AN332
Rev. 0.8
71
Command
Response
Bit
D7
D6
D5
D4
D3
D2
D1
D0
CMD
0
0
1
0
0
0
0
0
ARG1
0
0
0
0
0
0
FREEZE
FAST
ARG2
FREQ
H
[7:0]
ARG3
FREQ
L
[7:0]
ARG4
ANTCAP[7:0]
ARG
Bit
Name
Function
1
7:1
Reserved
Always write to 0.
1
1
FREEZE
Freeze Metrics During Alternate Frequency Jump.
If set will cause the blend, hicut, and softmute to transition as a function of the
associated attack/release parameters rather than instantaneously when tuning
to alternate station.
1
0
FAST
FAST Tuning.
If set, executes fast and invalidated tune. The tune status will not be accurate.
2
7:0
FREQ
H
[7:0]
Tune Frequency High Byte.
This byte in combination with FREQ
L
selects the tune frequency in 10 kHz. In
FM mode the valid range is from 6400 to 10800 (64–108 MHz).
3
7:0
FREQ
L
[7:0]
Tune Frequency Low Byte.
This byte in combination with FREQ
H
selects the tune frequency in 10 kHz. In
FM mode the valid range is from 6400 to 10800 (64–108 MHz).
4
7:0
ANTCAP[7:0]
Antenna Tuning Capacitor (valid only when using TXO/LPI pin as the
antenna input).
This selects the value of the antenna tuning capacitor manually, or automati-
cally if set to zero. The valid range is 0 to 191. Automatic capacitor tuning is
recommended.
Note:
When tuned manually, the varactor is offset by four codes. For example, if the
varactor is set to a value of 5 manually, when read back the value will be 1. The
four codes (1pf) delta accounts for the capacitance at the chip.
Bit
D7
D6
D5
D4
D3
D2
D1
D0
STATUS
CTS
ERR
X
X
RSQINT
RDSINT
X
STCINT