Getting Started with nSIM

Warning

Eclipse IDE for ARCompact targets does not support selecting a value for -specs= option in project's configuration menu. By default, it's not passed to the linker and input/output capabilities are not available. Consider passing -specs=nsim.specs through ARC GNU Linker field of project's configuration dialog (C/C++ Build -> Settings -> Top Settings -> ARC GNU Linker).

Prerequisites

You should have nSIM installed on your computer. You also might need to set environment variable LM_LICENSE_FILE=<your_license> in case if you have full nSIM version. Otherwise you will get licensing failure.

Creating the Project

Select File → New → Project.. and choose C Project. A list of ARC projects will appear. Choose Hello World C Project from the ARC Baremetal Application group. Also, choose GNU Toolchain for ARC HS toolchain.

After creating the project, a simple "Hello, World!" program will be created:

/* Print a greeting on UART output and exit. */

#include <stdio.h>

int main(int argc, char *argv[])
{
    printf("Hello, World!\n\r");
    return 0;
}

Building the Project

Do right click on a project in Project Explorer ans choose Build Project. The project will be built with this output:

make all 
'Building file: ../src/nsim_hello_hs.c'
'Invoking: ARC GNU C Compiler'
C:\arc_gnu\bin\arc-elf32-gcc.exe -mcpu=hs -O0 -g3 -Wall -c -fmessage-length=0 -gdwarf-2 -Wa,-adhlns="src/nsim_hello_hs.o.lst" -MMD -MP -MF"src/nsim_hello_hs.d" -MT"src/nsim_hello_hs.o" -o "src/nsim_hello_hs.o" "../src/nsim_hello_hs.c"
'Finished building: ../src/nsim_hello_hs.c'
' '
'Building target: nsim_hello_hs.elf'
'Invoking: ARC GNU C Linker'
C:\arc_gnu\bin\arc-elf32-gcc.exe -mcpu=hs --specs=nsim.specs -Wl,-Map,nsim_hello_hs.map -o "nsim_hello_hs.elf"  ./src/nsim_hello_hs.o 
'Finished building target: nsim_hello_hs.elf'
' '
'Invoking: ARC GNU Print Size'
C:\arc_gnu\bin\arc-elf32-size.exe  --format=berkeley nsim_hello_hs.elf
   text    data     bss     dec     hex filename
  41088    1724     792   43604    aa54 nsim_hello_hs.elf
'Finished building: nsim_hello_hs.siz'
' '

Creating a Debug Configuration

Do right click on projects's name in Project Explorer and choose Debug As → Debug Configurations.... Then do right click on ARC C/C++ application and choose New Configuration. Here is a main window of the debug configuration:

Ensure that a correct project and binary are selected. Navigate to Main tab and Gdbserver Settings inner tab:

Choose nSIM as ARC GDB Server. Unselect Use nSIM properties file? and select hs48_full.tcf TCF file from nSIM installation.

Navigate to Terminal inner tab of Main tab and unselect Launch Terminal checkbox.

Debugging the Project

Open the debug configuration in Debug Configurations windows and click on Debug button. The Debug perspective will be opened:

Use Step Over button to step over printf function. You can observe output in Console tab:

Using Big Endian Configuration

If you use the big endian toolchain and want to debug the application using nSIM then you need to create a corresponding TCF file manually since there are no TCF files for big endian targets.

For example, if you want to use hs48_full.tcf TCF file then duplicate it with name hs48_full_big.tcf, find this string in it:

nsim_isa_big_endian=0

and change it to this line:

nsim_isa_big_endian=1

Now you can use this TCF file for running big endian applications on nSIM.