LM3S828 Datasheet, PDF (400/526 Pages) Texas Instruments – ARM and Thumb are registered trademarks and Cortex is a trademark

Synchronous Serial Interface (SSI)
12 Synchronous Serial Interface (SSI)
12.1
The Stellaris^® Synchronous Serial Interface (SSI) is a master or slave interface for synchronous
serial communication with peripheral devices that have either Freescale SPI, MICROWIRE, or Texas
Instruments synchronous serial interfaces.
The Stellaris SSI module has the following features:
■ Master or slave operation
■ Programmable clock bit rate and prescale
■ Separate transmit and receive FIFOs, 16 bits wide, 8 locations deep
■ Programmable interface operation for Freescale SPI, MICROWIRE, or Texas Instruments
synchronous serial interfaces
■ Programmable data frame size from 4 to 16 bits
■ Internal loopback test mode for diagnostic/debug testing
Block Diagram
Figure 12-1. SSI Module Block Diagram
Interrupt
Control/ Status
SSICR0
SSICR1
SSISR
Interrupt Control
SSIIM
SSIMIS
SSIRIS
SSIICR
SSIDR
System Clock
SSIPCellID 0
SSIPCellID 1
SSIPCellID 2
SSIPCellID 3
Identification
Registers
SSIPeriphID0 SSIPeriphID 4
SSIPeriphID1 SSIPeriphID 5
SSIPeriphID2 ^{SSIPeriphID 6}
SSIPeriphID 3 SSIPeriphID7
Clock
Prescaler
SSICPSR
TxFIFO
8 x16
.
.
.
RxFIFO
8 x16
.
.
.
SSITx
Transmit /
Receive
Logic
SSIRx
SSIClk
SSIFss
12.2
Signal Description
Table 12-1 on page 401 lists the external signals of the SSI module and describes the function of
each. The SSI signals are alternate functions for some GPIO signals and default to be GPIO signals
400
June 18, 2012
Texas Instruments-Production Data