C8051F066-GQ Silicon Laboratories Inc, C8051F066-GQ Datasheet - Page 268

• Manufacturer Part Number: C8051F066-GQ
• Description: MCU 8-Bit C8051F06x 8051 CISC 32KB Flash 3.3V 100-Pin TQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F06xr

Specifications of C8051F066-GQ

• Package: 100TQFP
• Device Core: 8051
• Family Name: C8051F06x
• Maximum Speed: 25 MHz
• Operating Supply Voltage: 3.3 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 59
• Interface Type: I2C/SMBus/SPI/UART
• On-chip Adc: 2-chx16-bit
• Number Of Timers: 5
• Ram Size: 4.25 KB
• Program Memory Size: 32 KB
• Program Memory Type: Flash
• Operating Temperature: -40 to 85 °C
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 25MHz
• Connectivity: EBI/EMI, SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 59
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 2x16b
• Oscillator Type: Internal
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 336-1221

C8051F060/1/2/3/4/5/6/7
The baud rate generated in Mode 1 is a function of timer overflow. UART0 can use Timer 1 operating in 8-
Bit Auto-Reload Mode, or Timer 2, 3, or 4 operating in Auto-reload Mode to generate the baud rate (note
that the TX and RX clocks are selected separately). On each timer overflow event (a rollover from all ones
- (0xFF for Timer 1, 0xFFFF for Timer 2, 3, or 4) - to zero) a clock is sent to the baud rate logic.
Timers 1, 2, 3, or 4 are selected as the baud rate source with bits in the SSTA0 register (see Figure 22.9).
The transmit baud rate clock is selected using the S0TCLK1 and S0TCLK0 bits, and the receive baud rate
clock is selected using the S0RCLK1 and S0RCLK0 bits.
When Timer 1 is selected as a baud rate source, the SMOD0 bit (SSTA0.4) selects whether or not to divide
the Timer 1 overflow rate by two. On reset, the SMOD0 bit is logic 0, thus selecting the lower speed baud
rate by default. The SMOD0 bit affects the baud rate generated by Timer 1 as shown in Equation 22.1.
The Timer 1 overflow rate is determined by the Timer 1 clock source (T1CLK) and reload value (TH1). The
frequency of T1CLK is selected as described in
Timer 1 overflow rate is calculated as shown in Equation 22.2.
When Timers 2, 3, or 4 are selected as a baud rate source, the baud rate is generated as shown in
Equation 22.3.
The overflow rate for Timer 2, 3, or 4 is determined by the clock source for the timer (TnCLK) and the 16-
bit reload value stored in the RCAPn register (n = 2, 3, or 4), as shown in Equation 22.4.
268
When SMOD0 = 0:
When SMOD0 = 1:
Timer234_OverflowRate
Mode1_BaudRate
Mode1_BaudRate
Mode1_BaudRate
Equation 22.3. Mode 1 Baud Rate using Timer 2, 3, or 4
Timer1_OverflowRate
Equation 22.1. Mode 1 Baud Rate using Timer 1
Equation 22.4. Timer 2, 3, or 4 Overflow Rate
Equation 22.2. Timer 1 Overflow Rate
=
=
=
1 16
1 32
1 16
Rev. 1.2



Section “24.1. Timer 0 and Timer 1” on page
=
=
TnCLK



T1CLK
Timer234_OverflowRate
Timer1_OverflowRate
Timer1_OverflowRate



65536 RCAPn

256 TH1
–
–


287. The