begin support for tmp4c123x
tm4c123x: add gpio module
tm4c123x:rom:GPIO: fill out the rest of the functions
tm4c123x:rom:SysCtl: bool is 8bit on ARM
create chip-specific modules and include generic code
tm4c123x:rom:UART: added
add plugin phase for core for macros
fix lpc1343
tm4c123x:rom:USB: added
tm4c123x:rom:Int: added
tm4c123x:rom:UART: fix SpaceAvail
tm4c123x:usb: add USB constants
tm4c123x/target.mk: add stty and cat targets
add more tiva-C test code
Changed to use the AHB for GPIO access.