DSP56374 Datasheet, PDF (13/64 Pages) Motorola, Inc – high density CMOS device with 3.3 V inputs and outputs

Signal Groupings
Table 10. Enhanced Serial Audio Interface Signals (continued)
Signal Name Signal Type
FSR
Input or output
State during
Reset
Signal Description
GPIO
disconnected
Frame Sync for Receiver—This is the receiver frame sync
input/output signal. In the asynchronous mode (SYN=0),
the FSR 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).
PC1
Input, output, or
disconnected
When this pin is configured as serial flag pin, its direction is
determined by the RFSD bit in the RCCR register. When
configured as the output flag OF1, this pin will reflect the
value of the OF1 bit in the SAICR 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 register,
synchronized by the frame sync in normal mode or the slot
in network mode.
Port C1—When the ESAI is configured as GPIO, this signal
is individually programmable as input, output, or internally
disconnected.
The default state after reset is GPIO disconnected.
Internal Pull down resistor.
This input is 5 V tolerant.
FST
Input or output
GPIO
Frame Sync for Transmitter—This is the transmitter frame
disconnected sync input/output signal. For synchronous mode, this signal
is the frame sync for both transmitters and receivers. For
asynchronous mode, FST is the frame sync for the
transmitters only. The direction is determined by the
transmitter frame sync direction (TFSD) bit in the ESAI
transmit clock control register (TCCR).
PC4
Input, output, or
disconnected
Port C4—When the ESAI is configured as GPIO, this signal
is individually programmable as input, output, or internally
disconnected.
The default state after reset is GPIO disconnected.
Internal Pull down resistor.
This input is 5 V tolerant.
DSP56374 Data Sheet, Rev. 4.2
Freescale Semiconductor
13