SPEAR300-2 View Datasheet(PDF) - STMicroelectronics
Part Name
Description
MFG CO.
SPEAR300-2
STMicroelectronics
'SPEAR300-2' PDF : 83 Pages View PDF
Architecture overview
SPEAr300
2.16
SPI_I2C multiple slave control
The SPI interface has only one slave select signal, SS0.
The I2C interface does not allow control of several devices with the same address, which is
frequently required for CODECs.
The SPI_I2C extension allows management of up to 8 SPI devices, or 8 I2C devices at the
same address (total SPI+I2C devices=8).
The SPI extension is made by generating three more slave select signals SS1, SS2 and
SS3.
The I2C extension is done by replicating the I2C_SCL signal if the corresponding pin is set
active.Otherwise the pin remains low, so that the start condition is not met.
Each of the 8 pins can reproduce either the SPI SS0 signal, or the I2C_SCL signal. The
selection is made through a register.
2.17
TDM interface
The TDM block implements time division multiplexing.
Main features:
● TDM interface with 512 timeslots and up to 16 bufferization channels.
● 32 ms bufferization for 16 channels (of 4 bytes each)
● Supports master and slave mode operation
● Programmable clock and synchronization signal generation in master mode
● Clock & synchronization signal recovery in slave mode
● 8 programmable synchronization signals for CODECs
● Uses 11 pins:
– SYNC7-0 are dedicated frame syncs for CODECs without timeslot recognition
– CLK is the TDM clock
– DIN is the TDM input and receives the data
– DOUT is the TDM output and transmits the data. It can be high impedance on a
unused timeslot
● The TDM interface can be the master or a slave of the CLK or SYNC0 signals.
● Timeslots can be used for switching or bufferization purposes:
– Switching and bufferization can be used concurrently for different timeslots on the
same TDM
– The only limitation is that an output timeslot can not be switched and bufferized at
the same time.
– Timeslot switching: any of the output time slots can receive any input timeslot of
the previous frame. The connection memory is part of the action memory,
indicating which timeslot has to be output.
– Timeslot bufferization: data from DIN is stored in an input buffer and data from an
output buffer is played on DOUT. When the number of samples stored/played
reaches the buffer size, the processor is interrupted in order to read the input
buffer and prepare a new output buffer (or a DMA request is generated).
20/83
Doc ID 16324 Rev 2
Share Link: 