AN332
64
Confidential Rev. 0.2
Command 0x21. FM_SEEK_START
Begins searching for a valid frequency. Clears any pending STCINT or RSQINT interrupt status. The CTS bit (and
optional interrupt) is set when it is safe to send the next command. The ERR bit (and optional interrupt) is set if an
invalid argument is sent. Note that only a single interrupt occurs if both the CTS and ERR bits are set. The optional
STC interrupt is set when the command completes. The STCINT bit is set only after the GET_INT_STATUS
command is called. This command may only be sent when in powerup mode. The command clears the STCINT bit
if it is already set. See Figure 17, “CTS and STC Timing Model,” on page 187 and Table 42, “Command Timing
Parameters for the FM Receiver,” on page 188.
Command arguments: One
Response bytes: None
Command
Response
Bit
D7
D6
D5
D4
D3
D2
D1
D0
CMD
0
0
1
0
0
0
0
1
ARG1
0
0
0
0
SEEKUP
WRAP
0
0
ARG
Bit
Name
Function
1
7:4
Reserved
Always write to 0.
1
3
SEEKUP
Seek Up/Down.
Determines the direction of the search, either UP = 1, or DOWN = 0.
1
2
WRAP
Wrap/Halt.
Determines whether the seek should Wrap = 1, or Halt = 0 when it hits the
band limit.
1
1:0
Reserved
Always write to 0.
Bit
D7
D6
D5
D4
D3
D2
D1
D0
STATUS
CTS
ERR
X
X
RSQINT
RDSINT
X
STCINT