AT89C51RD2 Atmel Corporation, AT89C51RD2 Datasheet - Page 62

• 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

62
AT89C51RD2/ED2
Table 15-3.
KBLS-Keyboard Level Selector Register (9Ch)
Reset Value = 0000 0000b
Bit Number
KBLS7
7
7
6
5
4
3
2
1
0
Mnemonic
KBLS Register
KBLS6
KBLS7
KBLS6
KBLS5
KBLS4
KBLS3
KBLS2
KBLS1
KBLS0
Bit
6
Description
Keyboard line 7 Level Selection bit
Cleared to enable a low level detection on Port line 7.
Set to enable a high level detection on Port line 7.
Keyboard line 6 Level Selection bit
Cleared to enable a low level detection on Port line 6.
Set to enable a high level detection on Port line 6.
Keyboard line 5 Level Selection bit
Cleared to enable a low level detection on Port line 5.
Set to enable a high level detection on Port line 5.
Keyboard line 4 Level Selection bit
Cleared to enable a low level detection on Port line 4.
Set to enable a high level detection on Port line 4.
Keyboard line 3 Level Selection bit
Cleared to enable a low level detection on Port line 3.
Set to enable a high level detection on Port line 3.
Keyboard line 2 Level Selection bit
Cleared to enable a low level detection on Port line 2.
Set to enable a high level detection on Port line 2.
Keyboard line 1 Level Selection bit
Cleared to enable a low level detection on Port line 1.
Set to enable a high level detection on Port line 1.
Keyboard line 0 Level Selection bit
Cleared to enable a low level detection on Port line 0.
Set to enable a high level detection on Port line 0.
KBLS5
5
KBLS4
4
KBLS3
3
KBLS2
2
KBLS1
1
4235K–8051–05/08
KBLS0
0