CC2510FX Datasheet, PDF (161/253 Pages) List of Unclassifed Manufacturers – True System-on-Chip with Low Power RF Transceiver and 8051 MCU

CC2510Fx / CC2511Fx
44.1
16
48
16
9.21201
8.46354
0x8A
0x06
0x2F
0x59
0x1B
no
0xC0
yes
Table 48 Example I2S Clock Configurations (CC2510Fx, 26 MHz)
13.14.8.2 Word Size
The word size must be set before master
mode is enabled. The word size is the
number of bits used for each sample and
can be set to a value between 1 and 33.
To set the word size, write word size – 1 to
the I2SCFG.WORDS[4:0] bits. Setting
the word size to a value of 17 or more
causes the I2S to pad each word with 0’s
in the least significant bits since the data
registers provide maxmum 16 bits. This
feature allows samples to be sent to an
I2S device that takes a higher resolution
than 16 bits.
If the size of received samples exceeds 16
bits, only the 16 most significant bits will
be put in the data registers and the
remaining low order bits will be discarded.
13.14.9 Slave Mode
The I2S is configured as a slave device by
setting I2SCFG0.MASTER to 0. When in
slave mode the SCK and WS signals are
generated by an external I2S master and
are inputs to the I2S interface.
13.14.9.1 Word Size
When the I2S operates in slave mode, the
word size is determined by the master that
generates the WS signal.
The I2S will provide bits from the internal
16-bit buffer until the buffer is empty. If the
buffer becomes empty and the master still
requests more bits, the I2S will send 0’s
(low order bits).
If more than 16 bits are being received,
the low order bits are discarded.
13.14.10
Mono
The I2S also supports mono audio
samples.
To receive mono samples, set the
I2SCFG0.RXMONO bit to 1. Words from
the right channel will then not be read into
the data registers. This feature is included
because some mono devices repeat their
audio data in both channels and the left
channel is the default mono channel.
To send mono samples, set the
I2SCFG0.TXMONO bit to 1. Each word will
then be repeated in both channels before
a new word is fetched from the data
registers. This is to enable sending a
mono audio signal to a stereo audio sink
device.
13.14.11
Word Counter
The I2S contains a 10-bit word counter
that counts the number of transitions on
the WS line since the last time the word
counter was cleared.
Triggers are used to clear the word
counter. When a trigger occurs or software
writes any value to the I2SWCNT register,
the current value of the word counter is
copied into the WCNT[9:0] field in the
I2SWCNT/I2SSTAT registers and the
word counter is cleared.
Three triggers can be used to copy/clear
the word counter.
• USB SOF: USB Start of Frame.
Occurs every ms.
• T1_CH0: Timer 1, compare,
channel 0
• IOC_1: IO pin input transition
When the I2S is configured not to use any
trigger, the word counter can only be
copied/cleared from software.
The I2SCFG1.TRIGNUM[1:0] field
selects the trigger source.
The word counter will saturate if it reaches
its maximum value. Software should
configure the trigger-interval and sample-
rate to ensure this never happens.
CC2511Fx: The word counter is typically
used to calculate the average sample rate
over a long period of time (e.g. 1 second)
needed by adaptive isochronous USB
endpoints. The USB SOF event must then
be used as trigger.
CC2510Fx/CC2511Fx PRELIMINARY Data Sheet (Rev. 1.2) SWRS055A Page 161 of
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