AT89C51ID2 Atmel Corporation, AT89C51ID2 Datasheet - Page 70

• 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

70
AT89C51ID2
Table 55. IPH1 Register
IPH1 - Interrupt Priority High Register (B3h)
Reset Value = XXXX X000b
Not bit addressable
Number
Bit
7
-
7
6
5
4
3
2
1
0
Mnemonic Description
KBDH
TWIH
SPIH
Bit
6
-
-
-
-
-
-
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
SPI interrupt Priority High bit
SPIH
0
0
1
1
TWI interrupt Priority High bit
TWIH
0
0
1
1
Keyboard interrupt Priority High bit
KB DH
0
0
1
1
5
-
TWILPriority Level
KBDLPriority Level
SPILPriority Level
0 Lowest
1
0
1 Highest
0 Lowest
1
0
1 Highest
0 Lowest
1
0
1 Highest
4
-
3
-
SPIH
2
TWIH
1
4289C–8051–11/05
KBDH
0