Silicon Laboratories Si4700, Руководство по программированию

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AN332
Confidential Rev. 0.2 51
Property 0x2C07. TX_RDS_FIFO_SIZE (Si4711/13/21 Only)
Sets the RDS FIFO size in number of blocks. Note that the value written must be one larger than the desired FIFO
size. The number of blocks allocated will reduce the size of the Circular RDS Group Buffer by the same amount.
For instance, if RDSFIFOSZ = 20, then the RDS Circular Buffer will be reduced by 20 blocks. The minimum
number of blocks which should be allocated is 4. This provides enough room for a single group of any type (xA or
xB) to be transmitted. Groups xA require 3 Blocks, Groups xB require 2 Blocks as block C' is always the same as
the RDS PI code. Before setting this value, determine the available blocks through the TX_RDS_FIFO command,
as the buffer size may vary between versions or part numbers. The guaranteed minimum FIFO size, however, is 53
blocks. The RDS FIFO and the RDS Circular Buffer should be emptied with the TX_RDS_FIFO command prior to
changing the size of the FIFO. The CTS bit (and optional interrupt) is set when it is safe to send the next command.
This property may only be set or read when in powerup mode.
Note: TX_RDS_FIFO_SIZE is supported in FMTX component 2.0 or higher.
Default: 0x0000
Units: blocks
Step: 3 blocks
Range: 0, 4, 7, 10–54
Note : Actual maximum FIFO size returned by the TX_RDS_BUFF command is larger, however, this is 53 blocks is
the guaranteed FIFO size.
Bit D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
Name
0 0 0 0 0 0 0 0 RDSFIFOSZ[7:0]
Bit Name Function
15:8 Reserved Always write 0.
7:0 RDSFIFOSZ[7:0]
Transmit RDS FIFO Size.
0 = FIFO disabled (default)