UPSD3354DV-40U6 Datasheet, PDF (115/272 Pages) STMicroelectronics – fast 8032 MCU with programmable logic

UPSD33xx
Serial UART interfaces
Figure 29. UART mode 1, block diagram
Timer1
overflow
Timer2
overflow
Internal bus
TB8
Write
to
SBUF
÷2
DS
Q
SBUF
TxD
pin
CL
01
SMOD
TCLK
01
Zero detector
Start
Shift Data
Tx Control
÷16
Tx Clock
TI
Send
RCLK
01
Serial
port
interrupt
) _Sample
t(s ^1-to-0
transition
c _detector
÷16
Rx Clock
Start
RI
Load SBUF
Rx Control
1FFh
Shift
du _{Rx detector}
ro _{Input shift register}
te ^{P RxD}
pin
Load
SBUF
Shift
sole _Read
bSBUF
SBUF
- ^O Internal bus
ct(s) Figure 30. UART mode 1, timing diagram
du _{Tx Clock}
ro ^{Write to SBUF}
P _Send
te ^Data
le^Shift
TxD
so ^TI
Ob ^{Rx Clock}
Start Bit
D0
D1
D2
D3
D4
D5
D6
D7 Stop Bit
AI06826
Transmit
RxD
Bit Detector
Sample Times
Start Bit
D0
D1
D2
D3
D4
D5
D6
D7 Stop Bit
Receive
Shift
RI
AI06843
Doc ID 9685 Rev 7
115/272