Insert the CD or Floppy with the exe file into the computer. Once at the ARC Miltiboot menu select "Run a program" and type cd:\memtest if running from CD, or a:\memtest when running from a floppy.
Detailed descriptions given below may help in advanced cases, but most of the time it's enough just check if errors are absent or present Alternatively, the tool can be started from cmdline ...
I am trying to add "mtest" command, but I get the following error: cmd/mem.c: In function 'do_mem_mtest': cmd/mem.c:875:10: error: 'CONFIG_SYS_MEMTEST_START' undeclared (first use in this function) ...