Philips P89LPC903 - Manual (Page 58)

Philips Semiconductors User’s Manual - Preliminary -
P89LPC901/902/903
POWER MONITORING FUNCTIONS
2003 Dec 8
58
Figure 7-1: Power Control Register (PCON)
PCON
Address: 87h
Not bit addressable
Reset Source(s): Any reset
Reset Value:
00000000B
BIT SYMBOL FUNCTION
PCON.7 SMOD1 Double Baud Rate bit for the serial port (UART) when Timer 1 is used as the baud rate
source. When 1, the Timer 1 overflow rate is supplied to the UART. When 0, the Timer 1
overflow rate is divided by 2 before being supplied to the UART. (See Figure 8-2).
PCON.6 SMOD0 Framing Error Location:
-When 0, bit 7 of SCON is accessed as SM0 for the UART.
-When 1, bit 7 of SCON is accessed as the framing error status (FE) for the UART.
This bit also determines the location of the UART receiver interrupt RI (see description
on RI in Figure 8-3).
PCON.5 BOPD Brownout Detect Power down. When 1, Brownout Detect is powered down and therefore
disabled. When 0, Brownout Detect is enabled. (Note: BOPD must be ’0’ before any
programming or erasing commands can be issued. Otherwise these commands will be
aborted.)
PCON.4 BOI Brownout Detect Interrupt Enable. When 1, Brownout Detection will generate a interrupt .
When 0, Brownout Detection will cause a reset.
PCON.3 GF1 General Purpose Flag 1. May be read or written by user software, but has no effect on
operation.
PCON.2 GF0 General Purpose Flag 0. May be read or written by user software, but has no effect on
operation.
PCON.1-0 PMOD1-PMOD0 Power Reduction Mode (see section "Power Reduction Modes").
7 6 5 4 3 2 1 0
SMOD1 SMOD0 BOPD BOI GF1 GF0 PMOD1 PMOD0