Phytec phyCORE-LPC2292/94, Hardware Manual

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System Configuration
©
PHYTEC Messtechnik GmbH 2006 L-658e_5
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4 System Configuration
Although most features of the Philips LPC2292/94 microcontroller are
configured and/or programmed during the initialization routine, other
features, which impact program execution, must be configured prior to
initialization via pin termination.
4.1 System Startup Configuration
Following a hardware reset, certain port pins are latched by the
controller to configure chip-level features. The desired port pins can
be connected to a weak pull-down resistor (resulting in logical 0), or
by leaving the connections open (resulting in logical 1). Internal pull-
up resistors ensure a high level if the pin is left unconnected. 4.7 k
Ω
pull-down resistors are recommended, although the resistor value is
also dependent upon the external circuitry connected to the port pins
in question.
Table 36 and Table 37 show the individual port pins used for system
startup configuration, the corresponding pull-down resistor and the
location of the signals on the phyCORE connector:
Boot Device Selection
Configuration D26/BOOT0 via
R203 (X700B43)
D27/BOOT1 via
R204 (X700A44)
/CS0 configured for
32-bit memory
populated
BOOT0 = 0
unpopulated
BOOT1 = 1
/CS0 configured for 16-
bit memory
unpopulated
BOOT0 = 1
populated
BOOT1 = o
/CS0 configured for 8-
bit memory
populated
BOOT0 = 0
populated
BOOT1 = 0
Internal Flash access unpopulated
BOOT0 = 1
unpopulated
BOOT1 = 1
Table 36: System Startup Configuration – Boot Device Selection
Default system startup configuration on the phyCORE-LPC2292/94