Silicon Laboratories Si4700, Руководство по программированию, Страница: 113 / 256

AN332
Confidential Rev. 0.2 113
Response
Command 0x41. AM_SEEK_START
Initiates a seek for a channel that meets the RSSI and SNR criteria for AM. 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 43, “Command Timing Parameters for the AM Receiver,” on page 189.
Command arguments: One
Response bytes: None
Command
Response
Bit D7 D6 D5 D4 D3 D2 D1 D0
STATUS CTS ERR X X RSQINT X X STCINT
Bit D7 D6 D5 D4 D3 D2 D1 D0
CMD 0 1 0 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 X X STCINT