USART Operation: SPI Mode
18-12
USART Peripheral Interface, SPI Mode
SPI Receive Interrupt Operation
The URXIFGx interrupt flag is set each time a character is received and loaded
into UxRXBUF as shown in Figure 18−11 and Figure 18−12. An interrupt
request is generated if URXIEx and GIE are also set. URXIFGx and URXIEx
are reset by a system reset PUC signal or when SWRST = 1. URXIFGx is
automatically reset if the pending interrupt is served or when UxRXBUF is
read.
Figure 18−11.Receive Interrupt Operation
URXS
Clear
τ
(S)
SYNC
Valid Start Bit
Receiver Collects Character
URXSE
From URXD
PE
FE
BRK
URXEIE
URXWIE
RXWAKE
Character Received
URXIFGx
URXIEx
Interrupt Service
Requested
SWRST
PUC
UxRXBUF Read
URXSE
IRQA
SYNC = 1
Clear
Figure 18−12. Receive Interrupt State Diagram
Receive
Character
Completed
Interrupt
Service Started,
GIE = 0
URXIFGx = 0
USPIEx = 0
URXIFGx = 1
USPIEx = 1 and
URXIEx = 1 and
GIE = 1 and
Priority Valid
GIE = 0
Priority
Too
Low
URXIFGx = 0
Wait For Next
Start
USPIEx = 0
SWRST = 1
PUC
USPIEx = 1
URXIEx = 0
SWRST = 1
Receive
Character
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 ...