Freescale Semiconductor DSP56374 User Manual page 41

Table 2-9. Enhanced Serial Audio Interface_1 Signals (continued)
Signal Name Signal Type
FSR_1 Input or Output
PE1 Input, Output, or
Disconnected
FST_1 Input or Output
PE4 Input, Output, or
Disconnected
Freescale Semiconductor
State during
Reset
GPIO Frame Sync for Receiver_1—This is the receiver frame
Disconnected sync input/output signal. In the asynchronous mode
(SYN=0), the FSR_1 pin operates as the frame sync input
or output used by all the enabled receivers. In the
synchronous mode (SYN=1), it operates as either the serial
flag 1 pin (TEBE=0), or as the transmitter external buffer
enable control (TEBE=1, RFSD=1).
When this pin is configured as serial flag pin, its direction is
determined by the RFSD bit in the RCCR_1 register. When
configured as the output flag OF1, this pin will reflect the
value of the OF1 bit in the SAICR_1 register, and the data
in the OF1 bit will show up at the pin synchronized to the
frame sync in normal mode or the slot in network mode.
When configured as the input flag IF1, the data value at the
pin will be stored in the IF1 bit in the SAISR_1 register,
synchronized by the frame sync in normal mode or the slot
in network mode.
Port E1—When the ESAI_1 is configured as GPIO, this
signal is individually programmable as input, output, or
internally disconnected.
The default state after reset is GPIO disconnected.
This pin has an internal pull-down resistor.
This input is 5 V tolerant
GPIO Frame Sync for Transmitter_1—This is the transmitter
Disconnected frame sync input/output signal. For synchronous mode, this
signal is the frame sync for both transmitters and receivers.
For asynchronous mode, FST_1 is the frame sync for the
transmitters only. The direction is determined by the
transmitter frame sync direction (TFSD) bit in the ESAI_1
transmit clock control register (TCCR_1).
Port E4—When the ESAI_1 is configured as GPIO, this
signal is individually programmable as input, output, or
internally disconnected.
The default state after reset is GPIO disconnected.
This pin has an internal pull-down resistor.
This input is 5 V tolerant.
DSP56374 Users Guide, Rev. 1.2
Enhanced Serial Audio Interface_1
Signal Description
2-13