ST STM32F401 Discovery User manual

October 2013 DocID025194 Rev 1 1/19
UM1671
User manual
Getting started with STM32F401 Discovery
software development tools
Introduction
This document describes the software environment required to build an application around
the STM32F401 Discovery board (32F401CDISCOVERY), and provides some development
recommendations.
It provides guidelines to novice users on how to build and run a sample application, and
allows them to create and build their own application.
This document:
presents the toolchains supporting the STM32 families:
– IAR Embedded Workbench®for ARM (EWARM) by IAR Systems,
– Microcontroller Development Kit for ARM (MDK-ARM) by Keil™,
– TrueSTUDIO®by Atollic;
describes where to find the ST-LINK/V2 driver to be installed before starting coding on
any Integrated Development Environment;
describes step by step how to execute and debug an existing project with one of the
previously presented toolchains;
describes step by step how to create a new project with one of the toolchains from a
dummy project included in the firmware package;
provides helpful information on the advanced debugging capabilities of the Serial Wire
Viewer (SWV) asynchronous trace supported by ST-LINK. This feature is especially
useful when debugging certain tricky problems you may find during application
development.
This user manual cannot cover all the topics relevant to software development
environments, but it demonstrates the first basic steps necessary to get started with the
compilers/debuggers and provides links to the required documents to fully understand every
step.
www.st.com

Contents UM1671
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Contents
1 Getting started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1 System requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 IDEs supporting STM32 families . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.3 ST-LINK/V2 installation and development . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.4 Firmware package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2 Executing and debugging firmware using a software toolchain . . . . . 9
2.1 EWARM toolchain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2 MDK-ARM toolchain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
2.3 TrueSTUDIO toolchain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3 STM32F401 advanced debugging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4 Software toolchains helpful references and links . . . . . . . . . . . . . . . . 17
5 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

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List of tables
Table 1. Toolchains supporting STM32F401 Discovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 2. Links to software toolchains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 3. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

List of figures UM1671
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List of figures
Figure 1. Hardware environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 2. STM32F401 Discovery package content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 3. IAR Embedded Workbench IDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 4. EWARM project successfully compiled. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 5. IAR Download and Debug button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 6. IAR Embedded Workbench debugger screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 7. IAR Go button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 8. uVision4 IDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 9. MDK-ARM project successfully compiled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 10. MDK-ARM Start/Stop Debug Session button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 11. MDK-ARM debugger screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 12. MDK-ARM Run button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 13. TrueSTUDIO workspace launcher dialog box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 14. TrueSTUDIO import source select dialog box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 15. TrueSTUDIO import projects dialog box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 16. TrueSTUDIO project successfully compiled . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 17. TrueSTUDIO debug window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

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1 Getting started
1.1 System requirements
Before running your application, you should:
1. install your preferred Integrated Development Environment (IDE),
2. install the ST-LINK V2 driver from the ST Website,
3. download the STM32F401 Discovery firmware from the ST Website,
4. establish the connection with the STM32F401 Discovery board as follows.
Figure 1. Hardware environment
The above steps will be detailed in the following sections.
To run and develop any firmware application on your STM32F401 Discovery board, the
minimum requirements are as follows:
Windows PC (2000, XP, Vista, 7)
“USB type A to Mini-B” cable, used to power the board (through USB connector CN1)
from host PC and connect to the embedded ST-LINK/V2 for debugging and
programming

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1.2 IDEs supporting STM32 families
STMicroelectronics' STM32 families of 32-bit ARM Cortex-M core-based microcontrollers
are supported by a complete range of software tools. It encompasses traditional integrated
development environments IDEs with C/C++ compilers and debuggers from major 3rd-
parties (free versions up to 64 KB of code, depending on the partner), completed with
innovative tools from STMicroelectronics.
The following table provides some general information about the most popular integrated
development environments, as well as the version supporting officially the STM32F401
product.
Table 1. Toolchains supporting STM32F401 Discovery
Toolchain Company Compiler Version Download link(1)
1. Registration before download is required.
EWARM IAR Systems® IAR C/C++ 6.60.2
and later
www.iar.com/en/Products/IAR-Embedded-
Workbench/ARM/
– 30-day evaluation edition
– KickStart edition (32 Kb limitation for
Cortex M3/M4)
– KickStart edition (16 Kb limitation for
Cortex M0)
MDK-ARM Keil™ ARMCC 4.73
and later
www.keil.com/demo/eval/arm.htm
MDK-Lite (32 Kb code size limitation)
TrueSTUDIO ©Atollic GNUC 4.2
and later
www.atollic.com/index.php/request-eval-
license
– 32 Kb limitation (8 Kb on Cortex-M0 and
Cortex-M1)
– 30 day Professional version (trial)

