USCI Registers: I2C Mode
21-27
Universal Serial Communication Interface, I2C Mode
UCBxCTL1, USCI_Bx Control Register 1
7
6
5
4
3
2
1
0
UCSSELx
Unused
UCTR
UCTXNACK
UCTXSTP
UCTXSTT
UCSWRST
rw−0
rw−0
r0
rw−0
rw−0
rw−0
rw−0
rw−1
UCSSELx
Bits
7-6
USCI clock source select. These bits select the BRCLK source clock.
00
UCLKI
01
ACLK
10
SMCLK
11
SMCLK
Unused
Bit 5
Unused
UCTR
Bit 4
Transmitter/Receiver
0
Receiver
1
Transmitter
UCTXNACK
Bit 3
Transmit a NACK. UCTXNACK is automatically cleared after a NACK is
transmitted.
0
Acknowledge normally
1
Generate NACK
UCTXSTP
Bit 2
Transmit STOP condition in master mode. Ignored in slave mode. In
master receiver mode the STOP condition is preceded by a NACK.
UCTXSTP is automatically cleared after STOP is generated.
0
No STOP generated
1
Generate STOP
UCTXSTT
Bit 1
Transmit START condition in master mode. Ignored in slave mode. In
master receiver mode a repeated START condition is preceded by a
NACK. UCTXSTT is automatically cleared after START condition and
address information is transmitted.
Ignored in slave mode.
0
Do not generate START condition
1
Generate START condition
UCSWRST
Bit 0
Software reset enable
0
Disabled. USCI reset released for operation.
1
Enabled. USCI logic held in reset state.
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 ...