
68
AT89C51ID2
4289C–8051–11/05
Table 52. IEN1 Register
IEN1 - Interrupt Enable Register (B1h)
Reset Value = XXXX X000b
Bit addressable
76
543
210
-
ESPI
ETWI
EKBD
Bit
Number
Bit
Mnemonic
Description
7-
Reserved
6-
Reserved
5-
Reserved
4-
Reserved
3-
Reserved
2
ESPI
SPI interrupt Enable bit
Cleared to disable SPI interrupt.
Set to enable SPI interrupt.
1ETWI
TWI interrupt Enable bit
Cleared to disable TWI interrupt.
Set to enable TWI interrupt.
0
EKBD
Keyboard interrupt Enable bit
Cleared to disable keyboard interrupt.
Set to enable keyboard interrupt.