Rainbow Electronics AT89C5122 - Manual (Page 185)

185
AT8xC5122/23
4202E–SCR–06/06
Registers
Reset Value = 00X1 0000b
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.
Table 113. Power Control Register - PCON (S:87h)
7 6 5 4 3 2 1 0
SMOD1 SMOD0 - POF GF1 GF0 PD IDL
Bit
Number
Bit
Mnemonic Description
7 SMOD1
Serial port Mode bit 1 for UART
Set to select double baud rate in mode 1,2 or 3
6 SMOD0
Serial port Mode bit 0 for UART
Cleared to select SM0 bit in SCON register
Set to select FE bit in SCON register
5 -
Reserved
The value read from this bit is indeterminate. Do not change this bit.
4 POF
Power-Off Flag (Only for ROM version parts)
Cleared to recognize next reset type
Set by hardware when VCC rises from 0 to its nominal voltage. Can also be set
by software
Warning : in CRAM and FLASH versions, this bit is reserved.
3 GF1
General purpose Flag
Cleared by user for general-purpose usage
Set by user for general-purpose usage
2 GF0
General purpose Flag
Cleared by user for general-purpose usage
Set by user for general-purpose usage
1 PD
Power-Down mode bit
Cleared by hardware when reset occurs
Set to enter power-down mode
0 IDL
Idle mode bit
Cleared by hardware when interrupt or reset occurs
Set to enter idle mode