Rockwell SoniCrafter BT8960 - Manual (Page 58)

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3.0 Registers
3.1 Conventions
Bt8960
Single-Chip 2B1Q Transceiver
N8960DSB
3.2.8 0x07—Receive Phase Select Register (receive_phase_select)
rphs[3:0] Receive Phase Select—Read/write binary field that defines the relative phase relationship
between QCLK and the sampling point of the ADC. The rising edges of QCLK corresponds to
the ADC sampling point when rphs = 0000. Each binary increment of rphs represents a one-
sixteenth QCLK period delay in the sampling point relative to QCLK.
3.2.9 0x08—Linear Echo Canceller Modes Register (linear_ec_modes)
enable_dc_tap Enable DC Tap—Read/write control bit which, when set, forces a constant +1 value into the
last data tap of the Linear Echo Canceller (LEC). This condition enables cancellation of any
residual DC offset present at the input to the LEC. When cleared, the last data tap operates nor-
mally, as the oldest transmit data sample.
adapt_coefficents Adapt Coefficients—Read/write control bit which enables coefficient adaptation when set; dis-
ables/freezes adaptation when cleared. Coefficient values are preserved when adaptation is dis-
abled.
zero_coefficients Zero Coefficients—Read/write control bit that continuously zeros all coefficients when set;
allows normal coefficient updates, if enabled, when cleared. This behavior differs slightly from
the similar function (zero_coefficients) of the FFE and EP filters.
Interface
mode
[1:0]
Mode
Pin Functions
91 90 88 89 85 86
00 Parallel Master —Parallel quat transfer
synchronized to QCLK out. Not
used Not
used RQ[1] RQ[0] TQ[1] TQ[0]
01 Parallel Slave—Parallel quat transfer
synchronized to separate TBCLK and
RBCLK inputs. TBCLK RBCLK RQ[1] RQ[0] TQ[1] TQ[0]
10 Serial, Magnitude First. Serial quat
transfer synchronized to BCLK out;
magnitude-bit first followed by sign bit. Not
used Not
used RDAT BCLK TDAT Not
used
11 Serial, Sign First. Serial quat transfer
synchronized to BCLK out; sign-bit first
followed by magnitude bit. Not
used Not
used RDAT BCLK TDAT Not
used
7 6 5 4 3 2 1 0
– – – – rphs[3] rphs[2] rphs[1] rphs[0]
7 6 5 4 3 2 1 0
– – enable_dc_tap
adapt_
coefficients
zero_coefficients zero_output adapt_gain[1] adapt_gain[0]