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1.3 ST-LINK/V2 installation and development
The STM32F401 Discovery board includes an embedded ST-LINK/V2 debug tool interface.
The interface needs an ST-Link/V2-dedicated USB driver to be installed. This driver is
available from the ST Website www.st.com ST-LINK V2 and is supported by the software
toolchains:
IAR™ Embedded Workbench for ARM (EWARM)
The toolchain is installed by default in the C:\Program Files\IAR Systems\Embedded
Workbench x.x directory on the PC’s local hard disk.
After installing EWARM, install the ST-LINK/V2 driver by running ST-Link_V2_USB.exe
from [IAR_INSTALL_DIRECTORY]\Embedded Workbench x.x\arm\drivers\ST-Link
\ST-Link_V2_USBdriver.exe
RealView Microcontroller Development Kit (MDK-ARM)
The toolchain is installed by default in the C:\Keil directory on the PC’s local hard disk;
the installer creates a µVision4 shortcut in the Start menu.
When connecting the ST-LINK/V2 tool, the PC detects new hardware and prompts the
user to install the ST-LINK_V2_USB driver. The “Found New Hardware” Wizard
displays and guides you through the steps required to install the driver from the
recommended location.
Atollic TrueSTUDIO® STM32
The toolchain is installed by default in the C:\Program Files\Atollic directory on the PC’s
local hard disk.
The ST-Link_V2_USB.exe is installed automatically when installing the software
toolchain.
Complementary information on the firmware package content and the STM32F401
Discovery requirements is available in user manual UM1660 Getting started with the
STM32F401 Discovery kit.
Note: The embedded ST-LINK/V2 supports only the SWD interface for STM32 devices.
1.4 Firmware package
The STM32F401 Discovery firmware applications, demonstration and IP examples are
provided in one single package and supplied in one single zip file. The extraction of the zip
file generates a folder named “STM32F401-Discovery_FW_VX.Y.Z” which contains the
following subfolders:

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Figure 2. STM32F401 Discovery package content
Template project: pre-configured project with empty main function to be customized by the
user. This is helpful to start creating your own application based on the peripheral drivers.
Master workspace: collection of all projects available within this firmware package.
Peripheral examples: includes a set of ready-to-run examples for each peripheral.

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2 Executing and debugging firmware using a software
toolchain
This section describes how to compile/link and execute an existing project using the
toolchains.
The steps below can be applied to an already existing example, demonstration or template
project available at STM32F401-Discovery_FW_VX.Y.Z firmware available at
www.st.com/stm32f4-discovery.
First of all, you need to go through the firmware readme.txt file which contains a description
of the firmware and hardware/software requirements.
2.1 EWARM toolchain
1. Open the IAR Embedded Workbench® for ARM (EWARM).
Figure 3 shows the basic names of the windows referred to in this document.
Figure 3. IAR Embedded Workbench IDE
2. In the File menu, select Open and click Workspace to display the Open Workspace
dialog box. Browse to select either an example or demonstration or template
workspace file, and click Open to launch it in the Project window.
3. In the Project menu, select Rebuild All to compile your project.
4. If your project is successfully compiled, the window shown in Figure 4 is displayed.

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Figure 4. EWARM project successfully compiled
If you need to change your project settings (Include and preprocessor defines), simply go
through the project options:
For Include directories
Project>Options…>C/C++ compiler>
For pre-processor defines
Project>Options…C/C++ compiler>pre-processor>
5. In the IAR Embedded Workbench IDE, from the Project menu, select Download and
Debug or, alternatively, click the Download and Debug button in the toolbar, to program
the Flash memory and begin debugging.
Figure 5. IAR Download and Debug button
6. The debugger in the IAR Embedded Workbench can be used to debug source code at
the C and assembly levels, to set breakpoints, to monitor individual variables and to
watch events during the code execution.
Figure 6. IAR Embedded Workbench debugger screen
To run your application, from the Debug menu, select Go. Alternatively, click the Go button
in the toolbar to run your application.

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Figure 7. IAR Go button
2.2 MDK-ARM toolchain
1. Open the Keil MDK-ARM Microcontroller Kit.
Figure 8 shows the basic names of the Keil uVision4 windows referred to in this document.
Figure 8. uVision4 IDE
2. In the Project menu, select Open Project... Browse to select either an example or
demonstration or template project file, and click Open to launch it in the Project
window.
3. In the Project menu, select Rebuild All target files to compile your project.
4. If your project is successfully compiled, the window shown in Figure 9 is displayed.
Figure 9. MDK-ARM project successfully compiled

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If you need to change your project settings (Include and preprocessor defines), simply go
through the project options:
For Include directories
Project>Options for Target > C/C++ > Include Paths
For pre-processor defines
Project>Options for Target > C/C++ > Preprocessor symbols > Define
5. In the MDK-ARM IDE, from the Debug menu, select Start/Stop Debug Session or,
alternatively, click the Start/Stop Debug Session button the in toolbar, to program the
Flash memory and begin debugging.
Figure 10. MDK-ARM Start/Stop Debug Session button
6. The MDK-ARM debugger can be used to debug source code at the C and assembly
levels, to set breakpoints, to monitor individual variables and to watch events during the
code execution.
Figure 11. MDK-ARM debugger screen
To run your application, from the Debug menu, select Run. Alternatively, click the Run
button in the toolbar to run your application.

