Boot Control On 144-Pin Package - Philips LPC2119 User Manual

Philips Semiconductors
ARM-based Microcontroller
Table 64: Pin Function Select Register 2 for LPC2292/2294 (PINSEL2 - 0xE002C014)
PINSEL2
24 Controls whether P3.1/A1 is a port pin (0) or an address line (1).
Controls the number of pins among P3.23/A23/XCLK and P3.22:2/A2.22:2 that are address lines:
000 = None
27:25 001 = A3:2 are address lines.
010 = A5:2 are address lines.
011 = A7:2 are address lines.
31:28 Reserved.
Pin Function Select Register Values
The PINSEL registers control the functions of device pins as shown below. Pairs of bits in these registers correspond to specific
device pins.
Table 65: Pin Function Select Register Bits
Pinsel0 and Pinsel1 Values
0 0
0 1
1 0
1 1
The direction control bit in the IO0DIR/IO1DIR register is effective only when the GPIO function is selected for a pin. For other
functions, direction is controlled automatically. Each derivative typically has a different pinout and therefore a different set of
functions possible for each pin. Details for a specific derivative may be found in the appropriate data sheet.

BOOT CONTROL ON 144-PIN PACKAGE

In the 144-pin package only, the state of the BOOT1:0 pins, while RESET is low, controls booting and initial operation. Internal
pullups in the receivers ensure high state if a pin is left unconnected. Board designers can connect weak pulldown resistors
(4.7 kΩ) or transistors that drive low while RESET is low, to these pins to select among the following options:
Table 66: Boot Control on BOOT1:0
P2.27/D27/BOOT1
0
0
1
1
Pin Connect Block
Description
100 = A11:2 are address lines.
101 = A15:2 are address lines.
110 = A19:2 are address lines.
111 = A23:2 are address lines.
Primary (default) function, typically GPIO Port
First alternate function
Second alternate function
Reserved
P2.26/D26/BOOT0
0 8-bit memory on CS0
1 16-bit memory on CS0
0 32-bit memory on CS0
1 Internal Flash Memory
LPC2119/2129/2292/2294
Function
Boot from
105
Preliminary User Manual
Reset Value
BOOT1 during
Reset
000 if
BOOT1:0=11
at Reset, 111
otherwise
-
Value after Reset
00
January 08, 2004