sta339bw STMicroelectronics, sta339bw Datasheet - Page 60

• Manufacturer Part Number: sta339bw
• Description: 2.1-channel High-efficiency Digital Audio System
• Manufacturer: STMicroelectronics

Register description
60/77
Writing a single coefficient to RAM
1.
2.
3.
4.
5.
6.
Writing a set of coefficients to RAM
1.
2.
3.
4.
5.
6.
7.
8.
9.
10. Write middle 8-bits of coefficient a1 in I
11. Write bottom 8-bits of coefficient a1 in I
12. Write top 8-bits of coefficient a2 in I
13. Write middle 8-bits of coefficient a2 in I
14. Write bottom 8-bits of coefficient a2 in I
15. Write top 8-bits of coefficient b0 in I
16. Write middle 8-bits of coefficient b0 in I
17. Write bottom 8-bits of coefficient b0 in I
18. Write 1 to WA bit in I
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
STA339BW generates the RAM addresses as offsets from this base value to write the
complete set of coefficient data.
Select the RAM block with register 0x31 bit1, bit0.
Write 6-bits of address to I
Write top 8-bits of coefficient in I
Write middle 8-bits of coefficient in I
Write bottom 8-bits of coefficient in I
Write 1 to W1 bit in I
Select the RAM block with register 0x31 bit1, bit0.
Write 6-bits of starting address to I
Write top 8-bits of coefficient b1 in I
Write middle 8-bits of coefficient b1 in I
Write bottom 8-bits of coefficient b1 in I
Write top 8-bits of coefficient b2 in I
Write middle 8-bits of coefficient b2 in I
Write bottom 8-bits of coefficient b2 in I
Write top 8-bits of coefficient a1 in I
2
2
C address 0x26.
C address 0x26.
Doc ID 15251 Rev 4
2
C register 0x16.
2
C address 0x17.
2
2
2
2
2
2
C register 0x16.
2
2
C address 0x17.
C address 0x1A.
C address 0x1D.
C address 0x20.
C address 0x23.
C address 0x18.
C address 0x19.
2
2
2
2
2
2
2
2
2
2
C address 0x18.
C address 0x1B.
C address 0x1E.
C address 0x21.
C address 0x24.
C address 0x19.
C address 0x1C.
C address 0x1F.
C address 0x22.
C address 0x25.
STA339BW