Information

I2Sx_TCR2 field descriptions
Field Description
31–30
SYNC
Synchronous Mode
Configures between asynchronous and synchronous modes of operation. When configured for a
synchronous mode of operation, the receiver must be configured for asynchronous operation.
00 Asynchronous mode.
01 Synchronous with receiver.
10 Synchronous with another SAI transmitter.
11 Synchronous with another SAI receiver.
29
BCS
Bit Clock Swap
When the SAI is in asynchronous mode and this field is set to 1, the transmitter is clocked by the receiver
bit clock. When the SAI is in synchronous mode and this field is set to 1, the transmitter is clocked by the
transmitter bit clock, but it uses the receiver frame sync.
0 Use the normal bit clock source.
1 Swap the bit clock source.
28
BCI
Bit Clock Input
When set in either asynchronous or synchronous mode and using an internally generated bit clock,
configures the internal logic to be clocked as if the bit clock was externally generated. This has the effect
of decreasing data input setup time, but increasing data output valid time. This bit has no effect when
configured for an externally generated bit clock.
0 No effect.
1 Internal logic is clocked by external bit clock.
27–26
MSEL
MCLK Select
Selects the Audio Master Clock used to generate an internally generated bit clock. This field has no effect
when configured for an externally generated bit clock.
00 Bus Clock selected.
01 Master Clock 1 selected.
10 Master Clock 2 selected.
11 Master Clock 3 selected.
25
BCP
Bit Clock Polarity
Configures the polarity of the bit clock.
0 Bit clock is active high with drive outputs on rising edge and sample inputs on falling edge.
1 Bit clock is active low with drive outputs on falling edge and sample inputs on rising edge.
24
BCD
Bit Clock Direction
Configures the direction of the bit clock.
0 Bit clock is generated externally in Slave mode.
1 Bit clock is generated internally in Master mode.
23–8
Reserved
This read-only field is reserved and always has the value zero.
Table continues on the next page...
Chapter 46 Synchronous Audio Interface (SAI)
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
Freescale Semiconductor, Inc. 1153