= ceil(log2(-X))-31; X / 2^Exp)
floor(log2(X))-30;

HARSFEN0602ElmoHARmonicaSoftwareManual

PRELIMINARYDRAFT

For more details about gain scheduling, refer the section " The Gain-Scheduling Algorithm".

15.4.2User Interface

The parameters defined by array of long integer values set by the KV command. If KV[0]=0, high order filter is not used and the vector is ignored.

If KV[0] is not zero, the KV[2]..KV[n] defines the filter structure, where KV[1]=n, is the last index used. Anyway <= 100.

The filter consists of a number of blocks. It is possible to configure a filter flexible by user interface command KV, i.e. to define the list of blocks of given types.

KV[0]=100

KV[1]=Filter_Length (last index of KV used) Filter_structure

{

Block1{

KV[2] =Block_type

KV[3]… =Block_parameter_list

}

Block2{

}

Block_Last

{

KV[n]=Block_type=0

}

}

KV[last-2]=0 (reserved)

KV[last-1]=0 (reserved) KV[last]=-1 – terminator of list

Each block is represented as a list of parameters. The first parameter in each block is the block type, represented by one KV array element; the block type defines the length of the block parameter list and the meaning of every parameter.

Other parameters of a block are float values. Every float value x is represented by a pair of KV elements (Man, Exp) so that

X = Man*exp(Exp),

-2^31 <= Man <= 2^31-1,

-1000 <= Exp <= 32

The following formulae give the appropriate values: If X=0 the Exp =-1000

If X>0 then Exp =

If X <0

Exp

Man = floor(

15.4.2.1An Example

Consisted a filter made of one 2nd-order block and one 1st-order block.

The second order block is a notch filter with 300Hz notch frequency and damping of 0.14. The sample time is

400 us. The discrete equivalent of the filter is parameterized by k1 = 0.4038, k2=0.3447, k3= -0.7414, k4= 0.4900

The second block is simple pole with frequency 400 Hz. It may be represented by p=0.3659, q = 1-p =0.6341

The KV parameters vector is be programmed as follow:

200

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Elmo HARmonica, HARSFEN0602 software manual 200, User Interface, An Example