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Current revision as of 02:41, 21 September 2009

Derivative Calculation

contributed by: Simone Stefani

Link to File

Click here to view program file.

Abstract

This function calculates the 1st derivative of [Input_value]. The derivative is calculated on 20 samples of [Input_value] - the samples are taken each time [CLK] is TRUE. The output value is the sum of the 1st 10 samples with 2nd 10 samples.

Parameters:

• [Input_value]: Value to derive
• [Reset]: This command resets the act derive value. The calculation restarts when all the items of samples array are refreshed.
• [Derive_spl_CMD]: Timing step. The samples are taken when [Derive_spl_CMD] = TRUE
• [Derive_value]: Derivated output value
• [Enable]: This output is energized when the calculation of act value is finished
• [Samples]: Samples container.
• [Nr_samples]: # of samples to take for calculation
• [Derive_calc_ON]: System variable
• [Nr_of_shf]: System variable
• [Loop]: System variable
• [Index]: System variable
• [Prev_sum]: System variable
• [Next_sum]: System variable
• [Dummy_bit_1]: System variable
• [Calc_ON]: System variable
• [Init_end]: System variable

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