C8051F018-GQ Silicon Laboratories Inc, C8051F018-GQ Datasheet - Page 114

• Manufacturer Part Number: C8051F018-GQ
• Description: IC 8051 MCU 16K FLASH 64TQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F018r

Specifications of C8051F018-GQ

• Program Memory Type: FLASH
• Program Memory Size: 16KB (16K x 8)
• Package / Case: 64-TQFP, 64-VQFP
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Number Of I /o: 32
• Ram Size: 1.25K x 8
• Voltage - Supply (vcc/vdd): 2.8 V ~ 3.6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: C8051F0x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 1.25 KB
• Interface Type: I2C/SMBus/SPI/UART
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 4
• Operating Supply Voltage: 2.8 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: C8051F005DK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1197

16.1.
The UART provides four operating modes (one synchronous and three asynchronous) selected by setting
configuration bits in the SCON register. These four modes offer different baud rates and communication protocols.
The four modes are summarized in Table 16.1 below. Detailed descriptions follow.
16.1.1. Mode 0: Synchronous Mode
Mode 0 provides synchronous, half-duplex communication. Serial data is transmitted and received on the RX pin.
The TX pin provides the shift clock for both transmit and receive. The MCU must be the master since it generates
the shift clock for transmission in both directions (see the interconnect diagram in Figure 16.2).
Eight data bits are transmitted/received, LSB first (see the timing diagram in Figure 16.3). Data transmission begins
when an instruction writes a data byte to the SBUF register. The TI Transmit Interrupt Flag (SCON.1) is set at the
end of the eighth bit time. Data reception begins when the REN Receive Enable bit (SCON.4) is set to logic 1 and
the RI Receive Interrupt Flag (SCON.0) is cleared. One cycle after the eighth bit is shifted in, the RI flag is set and
reception stops until software clears the RI bit. An interrupt will occur if enabled when either TI or RI is set.
The Mode 0 baud rate is the system clock frequency divided by twelve. RX is forced to open-drain in mode 0, and
an external pull-up will typically be required.
Mode
0
1
2
3
UART Operational Modes
RX (data out)
Synchronization
RX (data in)
Asynchronous
Asynchronous
Asynchronous
TX (clk out)
TX (clk out)
Synchronous
C8051Fxxx
Figure 16.3. UART Mode 0 Timing Diagram
Figure 16.2. UART Mode 0 Interconnect
D0
Timer 1 or Timer 2 Overflow
Timer 1 or Timer 2 Overflow
SYSCLK/32 or SYSCLK/64
D0
RX
Table 16.1. UART Modes
TX
D1
SYSCLK/12
Baud Clock
D1
MODE 0 TRANSMIT
MODE 0 RECEIVE
Rev. 1.2
D2
D2
D3
D3
CLK
DATA
D4
8 Extra Outputs
D4
Data Bits
D5
8
8
9
9
D5
Reg.
Shift
D6
D6
Start/Stop Bits
1 Start, 1 Stop
1 Start, 1 Stop
1 Start, 1 Stop
C8051F018
C8051F019
None
D7
D7
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