Spectrum Brands MC.31XX manual Setting up the inputs, Input ranges

Analog Inputs Setting up the inputs

Setting up the inputs

Input ranges

This analog acquisition board uses separate input amplifiers and converters on each channel. This gives you the possibility to set up the de- sired and concerning your application best suiting input range also separately for each channel. The input ranges can easily be set by the corresponding input registers. The table below shows the available input registers and possible standard ranges for your type of board. As there are also modified version availble with different input ranges it is recommended to read out the currently available input ranges as shown later in this chapter.

Register	Value	Direction	Description
SPC_AMP0	30010	r/w	Defines the input range of channel0.
SPC_AMP1	30110	r/w	Defines the input range of channel1.
SPC_AMP2	30210	r/w	Defines the input range of channel2.
SPC_AMP3	30310	r/w	Defines the input range of channel3.
SPC_AMP4	30410	r/w	Defines the input range of channel4.
SPC_AMP5	30510	r/w	Defines the input range of channel5.
SPC_AMP6	30610	r/w	Defines the input range of channel6.
SPC_AMP7	30710	r/w	Defines the input range of channel7.
	50	± 50 mV calibrated input range for the appropriate channel.
	100	± 100 mV calibrated input range for the appropriate channel.
	200	± 200 mV calibrated input range for the appropriate channel.
	500	± 500 mV calibrated input range for the appropriate channel.
	1000	± 1 V calibrated input range for the appropriate channel.
	2000	± 2 V calibrated input range for the appropriate channel.
	5000	± 5 V calibrated input range for the appropriate channel.
	10000	± 10 V calibrated input range for the appropriate channel.

The different input ranges are set with the help of relais. These relais need a settling time if they are changed, so that the relais are fully set and didn’t influence the signal when the board is started. The following table shows the related register to adjust the wait time. Any changes of the wait time below the default value should only be done after detailed tests of the boards behaviour. Setting lower values may be possible or may not be possible depending on the application that is done.

Register	Value	Direction	Description
SPC_RELAISWAITTIME	200700	read/write	Wait time in ms for relais settling before the start of the board. Default value is 50 ms.

If you want to know, how many different input ranges are available on the actual board per channel, you can easily read that information by using the read-only register shown in the table below.

Register	Value	Direction	Description
SPC_READIRCOUNT	3000	r	Informs about the number of the board’s calibrated input ranges.

Additionally cou can read out the minimum and the maximum value of each input range as shown in the table below. The number of input ranges is read out with the above shown register.

Register	Value	Direction	Description
SPC_READRANGEMIN0	4000	r	Gives back the minimum value of input range 0 in mV.
SPC_READRANGEMIN1	4001	r	Gives back the minimum value of input range 1 in mV.
SPC_READRANGEMIN2	4002	r	Gives back the minimum value of input range 2 in mV.
...	...	r	...
SPC_READRANGEMAX0	4100	r	Gives back the maximum value of input range 0 in mV.
SPC_READRANGEMAX1	4101	r	Gives back the maximum value of input range 1 in mV.
SPC_READRANGEMAX2	4102	r	Gives back the maximum value of input range 2 in mV.
...	...	r	...

The following example reads out the number of available input ranges and reads and prints the minimum and maximum value of all input ranges.

SpcGetParam	(hDrv, READIRCOUNT,		&lNumberOfRanges);
for (i = 0;	i <	lNumberOfRanges; i++)
{		(hDrv, SPC_READRANGEMIN0 + i, &lMinimumInputRage);
SpcGetParam
SpcGetParam		(hDrv, SPC_READRANGEMAX0 + i, &lMaximumInputRange);

printf („Range %d: %d mV to %d mV\n“, i, lMinimumInputRange, lMaximumInputRange);

}

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