These LPCOpen definitions are common among platforms and specify how the options the built image will contain. Not all platforms may gracefully support these options. These options may be enabled by adding the definition to the sys_config.h file (See Adding platform definitions using sys_config.h) or by adding the definition to the compiler definition list (see Adding platform definitions using the compiler).

DEBUG_ENABLE
This definition enables debug input and output support via the selected I/O device for a platform with the DEBUGIN, DEBUGOUT, and DEBUGSTR macros. The code that contains this support is platform of the platform/board layer code. For supported platforms, this is usually a UART selected with the DEBUG_UART definition. Selecting this option may add considerable size and output delay to the final image. Support for this is part of the board layer code.

DEBUG_UART
This definition selects the UART used for DEBUG IO when the DEBUG_ENABLE definition is enabled. DEBUGIN, DEBUGOUT, and DEBUGSTR macros are routed via the UART selected with this definition. Support for this is part of the board layer code.
Example:

#define DEBUG_UART LPC_UART0