arch/z80/src/z180 ^^^^^^^^^^^^^^^^^ The arch/z80 directories contain files to support a variety of 8-bit architectures from ZiLOG (and spin-architectures such as the Rabbit2000). The arch/z80/src/z180 sub-directory contains logic unique to the classic Z180 family of chips. Files in this directory include: z180_head.asm This is the main entry point into the Z180 program. This includes the handler for the RESET, power-up interrupt vector and address zero and all RST interrupts. z180_rom.asm Some architectures may have ROM located at address zero. In this case, a special version of the "head" logic must be used. This special "head" file is probably board-specific and, hence, belongs in the board-specific configs/<board-name>/src directory. This file may, however, be used as a model for such a board-specific file. z180_rom.S is enabled by specifying CONFIG_LINKER_ROM_AT_0000 in the configuration file. A board specific version in the configs/<board-name>/src directory can be used by: 1. Define CONFIG_ARCH_HAVEHEAD 2. Add the board-specific head file, say <filename>.asm, to configs/<board-name>/src 3. Add a file called Make.defs in the configs/<board-name>/src directory containing the line: HEAD_ASRC = <file-name>.asm Make.defs This is the standard makefile fragment that must be provided in all chip directories. This fragment identifies the chip-specific file to be used in building libarch. chip.h This is the standard header file that must be provided in all chip directories. z180_initialstate.c, z180_copystate.c, z180_restoreusercontext.asm, and z180_saveusercontext.asm, switch These files implement the Z180 context switching logic z180_schedulesigaction.c and z180_sigdeliver.c These files implement Z180 signal handling.