UM10237_2 © NXP B.V. 2008. All rights reserved.
User manual Rev. 02 — 19 December 2008 197 o f 792
NXP Semiconductors UM10237
Chapter 10: LPC24XX General Purpose Input/Output (GPIO)
[1] Reset value reflects the data stored in used bits only. It does not include reserved bits content.
Table 159. Summary of GPIO registers (local bus accessible registers - enhanced GPIO features)
Generic
Name Description Access Reset
value[1] PORTn Register
Address & Name
FIODIR Fast GPIO Port Direction control register. This register
individually controls the direction of each port pin. R/W 0x0 FIO0DIR - 0x3FFF C000
FIO1DIR - 0x3FFF C020
FIO2DIR - 0x3FFF C040
FIO2DIR - 0x3FFF C060
FIO2DIR - 0x3FFF C080
FIOMASK Fast Mask register for port. Writes, sets, clears, and reads to
port (done via writes to FIOPIN, FIOSET, and FIOCLR, and
reads of FIOPIN) alter or return only the bits enabled by zeros
in this register.
R/W 0x0 FIO0MASK - 0x3FFFC010
FIO1MASK - 0x3FFF C030
FIO2MASK - 0x3FFF C050
FIO3MASK - 0x3FFF C070
FIO4MASK - 0x3FFF C090
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 pins are
not configured as an input to ADC). The value read is masked
by ANDing with inverted FIOMASK. Writing to this register
places corresponding values in all bits enabled by zeros in
FIOMASK.
Important: if a FIOPIN register is read, its bit(s) masked with 1
in the FIOMASK register will be set to 0 regardless of the
physical pin state.
R/W 0x0 FIO0PIN - 0x3FFFC014
FIO1PIN - 0x3FFF C034
FIO2PIN - 0x3FFF C054
FIO3PIN - 0x3FFF C074
FIO4PIN - 0x3FFF C094
FIOSET Fast Port Output Set register using FIOMASK. This register
controls the state of output pins. Writing 1s produces highs at
the corresponding port pins. Writing 0s has no effect. Reading
this register returns the current contents of the port output
register. Only bits enabled by 0 in FIOMASK can be altered.
R/W 0x0 FIO0SET - 0x3FFFC018
FIO1SET - 0x3FFF C038
FIO2SET - 0x3FFF C058
FIO3SET - 0x3FFF C078
FIO4SET - 0x3FFF C098
FIOCLR Fast Port Output Clear register using FIOMASK0. This register
controls the state of output pins. Writing 1s produces lows at
the corresponding port pins. Writing 0s has no effect. Only bits
enabled by 0 in FIOMASK0 can be altered.
WO 0x0 FIO0CLR - 0x3FFFC01C
FIO1CLR - 0x3FFF C03C
FIO2CLR - 0x3FFF C05C
FIO3CLR - 0x3FFF C07C
FIO4CLR - 0x3FFF C09C