AT89C51ED2-RLTUM Atmel, AT89C51ED2-RLTUM Datasheet - Page 31

• Manufacturer Part Number: AT89C51ED2-RLTUM
• Description: IC 8051 MCU FLASH 64K 44VQFP
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C51ED2-RLTUM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 60MHz
• Connectivity: SPI, UART/USART
• Peripherals: POR, PWM, WDT
• Number Of I /o: 34
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Cpu Family: 89C
• Device Core: 8051
• Device Core Size: 8b
• Frequency (max): 40MHz
• Interface Type: SPI/UART
• Total Internal Ram Size: 2KB
• # I/os (max): 34
• 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: VQFP
• Processor Series: AT89x
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 2 KB
• Maximum Clock Frequency: 60 MHz
• Number Of Programmable I/os: 34
• Number Of Timers: 3
• Operating Supply Voltage: 2.7 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Minimum Operating Temperature: - 40 C
• Package: 44VQFP
• Family Name: AT89
• Maximum Speed: 40 MHz
• For Use With: AT89OCD-01 - USB EMULATOR FOR AT8XC51 MCU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Converters: -
• Lead Free Status / Rohs Status: Compliant

12.2
4235K–8051–05/08
Programmable
Clock-output
Figure 12-1. Auto-reload Mode Up/Down Counter (DCEN = 1)
In the clock-out mode, Timer 2 operates as a 50% duty-cycle, programmable clock generator
(See Figure 12-2). The input clock increments TL2 at frequency F
edly counts to overflow from a loaded value. At overflow, the contents of RCAP2H and RCAP2L
registers are loaded into TH2 and TL2. In this mode, Timer 2 overflows do not generate inter-
rupts. The formula gives the clock-out frequency as a function of the system oscillator frequency
and the value in the RCAP2H and RCAP2L registers:
For a 16 MHz system clock, Timer 2 has a programmable frequency range of 61 Hz
(F
(P1.0).
Timer 2 is programmed for the clock-out mode as follows:
Clock O
• Set T2OE bit in T2MOD register.
• Clear C/T2 bit in T2CON register.
• Determine the 16-bit reload value from the formula and enter it in RCAP2H/RCAP2L
• Enter a 16-bit initial value in timer registers TH2/TL2. It can be the same as the reload value
• To start the timer, set TR2 run control bit in T2CON register.
CLK PERIPH
registers.
or a different one depending on the application.
– utFrequency
F
/2
CLK PERIPH
16
)
to 4 MHz (F
=
-------------------------------------------------------------------------------------------- -
4
×
CLK PERIPH
(
65536 RCAP2H RCAP2L
:
6
F
–
/4). The generated clock signal is brought out to T2 pin
CLKPERIPH
(UP COUNTING RELOAD VALUE)
(DOWN COUNTING RELOAD VALUE)
T2
RCAP2L
(8-bit)
(8-bit)
(8-bit)
TL2
FFh
⁄
T2CON
RCAP2H
C/T2
(8-bit)
(8-bit)
TH2
(8-bit)
0
1
FFh
AT89C51RD2/ED2
)
CLK PERIPH
T2CON
TR2
/2. The timer repeat-
T2EX:
If DCEN = 1, 1 = UP
If DCEN = 1, 0 = DOWN
If DCEN = 0, up counting
T2CON
TOGGLE
TF2
T2CON
EXF2
INTERRUPT
TIMER 2
31