AT80C51RD2 Atmel Corporation, AT80C51RD2 Datasheet - Page 57

• Manufacturer Part Number: AT80C51RD2
• Manufacturer: Atmel Corporation

Specifications of AT80C51RD2

• Max. Operating Frequency: 60 MHz
• Cpu: 8051-12C
• Max I/o Pins: 32
• Spi: 1
• Uart: 1
• Sram (kbytes): 1.25
• Operating Voltage (vcc): 2.7 to 5.5
• Timers: 4
• Watchdog: Yes

Figure 14-1. Power-down Exit Waveform
Table 14-1.
Note:
4113D–8051–01/09
Power-down
Power-down
Mode
Idle
Idle
1. Port 0 can force a 0 level. A "one" will leave port floating.
State of Ports
XTAL
INT0
INT1
Program Memory
External
External
Active Phase
Internal
Internal
Exit from power-down by reset redefines all the SFRs, exit from power-down by external inter-
rupt does no affect the SFRs.
Exit from power-down by either reset or external interrupt does not affect the internal RAM
content.
Note:
Table 14-1
If idle mode is activated with power-down mode (IDL and PD bits set), the exit sequence is
unchanged, when execution is vectored to interrupt, PD and IDL bits are cleared and idle mode is
not entered.
shows the state of ports during idle and power-down modes.
ALE
1
1
0
0
Power-down Phase
PSEN
1
1
0
0
Port Data
Port Dat
OscillatoR Restart
Floating
Floating
PORT0
(1)
(1)
Port Data
Port Data
Port Data
Port Data
PORT1
Active Phase
Port Data
Port Data
Port Data
Address
PORT2
AT80C51RD2
Port Data
Port Data
Port Data
Port Data
PORT3
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