPROM by the user. If the card has no user settings the default settings may be overwritten.
You can easily either save adjustment settings to the EEPROM with SPC_ADJ_SAVE or recall them with SPC_ADJ_LOAD. These two registers
are shown in the table below. The values for these EEPROM access registers are the sets that can be stored within the EEPROM. The amount
of sets available for storing user offset settings depends on the type of board you use. The table below shows all the EEPROM sets, that are
available for your board.
If you want to make an offset and gain adjustment on all the channels and store the data to the ADJ_DEFAULT set of the EEPROM you can
do this the way, the following example shows.
Read out of input features
The analog inputs of the different cards do have different features implemented, that can be read out to make the software more general. If
you only operate one single card type in your software it is not necessary to read out these features.
Please note that the following table shows all input features settings that are available throughout all Spectrum acquisition cards. Some of
these features are not installed on your specific hardware.
Table 31: Spectrum API: loading and storing calibration values to the EEPROM
Register Value Direction Description
SPC_ADJ_LOAD 50000 write Loads the specified set of settings from the EEPROM. The default settings are automatically loaded,
when the driver is started.
read Reads out, what kind of settings have been loaded last.
SPC_ADJ_SAVE 50010 write Stores the current settings to the specified set in the EEPROM.
read Reads out, what kind of settings have been saved last.
ADJ_DEFAULT 0 Default settings, no user settings available
spcm_dwSetParam_i32 (hDrv, SPC_ADJ_AUTOADJ, ADJ_ALL ); // Activate offset/gain adjustment on all channels
spcm_dwSetParam_i32 (hDrv, SPC_ADJ_SAVE , ADJ_DEFAULT); // and store values to DEFAULT set in the EEPROM
Table 32: Spectrum API: readout register for analog input features with list of all possible input features
Register Value Direction Description
SPC_READAIFEATURES 3101 read Returns a bit map with the available features of the analog input path. The possible return values are
listed below.
SPCM_AI_TERM 00000001h Programmable input termination available, otherwise the termination is fixed in value.
SPCM_AI_SE 00000002h Input is single-ended. If available together with SPC_AI_DIFF or SPCM_AI_DIFFMUX: input type is software selectable.
SPCM_AI_DIFF 00000004h Input is differential. If available together with SPC_AI_SE: input type is software selectable and switching from single-
ended to differential does not reduce the number of active channels by combining two single-ended channels.
SPCM_AI_OFFSPERCENT 00000008h Input offset programmable in per cent of input range
SPCM_AI_OFFSMV 00000010h Input offset programmable in mV
SPCM_AI_OVERRANGEDETECT 00000020h Programmable overrange detection available
SPCM_AI_DCCOUPLING 00000040h Input is DC coupled. If available together with AC coupling: coupling is software selectable
SPCM_AI_ACCOUPLING 00000080h Input is AC coupled. If available together with DC coupling: coupling is software selectable
SPCM_AI_LOWPASS 00000100h Input has a selectable low pass filter (bandwidth limit)
SPCM_AI_DIFFMUX 00000400h Input is differential. If available together with SPC_AI_SE: input type is software selectable and switching from single-
ended to differential does reduce the number of active channels due to combining two single-ended channels.
SPCM_AI_AUTOCALOFFS 00001000h Input offset can be auto calibrated on the card
SPCM_AI_AUTOCALGAIN 00002000h Input gain can be auto calibrated on the card
SPCM_AI_AUTOCALOFFSNOIN 00004000h Input offset can auto calibrated on the card if inputs are left open
SPCM_AI_HIGHIMP 00008000h Input can be high-impedance. When also SPCM_AI_LOWIMP is set, the impedance is software programmable.
SPCM_AI_LOWIMP 00010000h Input can be low-impedance. When also SPCM_AI_HIGHIMP is set, the impedance is software programmable.
SPCM_AI_INDIVPULSEWIDTH 00100000h Trigger pulsewidth is individually per channel programmable