Цитата(esaulenka @ Sep 10 2009, 16:08)

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Chapter 8: GPIO
Table 66. GPIO register map (local bus accessible registers - enhanced GPIO features on LPC213x/01 only)
FIOPIN Fast Port Pin value register using FIOMASK.
The current state of digital port pins can be
read from this register, regardless of pin
direction or alternate function selection (as
long as pin is not configured as an input to
ADC). The value read is value of the
physical pins masked by ANDing the
inverted FIOMASK. Writing to this register
affects only port bits enabled by ZEROES in
FIOMASK.
4.3 GPIO port Pin value register (IOPIN, Port 0: IO0PIN - 0xE002 8000 and
Port 1: IO1PIN - 0xE002 8010; FIOPIN, Port 0: FIO0PIN - 0x3FFF C014
and Port 1: FIO1PIN - 0x3FFF C034)
This register provides the value of port pins that are configured to perform only digital
functions. и т. д.
Если этого не достаточно, то я не знаю...