C8051F120-GQR Silicon Laboratories Inc, C8051F120-GQR Datasheet - Page 309

• Manufacturer Part Number: C8051F120-GQR
• Description: IC 8051 MCU FLASH 128K 100TQFP
• Manufacturer: Silicon Laboratories Inc
• Series: C8051F12xr

Specifications of C8051F120-GQR

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 100MHz
• Connectivity: 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: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 8.25K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 8x8b, 8x12b; D/A 2x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TQFP, 100-VQFP
• Processor Series: C8051F1x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 8.25 KB
• Interface Type: I2C, SMBus, SPI, UART
• Maximum Clock Frequency: 100 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: C8051F120DK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 12 bit, 8 Channel
• On-chip Dac: 12 bit, 2 Channel
• For Use With: 336-1285 - KIT DEV EMBEDDED MODEM336-1284 - KIT DEV EMBEDDED ETHERNET336-1224 - DEVKIT-F120/21/22/23/24/25/26/27
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

23. Timers
Each MCU includes 5 counter/timers: Timer 0 and Timer 1 are 16-bit counter/timers compatible with those
found in the standard 8051. Timer 2, Timer 3, and Timer 4 are 16-bit auto-reload and capture counter/tim-
ers for use with the ADCs, DACs, square-wave generation, or for general-purpose use. These timers can
be used to measure time intervals, count external events and generate periodic interrupt requests. Timer 0
and Timer 1 are nearly identical and have four primary modes of operation. Timer 3 offers 16-bit auto-
reload and capture. Timers 2 and 4 are identical, and offer not only 16-bit auto-reload and capture, but
have the ability to produce a 50% duty-cycle square-wave (toggle output) at an external port pin.
Timers 0 and 1 may be clocked by one of five sources, determined by the Timer Mode Select bits (T1M-
T0M) and the Clock Scale bits (SCA1-SCA0). The Clock Scale bits define a pre-scaled clock by which
Timer 0 and/or Timer 1 may be clocked (See SFR Definition 23.3 for pre-scaled clock selection). Timers 0
and 1 can be configured to use either the pre-scaled clock signal or the system clock directly. Timers 2, 3,
and 4 may be clocked by the system clock, the system clock divided by 12, or the external oscillator clock
source divided by 8.
Timer 0 and Timer 1 may also be operated as counters. When functioning as a counter, a counter/timer
register is incremented on each high-to-low transition at the selected input pin. Events with a frequency of
up to one-fourth the system clock's frequency can be counted. The input signal need not be periodic, but it
should be held at a given logic level for at least two full system clock cycles to ensure the level is properly
sampled.
23.1. Timer 0 and Timer 1
Each timer is implemented as a 16-bit register accessed as two separate 8-bit SFRs: a low byte (TL0 or
TL1) and a high byte (TH0 or TH1). The Counter/Timer Control register (TCON) is used to enable Timer 0
and Timer 1 as well as indicate their status. Timer 0 interrupts can be enabled by setting the ET0 bit in the
IE register (
enabled by setting the ET1 bit in the IE register (
four primary modes selected by setting the Mode Select bits T1M1–T0M0 in the Counter/Timer Mode reg-
ister (TMOD). Both timers can be configured independently.
23.1.1. Mode 0: 13-bit Counter/Timer
Timer 0 and Timer 1 operate as 13-bit counter/timers in Mode 0. The following describes the configuration
and operation of Timer 0. However, both timers operate identically, and Timer 1 is configured in the same
manner as described for Timer 0.
The TH0 register holds the eight MSBs of the 13-bit counter/timer. TL0 holds the five LSBs in bit positions
TL0.4–TL0.0. The three upper bits of TL0 (TL0.7–TL0.5) are indeterminate and should be masked out or
ignored when reading the TL0 register. As the 13-bit timer register increments and overflows from 0x1FFF
(all ones) to 0x0000, the timer overflow flag TF0 (TCON.5) is set and an interrupt will occur if Timer 0 inter-
rupts are enabled.
Section “11.3.5. Interrupt Register Descriptions” on page 157
Two 8-bit counter/timers (Timer 0 only)
8-bit counter/timer with auto-reload
Timer 0 and Timer 1 Modes:
13-bit counter/timer
16-bit counter/timer
Rev. 1.4
Section 11.3.5
16-bit counter/timer with auto-reload
C8051F120/1/2/3/4/5/6/7
Toggle Output (Timer 2 and 4 only)
16-bit counter/timer with capture
Timer 2, 3 and 4 Modes:
). Both counter/timers operate in one of
C8051F130/1/2/3
); Timer 1 interrupts can be
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