Modulator
ACLK
SMCLK
SMCLK
00
01
10
11
UCSSELx
UC0CLK
Prescaler/Divider
Receive Baud-Rate Generator
UC0BRx
16
UCBRFx
4
UCBRSx
8
UCOS16
UCRXERR
Error Flags
Set Flags
UCPE
UCFE
UCOE
UCABEN
Receive Shift Register
Receive Buffer UCAxRXBUF
Receive State Machine
1
0
UCIREN
UCPEN
UCPAR
UCMSB UC7BIT
UCDORM
UCMODEx
2
UCSPB
Set UCBRK
Set UCADDR/UCIDLE
0
1
UCLISTEN
UCAxRXD
1
0
UCIRRXPL
IrDA Decoder
UCIRRXFE
UCIRRXFLx
6
Transmit Buffer UCAxTXBUF
Transmit State Machine
UCTXADDR
UCTXBRK
Transmit Shift Register
UCPEN
UCPAR
UCMSB UC7BIT
UCIREN
UCIRTXPLx
6
0
1
IrDA Encoder
UCAxTXD
Transmit Clock
Receive Clock
BRCLK
UCMODEx
2
UCSPB
UCRXEIE
UCRXBRKIE
Set UCRXIFG
Set UCTXIFG
Set RXIFG
eUSCI_A Introduction – UART Mode
769
SLAU367P – October 2012 – Revised April 2020
Copyright © 2012–2020, Texas Instruments Incorporated
Enhanced Universal Serial Communication Interface (eUSCI) – UART Mode
Figure 30-1. eUSCI_Ax Block Diagram – UART Mode (UCSYNC = 0)