UPSD3433EB40U6 STMicroelectronics, UPSD3433EB40U6 Datasheet - Page 99

• Manufacturer Part Number: UPSD3433EB40U6
• Description: MCU 8BIT 8032 128KB FLASH 80TQFP
• Manufacturer: STMicroelectronics
• Series: µPSDr

Specifications of UPSD3433EB40U6

• Core Processor: 8032
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, IrDA, SPI, UART/USART, USB
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 46
• Program Memory Size: 160KB (160K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TQFP, 80-VQFP
• For Use With: 497-5518 - EVAL BOARD RFID READER497-5046 - KIT TOOL FOR ST7/UPSD/STR7 MCU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Other names: 497-5660

uPSD34xx
21
Note:
21.1
21.1.1
21.1.2
Serial UART interfaces
uPSD34xx devices provide two standard 8032 UART serial ports.
The operation of the two serial ports are the same and are controlled by two SFRs:
●
●
Each UART has its own data buffer accessed through an SFR listed below:
●
●
When writing SBU0 or SBUF1, the data automatically loads into the associated UART
transmit data register. When reading this SFR, data comes from a different physical register,
which is the receive register of the associated UART.
For simplicity in the remaining UART discussions, the suffix “0” or “1” will be dropped when
referring to SFR registers and bits related to UART0 or UART1, since each UART interface
has identical operation. Example, SBUF0 and SBUF1 will be referred to as just SBUF.
Each UART serial port can be full-duplex, meaning it can transmit and receive
simultaneously. Each UART is also receive-buffered, meaning it can commence reception of
a second byte before a previously received byte has been read from the SBUF Register.
However, if the first byte still has not been read by the time reception of the second byte is
complete, one of the bytes will be lost.
UART operation modes
Each UART can operate in one of four modes, one mode is synchronous, and the others are
asynchronous as shown in
Mode 0
Mode 0 provides asynchronous, half-duplex operation. Serial data is both transmitted, and
received on the RxD pin. The TxD pin outputs a shift clock for both transmit and receive
directions, thus the MCU must be the master. Eight bits are transmitted/received LSB first.
The baud rate is fixed at 1/12 of f
Mode 1
Mode 1 provides standard asynchronous, full-duplex communication using a total of 10 bits
per data byte. Data is transmitted through TxD and received through RxD with: a Start Bit
(logic '0'), eight data bits (LSB first), and a Stop Bit (logic '1'). Upon receive, the eight data
bits go into the SFR SBUF, and the Stop Bit goes into bit RB8 of the SFR SCON. The baud
rate is variable and derived from overflows of Timer 1 or Timer 2.
–
–
SCON0
SCON1
SBUF0 for UART0, address 99h
SBUF1 for UART1, address D9h
The first port, UART0, is connected to pins RxD0 (P3.0) and TxD0 (P3.1)
The second port, UART1 is connected to pins RxD1 (P1.2) and TxD1 (P1.3).
UART1 can optionally be routed to pins P4.2 and P4.3 as described in
Section 17.1.4: Alternate Functions on page
(Table 47 on page
(Table 48 on page
Table 46 on page
101) for UART0
102) for UART1
OSC
.
100.
74.
Serial UART interfaces
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