Simulink Debugger

Use Simulink® debugger to trace problems in your model to specific blocks, parameters, or interconnections

The Simulink debugger allows you to run a simulation one method at a time, and examine the results of executing each method. As the model simulates, you can display information on block states, block inputs and outputs, and block method execution within the Simulink Editor. This allows you to pinpoint problems in your model to specific blocks, parameters, or interconnections.

Use the Simulink debugger to:

  • Monitor single block dynamics (for example, output and update) during a single major time step.

  • Look at state of system while executing a major time step.

  • Observe solver dynamics during a single major step.

Simulink also supports debugging with the Simulation Stepper, which lets you step back and forth through your simulation, viewing data and inspecting how and when the system changes states. For information, see How Simulation Stepper Helps With Model Analysis.


sldebug Start simulation in debug mode

Simulink Debugger Commands

ashow Show algebraic loop
atrace Set algebraic loop trace level
bafter Insert breakpoint after specified method
break Insert breakpoint before specified method
bshow Show specified block
clear Clear breakpoints from model
continue Continue simulation
disp Display block's I/O when simulation stops
ebreak Enable (or disable) breakpoint on solver errors
elist List simulation methods in order in which they are executed during simulation
emode Toggle model execution between accelerated and normal mode
etrace Enable or disable method tracing
help Display help for debugger commands
nanbreak Set or clear nonfinite value break mode
next Advance simulation to start of next method at current level in model's execution list
probe I/O and state data for blocks
quit Stop simulation debugger
rbreak Break simulation before solver reset
run Run simulation to completion
slist Sorted list of model blocks
states Current state values
status Debugging options in effect
step Advance simulation by one or more methods
stimes Model sample times
stop Stop simulation
strace Set solver trace level
systems List nonvirtual systems of model
tbreak Set or clear time breakpoint
trace Display block's I/O each time block executes
undisp Remove block from debugger's list of display points
untrace Remove block from debugger's list of trace points
where Display current location of simulation in simulation loop
xbreak Break when debugger encounters step-size-limiting state
zcbreak Toggle breaking at nonsampled zero-crossing events
zclist List blocks containing nonsampled zero crossings

Related Information

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