BC41B143A-DS-003PC Datasheet, PDF (65/94 Pages) List of Unclassifed Manufacturers – BlueCore 4-ROM Plug-n-Go Single Chip Bluetooth v2.0 + EDR System

Device Terminal Descriptions
10.6.2 Writing to BlueCore4-ROM Plug-n-Go
To write to BlueCore4-ROM Plug-n-Go, the 8-bit write command (00000010) is sent first (C[7:0]) followed by a 16-bit
address (A[15:0]). The next 16-bits (D[15:0]) clocked in on SPI_MOSI are written to the location set by the address
(A). Thereafter for each subsequent 16-bits clocked in, the address (A) is incremented and the data written to
consecutive locations until the transaction terminates when SPI_CSB is taken high.
Figure 10.16: Write Operation
10.6.3 Reading from BlueCore4-ROM Plug-n-Go
Reading from BlueCore4-ROM Plug-n-Go is similar to writing to it. An 8-bit read command (00000011) is sent first
(C[7:0]), followed by the address of the location to be read (A[15:0]). BlueCore4-ROM Plug-n-Go then outputs on
SPI_MISO a check word during T[15:0] followed by the 16-bit contents of the addressed location during bits D[15:0].
The check word is composed of {command, address [15:8]}. The check word may be used to confirm a read operation
to a memory location. This overcomes the problems encountered with typical serial peripheral interface slaves,
whereby it is impossible to determine whether the data returned by a read operation is valid data or the result of the
slave device not responding.
If SPI_CSB is kept low, data from consecutive locations is read out on SPI_MISO for each subsequent 16 clocks, until
the transaction terminates when SPI_CSB is taken high.
Figure 10.17: Read Operation
10.6.4 Multi-Slave Operation
BlueCore4-ROM Plug-n-Go should not be connected in a multi-slave arrangement by simple parallel connection of
slave MISO lines. When BlueCore4-ROM Plug-n-Go is deselected (SPI_CSB = 1), the SPI_MISO line does not float.
Instead, BlueCore4-ROM Plug-n-Go outputs 0 if the processor is running or 1 if it is stopped.
BC41B143A-ds-003Pc
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