AT89C51RE2 Atmel Corporation, AT89C51RE2 Datasheet - Page 114

• Manufacturer Part Number: AT89C51RE2
• Manufacturer: Atmel Corporation

Specifications of AT89C51RE2

• Flash (kbytes): 128 Kbytes
• Max. Operating Frequency: 60 MHz
• Cpu: 8051-12C
• Max I/o Pins: 34
• Spi: 1
• Uart: 2
• Sram (kbytes): 8.25
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 5.5
• Timers: 4
• Isp: UART/OCD
• Watchdog: Yes

114
AT89C51RE2
Table 84. IEN1 Register
IEN1 - Interrupt Enable Register (B1h)
Reset Value = XXXX 00x0b
Bit addressable
Number
Bit
7
7
6
5
4
3
2
1
0
-
Mnemonic
EKBD
ES_1
ETWI
ESPI
Bit
6
-
-
-
-
-
Description
Reserved
Reserved
Reserved
Reserved
Serial port 1 Enable bit
Cleared to disable serial port interrupt.
Set to enable serial port interrupt.
SPI interrupt Enable bit
Cleared to disable SPI interrupt.
Set to enable SPI interrupt.
TWI interrupt Enable bit
Cleared to disable TWI interrupt.
Set to enable TWI interrupt.
Keyboard interrupt Enable bit
Cleared to disable keyboard interrupt.
Set to enable keyboard interrupt.
5
-
4
-
ES_1
3
ESPI
2
ETWI
1
7663E–8051–10/08
EKBD
0