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Siemens FB3:Derive calc-Derive calculation

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mascalzone
Junior
Junior

Joined: 20 Nov 2016
Posts: 11

Posted: 14/01/2017 19:02 Post subject: Siemens FB3:Derive calc-Derive calculation

FB3 - <offline>
"FB3:Derive calc" Derive calculation

Siemens FB3:Derive calc-Derive calculation Siemens FB3:Derive calc-Derive calculation

This function calculate the 1st derive of [Input_value]
The derive is calculate on 20 samples of [Input_value] the samples are take each time [CLK] is TRUE
The output value is the sum of 1st 10 samples with 2nd 10 samples.

Code:

Parameters:
.[Input_value]: Value to derive
.[Reset]: This command reset the act derive value. The calculation restart 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

Segmento: 1 Reset
This network manages the reset command
U #Reset // Reset command
R #Derive_calc_ON

Segmento: 2 Timing
This network manage the timing of function
U #Derive_spl_CMD
BLD 100
FP #Dummy_bit_1
= #Calc_ON // One-shot clock
UN #Calc_ON // Timng calculation
R #Enable
BEB // End block

Segmento: 3 1st derive calculation
This network manages the calculation of [Input_value] 1st derive
// *************************************** Derive calculation *****************************************//
U #Derive_calc_ON // **** Reset derive value ****
SPB Calc
L 0
T #Derive_value
SPA Shf // Jump derive calculation
Calc: L 0
T #Index // Init array index
T #Prev_sum // Init 1st 10 samples sum
T #Next_sum // Init 2nd 10 samples sum
L 5
Lab: T #Loop // Load loop index
L #Funct_pointer // Load derive function pointer
LAR1 // Load pointment register
L P##Samples // Load array pointer
+AR1 // ADD to pointment register
L #Index // Load pointer of array index
SLD 3
+AR1 // Sum the array pointer to inex pointer
L DID [AR1,P#0.0] // Load pointed sample
L #Prev_sum
+R
T #Prev_sum // Add the act sample to prev sum
L DID [AR1,P#20.0] // Load pointed sample plus 5
L #Next_sum
+R
T #Next_sum // Add the act sample plus 5 to next sum
L 4
L #Index
+I // Array index increment
T #Index
L #Loop
LOOP Lab // Loop end
L #Prev_sum // 1st derive calculation
L #Next_sum
-R
//L 5.000000e+000
///R // ([Prev_sum]-[Next-sum])/25
T #Derive_value
//
// ********************************* 1 item to right array shifting ***********************************//
Shf: L 32
T #Index // Load array index whit address of 9th item
L 9
Lab1: T #Loop // Load loop index
L #Funct_pointer // Load the pointer to derive function
LAR1 // Load pointement register
L P##Samples // Load the pointer of array samples
+AR1 // ADD to pointement register
L #Index // Load the pointer of act sample
SLD 3
+AR1 // Sum the pointer of array with the pointer of 19th sample
L DID [AR1,P#0.0]
T DID [AR1,P#4.0] // Shift the samples of 1 item to right
L #Index
L 4
-I // Array index decrement
T #Index
L #Loop
SIMATIC Simone_gen\Derivate calc\...\FB3 - <offline> 07/20/2000 18:57:35
Pagina 3
LOOP Lab1 // Loop end

Segmento: 4 Add new sample to array
This network add a new sample to array
L #Funct_pointer
LAR1
L P##Samples
+AR1
L #Input_value
T DID [AR1,P#0.0] // Insert new sample to 1ft array field
SET
SAVE
S #Enable
L #Nr_of_shf // # of shifted samples calculation
L 1
+I
T #Nr_of_shf

Segmento: 5 Array init end calculation start
This network manages the activation of derive calculation start (when array
initialization is finish)
L #Nr_of_shf // # of shifted samples
L 9
>=I // Array init end
= #Init_end
U #Init_end
S #Derive_calc_ON // Set derive calculation start
U(
O #Init_end // Reset coomand
O #Reset
)
SPBNB Jmp
L 0 // Reset # of shifted samples
T #Nr_of_shf
Jmp: NOP 0

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