USART Operation: SPI Mode
18-11
USART Peripheral Interface, SPI Mode
18.2.6 SPI Interrupts
The USART has one interrupt vector for transmission and one interrupt vector
for reception.
SPI Transmit Interrupt Operation
The UTXIFGx interrupt flag is set by the transmitter to indicate that UxTXBUF
is ready to accept another character. An interrupt request is generated if
UTXIEx and GIE are also set. UTXIFGx is automatically reset if the interrupt
request is serviced or if a character is written to UxTXBUF.
UTXIFGx is set after a PUC or when SWRST = 1. UTXIEx is reset after a PUC
or when SWRST = 1. The operation is shown is Figure 18−10.
Figure 18−10. Transmit Interrupt Operation
Clear
UTXIEx
Clear
D
Character Moved From
Buffer to Shift Register
Interrupt Service Requested
SWRST
Data moved to UxTXBUF
Q
UTXIFGx
IRQA
V
CC
PUC or SWRST
Q
Set
SYNC = 1
Note:
Writing to UxTXBUF in SPI Mode
Data written to UxTXBUF when UTXIFGx = 0 and USPIEx = 1 may result in
erroneous data transmission.
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 ...