Philips 8-bit microcontroller with two-clock 80C51 core UM10109 ユーザーズマニュアル

 

© Koninklijke Philips Electronics N.V. 2005. All rights reserved.

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Cannot be used with operation above 12 MHz as this requires V

DD

 of 3.0 V or above.

The Power-On Detect has a function similar to the Brownout Detect, but is designed to 
work as power initially comes up, before the power supply voltage reaches a level where 
the Brownout Detect can function. The POF flag (RSTSRC.4) is set to indicate an initial 
power-on condition. The POF flag will remain set until cleared by software by writing a 
logic 0 to the bit. Note that if BOE (UCFG1.5) is programmed, BOF (RSTSRC.5) will be 
set when POF is set. If BOE is unprogrammed, BOF is meaningless.

The P89LPC932A1 supports three different power reduction modes as determined by 
SFR bits PCON[1:0] (see 

0 (erased)

XX

X

X

X

X

Brownout disabled. V

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operating range is 2.4 V to 3.6 V.

1(program
med)

11 (total 
power-down)

X

X

X

X

≠ 11 (any mode 
other than total 
power-down)

1 (brownout 
detect 
power-down)

X

X

X

Brownout disabled. V

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operating range is 2.4 V to 3.6 V. 
However, BOPD is default to 
logic 0 upon power-up.

0 (brownout 
detect active)

0 (brownout 
detect 
generates 
reset)

X

X

Brownout reset enabled. V

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operating range is 2.7 V to 3.6 V. 
Upon a brownout reset, BOF 
(RSTSRC.5) will be set to 
indicate the reset source. BOF 
can be cleared by writing a 
logic 0 to the bit.

1 (brownout 
detect 
generates an 
interrupt)

1 (enable 
brownout 
interrupt)

1 (global 
interrupt 
enable)

Brownout interrupt enabled. V

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operating range is 2.7 V to 3.6 V. 
Upon a brownout interrupt, BOF 
(RSTSRC.5) will be set. BOF can 
be cleared by writing a logic 0 to 
the bit.

0

X

Both brownout reset and 
interrupt disabled. V

DD

 operating 

range is 2.4 V to 3.6 V. However, 
BOF (RSTSRC.5) will be set 
when V

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 falls to the Brownout 

Detection trip point. BOF can be 
cleared by writing a logic 0 to the 
bit.

X

0