USCI Operation: SPI Mode
20-10
Universal Serial Communication Interface, SPI Mode
20.3.5 SPI Enable
When the USCI module is enabled by clearing the UCSWRST bit it is ready
to receive and transmit. In master mode the bit clock generator is ready, but
is not clocked nor producing any clocks. In slave mode the bit clock generator
is disabled and the clock is provided by the master.
A transmit or receive operation is indicated by UCBUSY = 1.
A PUC or set UCSWRST bit disables the USCI immediately and any active
transfer is terminated.
Transmit Enable
In master mode, writing to UCxTXBUF activates the bit clock generator and
the data will begin to transmit.
In slave mode, transmission begins when a master provides a clock and, in
4-pin mode, when the UCxSTE is in the slave-active state.
Receive Enable
The SPI receives data when a transmission is active. Receive and transmit
operations operate concurrently.
Summary of Contents for MSP430x4xx Family
Page 1: ...MSP430x4xx Family 2007 Mixed Signal Products User s Guide SLAU056G ...
Page 2: ......
Page 6: ...vi ...
Page 114: ...3 76 RISC 16 Bit CPU ...
Page 304: ...5 20 FLL Clock Module ...
Page 340: ...7 8 Supply Voltage Supervisor ...
Page 348: ...8 8 16 Bit Hardware Multiplier ...
Page 372: ...9 24 32 Bit Hardware Multiplier ...
Page 400: ...10 28 DMA Controller ...
Page 428: ...13 10 Basic Timer1 ...
Page 466: ...15 24 Timer_A ...
Page 522: ...17 30 USART Peripheral Interface UART Mode ...
Page 544: ...18 22 USART Peripheral Interface SPI Mode ...
Page 672: ...23 12 Comparator_A ...
Page 692: ...24 20 LCD Controller ...
Page 746: ...26 28 ADC12 ...