sta339bws STMicroelectronics, sta339bws Datasheet - Page 59

• Manufacturer Part Number: sta339bws
• Description: 2.1-channel High-efficiency Digital Audio System
• Manufacturer: STMicroelectronics

STA339BWS
Note:
For example, in case of different input sources (different sampling rates), the three different
sets of coefficients can be downloaded once at the start up, and during the normal play it is
possible to switch among the three RAM blocks allowing a faster operation, without any
additional download from the microcontroller.
To write the coefficients in a particular RAM bank, this bank must be selected first writing
bit 0 and bit 1 in register 0x31. Then the write procedure below can be used.
Note that as soon as a RAM bank is selected, the EQ settings are automatically switched to
the coefficients stored in the active RAM block.
The read and write operation on RAM coefficients works only if LRCKI (pin 29) is switching.
Reading a coefficient from RAM
1.
2.
3.
4.
5.
6.
Reading a set of coefficients from RAM
1.
2.
3.
4.
5.
6.
7.
8.
9.
10. Read top 8-bits of coefficient a1 in I
11. Read middle 8-bits of coefficient a1 in I
12. Read bottom 8-bits of coefficient a1 in I
13. Read top 8-bits of coefficient a2 in I
14. Read middle 8-bits of coefficient a2 in I
15. Read bottom 8-bits of coefficient a2 in I
16. Read top 8-bits of coefficient b0 in I
17. Read middle 8-bits of coefficient b0 in I
18. Read bottom 8-bits of coefficient b0 in I
Select the RAM block with register 0x31 bit1, bit0.
Write 6-bits of address to I
Write 1 to R1 bit in I
Read top 8-bits of coefficient in I
Read middle 8-bits of coefficient in I
Read bottom 8-bits of coefficient in I
Select the RAM block with register 0x31 bit1, bit0.
Write 6-bits of address to I
Write 1 to RA bit in I
Read top 8-bits of coefficient in I
Read middle 8-bits of coefficient in I
Read bottom 8-bits of coefficient in I
Read top 8-bits of coefficient b2 in I
Read middle 8-bits of coefficient b2 in I
Read bottom 8-bits of coefficient b2 in I
2
2
C address 0x26.
C address 0x26.
2
2
C register 0x16.
C register 0x16.
2
2
C address 0x17.
C address 0x17.
2
2
2
2
2
2
2
2
C address 0x1A.
C address 0x1D.
C address 0x20.
C address 0x23.
C address 0x18.
C address 0x18.
C address 0x19.
C address 0x19.
2
2
2
2
2
2
2
2
C address 0x1B.
C address 0x1E.
C address 0x21.
C address 0x24.
C address 0x1C.
C address 0x1F.
C address 0x22.
C address 0x25.
Register description
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