FAQ

Overview

What can I do with MCU Simulator Online?

MCU Simulator Online provides three main features:

Feature Description
Editor A code editor equipped with basic debugging functions such as watch expressions, local variables, breakpoints, and step execution.
Virtual Board Connected to the simulator, allowing you to input values to pins and check pin outputs via a GUI. Serial communication simulation is also supported.
Current Consumption Graph A high-precision graph that shows changes in peripheral current consumption for each program step.
I don't know how to use it.

You can use the Guided Tour from the Help menu in the header to learn the basics.

How can I try an another project?

Click the Find Project button in the header to switch projects.
The current project will be exported and deleted from the server when you change projects.

The available time has expired, and MCU Simulator Online has ended. Can I continue using it?

Yes, you can continue to use it.
After it ends, when you access MCU Simulator Online again, you can start MCU Simulator Online with the sample you were using previously.

How can I evaluate on an actual board after using MCU Simulator Online?

You can export your project using the Export button in the header.
Then, import the exported file into CS+ or e²studio.

For more details, please refer to the following page.

Are there differences between the simulator and an actual board?

Yes, there are some differences.
Please confirm "Differences between target device and simulator" in the following documents, respectively.

Is there a limit on program execution time in the simulator?

Yes, there is.
When 5 minutes have passed in the target device's time, a notification appears at the bottom right of the screen, and the program execution stops.
After the program stops, you can continue execution by clicking the Run button.

Can I use multiple projects at the same time?

No, only one project can be used at a time.
If you want to use an another project, you can change the project from the Find project button in the header.

What is the difference between the trial version and the regular version?

The trial version can be used without a MyRenesas account.
However, there are the following differences.

Feature Trial Regular
Simulation with Virtual Board
Debugging the project
Edit/Save/Export the project ×
Current consumption measurement ×
Available time 10 min Unlimited (120 min per session)
Available projects 4 All (including code generation projects)

To use all features, please log in with your MyRenesas account before starting.

Create MyRenesas Account

Which browsers are supported?

Please use the latest version of the browsers listed below.

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Editor function

How can I save a file that I modified in the editor?

Changes made in the editor are automatically saved to the server, so no manual saving is required.

How can I add a breakpoint?

Click next to the line number in the editor to add a breakpoint, and a red circle will appear.
You can check the breakpoints set at the bottom of the editor.
Due to compiler optimization, you may not be able to add a breakpoint. In that case, specify the optimization level as 'Debug Priority' in the build settings in the header, rebuild, and then set the breakpoint.

Is there a way to check the value of variables in the source code?

Yes, there is.
By adding watch variables, you can check their values. (*)
Only global variables, CPU registers, and SFRs can be registered. For watch variables such as int type, you can change the notation by pressing the button to the left of the value.
Due to compiler optimization, values may not be retrievable. To retrieve values, you need to set the optimization level to 'Debug Priority' in the build settings in the header and rebuild.

(*) For RL78 projects, you can check values in real time while the program is running. For RA projects, values can only be checked while the program is stopped.

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Virtual Board function

The LED blinking interval differs between the simulator and the actual board. Why is that?

In MCU Simulator Online, the LED blinking interval changes based on the simulator's processing time. Therefore, if the simulator processes faster, the LED blinks faster, and if it processes slower, the LED blinks slower.
By enabling CPU Time on the virtual board and running the program, you can check the elapsed time within the simulator since the program started.

Is there a way to know the elapsed time in the simulator?

Yes, there is.
By enabling CPU Time on the virtual board and running the program, you can check the elapsed time within the simulator since the program started.
When enabled, the simulation speed may slow down depending on the peripherals being simulated and the program's processing.

Can I check the value of the pins connected to virtual components?

Yes, you can.
Switch to the Board screen using the screen switch button in the center of the header, and the Pins area will appear on the right side of the virtual board.
In this area, you can check the status of all pins in the simulator, and by clicking the graph icon on the far right of each pin, you can display a graph that samples the pin status in real time.

Can I input values to pins without using virtual components?

Yes, you can.
Switch to the Board screen using the screen switch button in the center of the header, and the Pins area will appear on the right side of the virtual board.
For pins not connected to virtual components, the pen icon appears on the far right. By clicking the icon, you can specify the following value to input to the pin.

Value Type Description
Digital High or Low
Analog Voltage value
Loopback Loop back another pin's digital output
Can I check the output value of a pin without using virtual components?

Yes, you can.
Switch to the Board screen using the screen switch button in the center of the header, and the Pins area will appear on the right side of the virtual board.
For pins not connected to virtual components, the pen icon appears on the far right. By clicking the icon, you can configure it to check the output value of the pin.(*)

(*) However, the pin must be a digital output pin.

How can I send and receive data via UART communication?

By using the UART Console component, you can simulate UART communication with the MCU.
When you select a UART unit in the UART Config property of the UART Console component, a UART monitor for the selected unit is added below the virtual board. In the UART monitor, you can send and receive strings and hexadecimal data while the program is running.

Can I check the internal registers or memory of an I2C communication component?

Yes, you can.
Some I2C communication components allow viewing internal registers and memory. Components with internal registers display a table icon at the bottom right. Clicking the table icon will show the internal registers and memory.

Do virtual components accurately reproduce the behavior of real components?

No, they do not reproduce it exactly.
Only the minimum behavior necessary to verify the operation of the project is reproduced. Therefore, there are differences compared to real components.

Can the value supplied to the simulator's VDD be changed?

Yes, you can change it.
Select a board component on the virtual board and click the Settings button to display the board settings dialog.
From the board settings dialog, you can change the value entered for VDD.

Can an external clock be input to the simulator?

Yes, you can change it.
Select a board component on the virtual board and click the Settings button to display the board settings dialog.
From the board settings dialog, you can specify the frequency to be used as the external clock.

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Current Consumption Measurement function

Why can't I use the current consumption measurement function?

For some MCUs that do not support the current consumption measurement function, the current consumption graph is not available in MCU Simulator Online.
Also, immediately after starting MCU Simulator Online, the graph will not be displayed because there is no measurement data.

Are there any limitations on current consumption measurement?

Yes, there are.
When the number of current consumption change points exceeds 200,000, a notification appears at the bottom right of the screen, and program execution stops.
After the program stops, you can continue execution by clicking the Run button, but the previous current consumption results will be cleared.

Is the displayed current value guaranteed?

No, the displayed current value is not guaranteed; it is a reference value. It is the current value of a standard sample at 25°C.

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