AT89C51ID2 Atmel Corporation, AT89C51ID2 Datasheet - Page 20

• Manufacturer Part Number: AT89C51ID2
• Manufacturer: Atmel Corporation

Specifications of AT89C51ID2

• Flash (kbytes): 64 Kbytes
• Max. Operating Frequency: 60 MHz
• Cpu: 8051-12C
• Max I/o Pins: 32
• Spi: 1
• Twi (i2c): 1
• Uart: 1
• Sram (kbytes): 2
• Eeprom (bytes): 2048
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 5.5
• Timers: 4
• Isp: UART
• Watchdog: Yes

Timer 0: Clock Inputs
4289C–8051–11/05
Note:
SCLKT0 = 0: Timer 0 uses the standard T0 pin as clock input (Standard mode)
SCLKT0 = 1: Timer 0 uses the special Sub Clock as clock input, this feature can be use
as periodic interrupt for time clock.
Figure 1. Timer 0: Clock Inputs
(AT 8xC51Ix2 only)
–
FCLK PERIPH
F
In X2 Mode:
In X1 Mode:
The SCLKT0 bit in OSCCON register allows to select Timer 0 Subsidiary clock.
Sub Clock
CLK CPU
T0 pin
INT0
TR0
Gate
and F
OSCCON
SCLKT0
CLK PERIPH
F
F
1
0
:6
CPU
CPU
=
=
F
F
CLKPERIPH
CLKPERIPH
, for CKRL≠0xFF
TMOD
C/T
1
0
=
=
--------------------------------------------- -
2
--------------------------------------------- -
4
×
×
Control
(
(
255 CKRL
255 CKRL
F
F
OSCA
OSCA
–
–
Timer 0
)
)
AT89C51ID2
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