The routines in this directory supply sufficient support to load a program without using the operating system itself. Either lowcore.o or nullcore.o fill the interrupt vector locations. lowcore.s is easily modified for specific vectors because the vectors are enumerated 1 per line. Nullcore should be used if you want all zeros. Startup.s contains the startup code: the entry point is "start" It sizes up memory, sets the stack pointer pointing to the highest word, and calls the main program. argc will be 1 and agrv will 0; they really shouldn't be used. The load sequence is: ld11 -e start nullcore.o startup.o USERPROG.o libsa.a The library contains a goodie: unbuffered printf for console at location 0177560, or fprintf for a serial line unit at an arbitrary address (address is 1st agument). Initially, interrupts are disabled when the user program is entered. To toggle them from C, call "enable" and "diable". See DOWNLOAD(1) for how to shove the a.out image into the LSI 11.