Debugging Baremetal Applications Using nSIM

Building and Debugging Applications

nSIM supports running and debugging applications for all ARC families. Debugging is not supported for ARCv3 families yet.

Building and Running "Hello, World!"

Consider a simple example code (save it as main.c):

#include <stdio.h>

int main()
{
    printf("Hello, World!\n");
    return 0;
}

You need to use -specs=nsim.specs to use input/output features and to pass -on nsim_emt option to nSIM to use ARC GNU input/output protocol:

$ arc-elf32-gcc -mcpu=archs -specs=nsim.specs main.c -o main.elf
$ nsimdrv -tcf $NSIM_HOME/etc/tcf/templates/hs38_full.tcf -on nsim_emt main.elf
Hello, World!

You can use MetaWare's own hostlink protocol for input/output operations by passing -specs=hl.specs to GCC. In this case you don't have to pass any additional options to nSIM:

$ arc-elf32-gcc -mcpu=archs -specs=hl.specs main.c -o main.elf
$ nsimdrv -tcf $NSIM_HOME/etc/tcf/templates/hs38_full.tcf main.elf
Hello, World!

Using nCAM Model and Profiling

You can run nSIM in NCAM mode - Near Cycle-Accurate Mode. This mode activates counters that depend on micro-architectural simulations. It may be a good tool for optimization and exploration. NCAM's model is not cycle-accurate and it's not derived from RTL, but it's much faster than xCAM. If you need a cycle-accurate model then consider using xCAM models.