Elmo Network Hardware HARSFEN0602 ユーザーズマニュアル

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Elmo HARmonica Software Manual
 
P R E L I M I N A R Y   D R A F T
 
HARSFEN0602
 
 
 
 
 
200 
For more details about gain scheduling, refer the section " The Gain-Scheduling Algorithm". 
15.4.2 User 
Interface 
The parameters defined by an 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 n <= 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 = 
floor(log2(X))-30; 
If X <0 
      Exp = ceil(log2(-X))-31; 
Man = floor(
X / 2^Exp) 
 
15.4.2.1 An 
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: