C8051F046-GQ Silicon Laboratories Inc, C8051F046-GQ Datasheet - Page 277

• Manufacturer Part Number: C8051F046-GQ
• Description: IC 8051 MCU 32K FLASH 100TQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F04xr

Specifications of C8051F046-GQ

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: CAN, EBI/EMI, SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 64
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 4.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TQFP, 100-VQFP
• Processor Series: C8051F0x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 4.25 KB
• Interface Type: CAN, SMBus, SPI, UART
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 64
• Number Of Timers: 5
• Operating Supply Voltage: 2.7 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: C8051F040DK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 13 Channel
• On-chip Dac: 12 bit, 2 Channel
• Package: 100TQFP
• Device Core: 8051
• Family Name: C8051F04x
• Maximum Speed: 25 MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: 336-1211

22. UART1
UART1 is an asynchronous, full duplex serial port offering modes 1 and 3 of the standard 8051 UART.
Enhanced baud rate support allows a wide range of clock sources to generate standard baud rates (details
in
UART1 to start reception of a second incoming data byte before software has finished reading the previous
data byte.
UART1 has two associated SFRs: Serial Control Register 1 (SCON1) and Serial Data Buffer 1 (SBUF1).
The single SBUF1 location provides access to both transmit and receive registers. Reading SBUF1
accesses the buffered Receive register; writing SBUF1 accesses the Transmit register.
With UART1 interrupts enabled, an interrupt is generated each time a transmit is completed (TI1 is set in
SCON1), or a data byte has been received (RI1 is set in SCON1). The UART1 interrupt flags are not
cleared by hardware when the CPU vectors to the interrupt service routine. They must be cleared manually
by software, allowing software to determine the cause of the UART1 interrupt (transmit complete or receive
complete).
Section “22.1. Enhanced Baud Rate Generation” on page
Rate Generator
UART1 Baud
Write to
SBUF1
Figure 22.1. UART1 Block Diagram
Rx Clock
Tx Clock
Stop Bit
Start
Start
SBUF1
Read
SCON1
TB81
D
SET
CLR
Shift
Input Shift Register
Q
Shift
SFR Bus
(RX Latch)
SBUF1
Tx Control
Rx Control
(9 bits)
0x1FF
SFR Bus
Zero Detector
(TX Shift)
SBUF1
RB81
Load SBUF1
Rev. 1.5
Tx IRQ
Rx IRQ
TI1
RI1
SBUF1
Load
Send
C8051F040/1/2/3/4/5/6/7
Data
Interrupt
Serial
Port
278). Received data buffering allows
RX1
TX1
Crossbar
Crossbar
Port I/O
277