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STA380BW
Register description: New Map
Writing a set of coefficients to RAM
1.
Write 6 bits of the starting address to I
2
C register 0x27.
2. Write the top 8 bits of coefficient b1 in I
2
C address 0x28.
3. Write the middle 8 bits of coefficient b1 in I
2
C address 0x29.
4. Write the bottom 8 bits of coefficient b1 in I
2
C address 0x2A.
5. Write the top 8 bits of coefficient b2 in I
2
C address 0x2B.
6. Write the middle 8 bits of coefficient b2 in I
2
C address 0x2C.
7. Write the bottom 8 bits of coefficient b2 in I
2
C address 0x2D.
8. Write the top 8 bits of coefficient a1 in I
2
C address 0x2E.
9. Write the middle 8 bits of coefficient a1 in I
2
C address 0x2F.
10. Write the bottom 8 bits of coefficient a1 in I
2
C address 0x30.
11. Write the top 8 bits of coefficient a2 in I
2
C address 0x31.
12. Write the middle 8 bits of coefficient a2 in I
2
C address 0x32.
13. Write the bottom 8 bits of coefficient a2 in I
2
C address 0x33.
14. Write the top 8 bits of coefficient b0 in I
2
C address 0x34.
15. Write the middle 8 bits of coefficient b0 in I
2
C address 0x35.
16. Write the bottom 8 bits of coefficient b0 in I
2
C address 0x36.
17. Write 1 to the WA bit in I
2
C address 0x37.
The mechanism for writing a set of coefficients to RAM provides a method of updating the
five coefficients corresponding to a given biquad (filter) simultaneously to avoid possible
unpleasant acoustic side effects. When using this technique, the 6-bit address specifies the
address of the biquad b1 coefficient (for example, 0, 5, 10, 20, 35 decimal), and the
STA380BW generates the RAM addresses as offsets from this base value to write the
complete set of coefficient data.
Obsolete Product(s) - Obsolete Product(s)