UPSD3422_06 Datasheet, PDF (107/293 Pages) STMicroelectronics – Turbo Plus Series Fast Turbo 8032 MCU with USB and Programmable Logic

uPSD34xx
Serial UART interfaces
Figure 33. UART Mode 1, Block Diagram
Timer1
Overflow
÷2
Timer2
Overflow
Write
to
SBUF
TB8
D SQ
CL
Internal Bus
SBUF
01
SMOD
TCLK
01
Zero Detector
Start
Shift Data
Tx Control
÷16
Tx Clock
TI
Send
RCLK
01
Serial
Port
Interrupt
Sample
1-to-0
Transition
Detector
÷16
Rx Clock
Start
RI
Load SBUF
Rx Control
1FFh
Shift
Rx Detector
Input Shift Register
RxD
Pin
Load
SBUF
Shift
Read
SBUF
SBUF
Internal Bus
Figure 34. UART Mode 1, Timing Diagram
Tx Clock
Write to SBUF
Send
Data
Shift
TxD
TI
Start Bit
D0
D1
D2
D3
D4
D5
D6
D7 Stop Bit
Rx Clock
RxD
Bit Detector
Sample Times
Shift
RI
Start Bit
D0
D1
D2
D3
D4
D5
D6
D7 Stop Bit
TxD
Pin
AI06826
Transmit
Receive
AI06843
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