AT89C51RD2 Atmel Corporation, AT89C51RD2 Datasheet - Page 74

• Manufacturer Part Number: AT89C51RD2
• Manufacturer: Atmel Corporation

Specifications of AT89C51RD2

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

74
AT89C51RD2/ED2
Table 17-3.
IEN0 - Interrupt Enable Register (A8h)
Reset Value = 0000 0000b
Bit addressable
Number
EA
Bit
7
7
6
5
4
3
2
1
0
Mnemonic
IENO Register
ET2
ET1
EX1
ET0
EX0
EC
Bit
EA
EC
ES
6
Description
Enable All interrupt bit
Cleared to disable all interrupts.
Set to enable all interrupts.
PCA interrupt enable bit
Cleared to disable.
Set to enable.
Timer 2 overflow interrupt Enable bit
Cleared to disable timer 2 overflow interrupt.
Set to enable timer 2 overflow interrupt.
Serial port Enable bit
Cleared to disable serial port interrupt.
Set to enable serial port interrupt.
Timer 1 overflow interrupt Enable bit
Cleared to disable timer 1 overflow interrupt.
Set to enable timer 1 overflow interrupt.
External interrupt 1 Enable bit
Cleared to disable external interrupt 1.
Set to enable external interrupt 1.
Timer 0 overflow interrupt Enable bit
Cleared to disable timer 0 overflow interrupt.
Set to enable timer 0 overflow interrupt.
External interrupt 0 Enable bit
Cleared to disable external interrupt 0.
Set to enable external interrupt 0.
ET2
5
ES
4
ET1
3
EX1
2
ET0
1
4235K–8051–05/08
EX0
0