Dave's unofficial HLASM web page
IBM Mainframe Assembler FAQ and tips. IBM's High Level
Assembler (or HLASM for short) is a user-friendly assembler
that has evolved over the years. It incorporates most of the
SLAC assembler mods and IBM is continuing to enhance it. It
runs on the OS/390 (MVS), VM and VSE operating systems.
SPIM (MIPS R2000/R3000 RISC software simulator)
spim is a self-contained simulator that will run MIPS32 assembly language programs. It reads and executes assembly language programs written for this processor. spim also provides a simple debugger and minimal set of operating system services. spim does not execute binary (compiled) programs.