t89c51rd2-slscl ATMEL Corporation, t89c51rd2-slscl Datasheet - Page 37

• Manufacturer Part Number: t89c51rd2-slscl
• Description: 0 To 40 Mhz Flash Programmable 8-bit Microcontroller
• Manufacturer: ATMEL Corporation

4243G–8051–05/03
Table 21. PCON Register
PCON - Power Control Register (87h)
Reset Value = 00X1 0000b
Not bit addressable
Power-off flag reset value will be 1 only after a power on (cold reset). A warm reset
doesn’t affect the value of this bit.
Number
SMOD1
Bit
7
6
5
4
3
2
1
0
7
Mnemoni
SMOD1
SMOD0
POF
GF1
GF0
SMOD0
Bit
IDL
PD
c
-
6
Description
Serial port Mode bit 1
Set to select double baud rate in mode 1, 2 or 3.
Serial port Mode bit 0
Clear to select SM0 bit in SCON register.
Set to to select FE bit in SCON register.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Power-Off Flag
Clear to recognize next reset type.
Set by hardware when VCC rises from 0 to its nominal voltage. Can also be set by
software.
General purpose Flag
Cleared by user for general purpose usage.
Set by user for general purpose usage.
General purpose Flag
Cleared by user for general purpose usage.
Set by user for general purpose usage.
Power-Down mode bit
Cleared by hardware when reset occurs.
Set to enter power-down mode.
Idle mode bit
Clear by hardware when interrupt or reset occurs.
Set to enter idle mode.
5
-
POF
4
GF1
3
GF0
2
T89C51RD2
PD
1
IDL
0
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