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Figure 12. MDK-ARM Run button
2.3 TrueSTUDIO toolchain
1. Open the Atollic TrueSTUDIO® for ARM product. The program launches and prompts
for the Workspace location.
Figure 13. TrueSTUDIO workspace launcher dialog box
2. Browse to select a TrueSTUDIO workspace of either an example or demonstration or
template workspace file, and click OK to load it.
3. To load an existing project in the selected workspace, select Import from the File menu
to display the Import dialog box.
4. In the Import window, open General, select Existing Projects into Workspace and click
Next.

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Figure 14. TrueSTUDIO import source select dialog box
5. Click Select root directory; then browse to the TrueSTUDIO workspace folder.
Figure 15. TrueSTUDIO import projects dialog box
6. In the Projects panel, select the project and click Finish.
7. In the Project Explorer, select the project, open the Project menu, and click Build
Project.
8. If your project is successfully compiled, the following messages display on the Console
window.

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Figure 16. TrueSTUDIO project successfully compiled
If you need to change the project settings (Include directories and preprocessor defines),
simply go through Project>Properties, and select C/C++ Build>Settings from the left panel:
For Include directories
C Compiler>Directories>Include path
For pre-processor defines
C Compiler>Symbols> Defined symbols
9. To debug and run the application, select the project in the Project Explorer and press
F11 to start a debug session.
In the Project Explorer, select the project and press F11 to start a debug session (see
Figure 17).
Figure 17. TrueSTUDIO debug window
The debugger in the Atollic TrueSTUDIO can be used to debug source code at the C and
assembly levels, to set breakpoints, to monitor individual variables and to watch events
during the code execution.
To run your application, from the Run menu, select Resume or, alternatively, click the
Resume button in the toolbar.

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3 STM32F401 advanced debugging
The STM32 family using the Cortex-M4 processor includes many interrupts, and it can be
difficult to determine when they are being activated and how often.
The Serial Wire Viewer (SWV) tool of on the STM32F401 family makes this task easy. SWV
displays PC samples, exceptions (including interrupts), data reads and writes, ITM (printf),
CPU counters and a timestamp. This information comes from the ARM CoreSight™ debug
module integrated into the STM32F401 CPU.
SWV does not steal any CPU cycles and is non-intrusive (except for the ITM Debug printf
Viewer).
You have already configured SWV on the template project. This allows:
1. Retargeting printf to the ITM stimulus port(0). This facilitates the display of the debug
messages.
How to use it:
– EWARM: View > Terminal IO
– MDK-ARM: View > Serial Windows Debug (printf) Viewer
– TrueSTUDIO: View > SWV Console
2. Exception trace:
Provides information on the exception:
– Entry: when the exception enters.
– Exit: when the exception exits or returns.
– Return: when all the exceptions have returned to the main XXX
How to use it:
– EWARM: ST-LINK > Interrupt log
– MDK-ARM: View > Trace > Exceptions
– TrueSTUDIO: View > SWV Exception Trace Log
3. Function profiler: shows timing information for the functions in an application
– EWARM: ST-LINK > Function Profiler
– MDK-ARM: View > Analysis Window > Code Coverage
– TrueSTUDIO: View > SWV Statistical Profiling
4. Data Trace Timeline: shows a graphical representation of the data
– EWARM: ST-LINK > Timeline (Data log)
– MDK-ARM: View > Analysis Window > Logic Analyzer
– TrueSTUDIO: View > SWV Data Trace Timeline

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4 Software toolchains helpful references and links
The following table provides useful references about the integrated development
environments described in this document.
Table 2. Links to software toolchains
Toolchain Download link
EWARM www.iar.com/en/Products/IAR-Embedded-Workbench/ARM/
– EWARM_UserGuide
MDK-ARM www.keil.com/demo/eval/arm.htm
www.keil.com/arm/mdk.asp
TrueSTUDIO www.atollic.com/index.php/request-eval-license

Revision history UM1671
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5 Revision history
Table 3. Document revision history
Date Revision Changes
02-Oct-2013 1 Initial release.

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