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UM10375
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© NXP B.V. 2011. All rights reserved.
User manual
Rev. 3 — 14 June 2011
115 of 368
NXP Semiconductors
UM10375
Chapter 7: LPC13xx I/O configuration
7.4.42 IOCON_PIO_3_3
4:3
MODE
Selects function mode (on-chip pull-up/pull-down resistor
control)
10
0x0
Inactive (no pull-down/pull-up resistor enabled)
0x1
Pull-down resistor enabled
0x2
Pull-up resistor enabled
0x3
Repeater mode
5
HYS
Hysteresis
0
0
Disable
1
Enable
9:6
-
-
Reserved
0011
10
OD
Selects pseudo open-drain mode.
0
0
Standard GPIO output
1
Open-drain output
31:11
-
-
Reserved
-
Table 137. IOCON_PIO1_7 register (IOCON_PIO1_7, address 0x4004 40A8) bit description
Bit
Symbol
Value
Description
Reset
value
Table 138. IOCON_PIO3_3 register (IOCON_PIO3_3, address 0x4004 40AC) bit description
Bit
Symbol
Value
Description
Reset
value
2:0
FUNC
Selects pin function. All other values are reserved.
000
0x0
Selects function PIO3_3.
0x1
Selects function RI (function not available on all parts, must
also be configured in the corresponding IOCON_RI_LOC
register).
4:3
MODE
Selects function mode (on-chip pull-up/pull-down resistor
control)
10
0x0
Inactive (no pull-down/pull-up resistor enabled)
0x1
Pull-down resistor enabled
0x2
Pull-up resistor enabled
0x3
Repeater mode
5
HYS
Hysteresis
0
0
Disable
1
Enable
9:6
-
-
Reserved
0011
10
OD
Selects pseudo open-drain mode.
0
0
Standard GPIO output
1
Open-drain output
31:11
-
-
Reserved
-