at89c51rd2-smsum ATMEL Corporation, at89c51rd2-smsum Datasheet - Page 60

• Manufacturer Part Number: at89c51rd2-smsum
• Description: 8-bit Flash Microcontroller
• Manufacturer: ATMEL Corporation

15.1
60
Registers
AT89C51RD2/ED2
Table 15-1.
KBF-Keyboard Flag Register (9Eh)
Reset Value = 0000 0000b
This register is read only access, all flags are automatically cleared by reading the register.
Bit Number
KBF7
7
7
6
5
4
3
2
1
0
Mnemonic
KBF Register
KBF6
KBF7
KBF6
KBF5
KBF4
KBF3
KBF2
KBF1
KBF0
Bit
6
Description
Keyboard line 7 flag
Set by hardware when the Port line 7 detects a programmed level. It generates a
Keyboard interrupt request if the KBKBIE.7 bit in KBIE register is set.
Must be cleared by software.
Keyboard line 6 flag
Set by hardware when the Port line 6 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.6 bit in KBIE register is set.
Must be cleared by software.
Keyboard line 5 flag
Set by hardware when the Port line 5 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.5 bit in KBIE register is set.
Must be cleared by software.
Keyboard line 4 flag
Set by hardware when the Port line 4 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.4 bit in KBIE register is set.
Must be cleared by software.
Keyboard line 3 flag
Set by hardware when the Port line 3 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.3 bit in KBIE register is set.
Must be cleared by software.
Keyboard line 2 flag
Set by hardware when the Port line 2 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.2 bit in KBIE register is set.
Must be cleared by software.
Keyboard line 1 flag
Set by hardware when the Port line 1 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.1 bit in KBIE register is set.
Must be cleared by software.
Keyboard line 0 flag
Set by hardware when the Port line 0 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.0 bit in KBIE register is set.
Must be cleared by software.
KBF5
5
KBF4
4
KBF3
3
KBF2
2
KBF1
1
4235J–8051–01/08
KBF0
0