
SMSC LPC47B27x
- 150 -
Rev. 08-10-04
DATASHEET
NAME
REG OFFSET
(hex)
5D
(R/W)
DESCRIPTION
LED1
Default = 0x00
on VTR POR
LED1
Bit[1:0] LED1 Control
00=off
01=blink at 1Hz rate with a 50% duty cycle (0.5 sec on, 0.5
sec off)
10=Blink at HZ rate with a 25% duty cycle (0.5 sec on, 1.5
sec off)
11=on
Bits[7:2] Reserved
LED2
Bit[1:0] LED2 Control
00=off
01=blink at 1Hz rate with a 50% duty cycle (0.5 sec on, 0.5
sec off)
10=Blink at HZ rate with a 25% duty cycle (0.5 sec on, 1.5
sec off)
11=on
Bits[7:2] Reserved
Keyboard Scan Code
Bit[0] LSB of Scan Code
. . .
. . .
. . .
Bit[7] MSB of Scan Code
Reserved – reads return 0
LED2
Default = 0x00
on VTR POR
5E
(R/W)
Keyboard Scan
Code
Default = 0x00
on VTR POR
N/A
5F
(R/W)
60-7F
(R)
User Note:
When selecting an alternate function for a GPIO pin, all bits in the GPIO register must
be properly programmed, including in/out, polarity and output type. The polarity bit
does not affect the DDRC function or the either edge triggered interrupt functions.
If this pin is used for Ring Indicator wakeup, either the nRI2 event can be enabled via
bit 1 in the PME_EN1 register or the GP50 PME event can be enabled via bit 0 in the
PME_EN5 register.
If CIR wakeup is to be used with this pin, enable CIR via bit 0 in the PME_EN1
register, do not enable the GP52 PME event via bit 2 in the PME_EN5 register.
In order to use the P12, P16 and P17 functions, the corresponding GPIO must be
programmed for output, non-invert, and push-pull output type.
User Note 1:
User Note 2:
User Note 3:
Note 1: If the EETI function is selected for this GPIO then both a high-to-low and a low-to-high edge
will set the PME, SMI and MSC status bits
Note 2: The IRTX2 function can be used on this pin if the IR Location Mux bit in the Serial Port 2 IR
Option register is set
Note 3: The IR signal on RXD2 may affect both the GP52 PME status bit (bit 2 of PME_STS5) and the
CIR PME status bit (bit 0 of PME_STS1). These two events are enabled independently of
each other via their associated status bits
Note 4: These pins default to an output and LOW on VCC POR and Hard Reset.
Note 5: If the FDC function is selected on this pin (nMTR1, nDS1, DRVDEN0, DRVDEN1) then bit 6
of the FDD Mode Register (Configuration Register 0xF0 in Logical Device 0) will override bit 7
in the GPIO Control Register. Bit 7 of the FDD Mode Register will also affect the pin if the
FDC function is selected.
Note 6: The nIO_SMI pin is inactive when the internal group SMI signal is inactive and when the SMI
enable bit (EN_SMI, bit 7 of the SMI_EN2 register) is ‘0’. When the output buffer type is OD,
nIO_SMI pin is floating when inactive; when the output buffer type is push-pull, the nIO_SMI
pin is high when inactive.
Note 7: Bits 2 and 3 of the PME_STS4 and SMI_STS4 registers, and bit 3 of the PME_STS5 register
may be set on a VCC POR. If GP32, GP33 and GP53 are configured as input, then their
corresponding PME and SMI status bits will be set on a VCC POR. These GPIOs cannot be
used for PME wakeup when the part is under VTR power (VCC=0).
Note 8. This GPIO defaults to a push-pull output following a VTR POR.