AT80C51RD2-SLSUM Atmel, AT80C51RD2-SLSUM Datasheet - Page 19

• Manufacturer Part Number: AT80C51RD2-SLSUM
• Description: MCU, 8BIT, 8051, 5V, SPI, 20MHZ, 44PLCC
• Manufacturer: Atmel

Specifications of AT80C51RD2-SLSUM

• Controller Family/series: (8051) 8052
• No. Of I/o's: 32
• Ram Memory Size: 1280Byte
• Cpu Speed: 40MHz
• No. Of Timers: 3
• No. Of Pwm Channels: 5
• Core Size: 8bit
• Oscillator Type: External Only
• Processor Series: AT80x
• Core: 8051
• Data Bus Width: 8 bit
• Program Memory Type: ROMLess
• Data Ram Size: 1280 B
• Interface Type: UART, SPI
• Maximum Clock Frequency: 60 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: PLCC
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Minimum Operating Temperature: - 40 C
• Cpu Family: AT80
• Device Core: 8051
• Device Core Size: 8b
• Frequency (max): 40MHz
• Program Memory Size: Not Required
• Total Internal Ram Size: 1.25KB
• # I/os (max): 32
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 44
• Package Type: PLCC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

6.2
6.2.1
4188F–8051–01/08
Timer 2
Auto-reload Mode
The timer 2 in the
It is a 16-bit timer/counter: the count is maintained by two eight-bit timer registers, TH2 and TL2,
connected in cascade. It is controlled by T2CON register (See Table 6-2) and T2MOD register
(See Table 6-3). Timer 2 operation is similar to Timer 0 and Timer 1. C/T2 selects F
operation) or external pin T2 (counter operation) as the timer clock input. Setting TR2 allows TL2
to be incremented by the selected input.
Timer 2 has 3 operating modes: capture, autoreload and Baud Rate Generator. These modes
are selected by the combination of RCLK, TCLK and CP/RL2 (T2CON), as described in the
Atmel 8-bit Microcontroller Hardware description.
Refer to the Atmel 8-bit Microcontroller Hardware description for the description of Capture and
Baud Rate Generator Modes.
In
The auto-reload mode configures timer 2 as a 16-bit timer or event counter with automatic
reload. If DCEN bit in T2MOD is cleared, timer 2 behaves as in 80C52 (refer to the Atmel 8-bit
Microcontroller Hardware description). If DCEN bit is set, timer 2 acts as an Up/down
timer/counter as shown in Figure 6-2. In this mode the T2EX pin controls the direction of count.
When T2EX is high, timer 2 counts up. Timer overflow occurs at FFFFh which sets the TF2 flag
and generates an interrupt request. The overflow also causes the 16-bit value in RCAP2H and
RCAP2L registers to be loaded into the timer registers TH2 and TL2.
When T2EX is low, timer 2 counts down. Timer underflow occurs when the count in the timer
registers TH2 and TL2 equals the value stored in RCAP2H and RCAP2L registers. The under-
flow sets TF2 flag and reloads FFFFh into the timer registers.
The EXF2 bit toggles when timer 2 overflows or underflows according to the the direction of the
count. EXF2 does not generate any interrupt. This bit can be used to provide 17-bit resolution.
• Auto-reload mode with up or down counter
• Programmable clock-output
TS80C51RX2
TS80C51RX2
Timer 2 includes the following enhancements:
is compatible with the timer 2 in the 80C52.
AT/TS8xC51Rx2
OSC
/12 (timer
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