ST STM32F0DISCOVERY User manual

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STM32F0DISCOVERY
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May 2012 Doc ID 022910 Rev 2 1/41
UM1525
User manual
STM32F0DISCOVERY
Discovery kit for STM32 F0 microcontrollers
Introduction
The STM32F0DISCOVERY helps you to discover the STM32 F0 Cortex™-M0 features and
to develop your applications easily. It is based on STM32F051R8T6, an STM32 F0 series
32-bit ARM® Cortex™ microcontroller, and includes an ST-LINK/V2 embedded debug tool,
LEDs, push buttons and a prototyping board.
Figure 1. STM32F0DISCOVERY
Table 1. Applicable tools
Type Part number
Evaluation tools STM32F0DISCOVERY
www.st.com

Contents UM1525
2/41 Doc ID 022910 Rev 2
Contents
1 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 Quick start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1 Getting started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 System requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 Development toolchain supporting the STM32F0DISCOVERY . . . . . . . . . 7
2.4 Order code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4 Hardware and layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.1 STM32F051R8T6 microcontroller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.2 Embedded ST-LINK/V2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.2.1 Using ST-LINK/V2 to program/debug the STM32 F0 on board . . . . . . . 15
4.2.2 Using ST-LINK/V2 to program/debug an external STM32 application . . 16
4.3 Power supply and power selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.4 LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.5 Push buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.6 JP2 (Idd) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.7 OSC clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.7.1 OSC clock supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.7.2 OSC 32 KHz clock supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.8 Solder bridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.9 Extension connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5 Connecting modules on the prototyping board . . . . . . . . . . . . . . . . . . 27
5.1 Mikroelektronica accessory boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
5.2 ST MEMS “adapter boards”, standard DIL24 socket . . . . . . . . . . . . . . . . 30
5.3 Arduino shield boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
6 Mechanical drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
7 Electrical schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

UM1525 Contents
Doc ID 022910 Rev 2 3/41
8 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

List of tables UM1525
4/41 Doc ID 022910 Rev 2
List of tables
Table 1. Applicable tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Table 2. ON/OFF conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 3. Jumper states . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 4. Debug connector CN3 (SWD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Table 5. Solder bridge settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 6. MCU pin description versus board function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 7. Connecting using mikroBUS™ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 8. Connecting using IDC10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Table 9. Connecting with a DIL24 board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Table 10. Supported MEMS adapter boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Table 11. Connecting with Arduino shields. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Table 12. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

UM1525 List of figures
Doc ID 022910 Rev 2 5/41
List of figures
Figure 1. STM32F0DISCOVERY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 2. Hardware block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Figure 3. Top layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 4. Bottom layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 5. STM32F051R8T6 package. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 6. STM32F051R8T6 block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 7. Typical configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 8. STM32F0DISCOVERY connections image . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 9. ST-LINK connections image . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 10. Using IDC10 and mikroBUS™ connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Figure 11. DIL24 socket connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 12. Arduino shield board connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 13. STM32F0DISCOVERY mechanical drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Figure 14. STM32F0DISCOVERY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Figure 15. ST-LINK/V2 (SWD only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Figure 16. MCU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Conventions UM1525
6/41 Doc ID 022910 Rev 2
1 Conventions
Tabl e 2 provides the definition of some conventions used in the present document.
Table 2. ON/OFF conventions
Convention Definition
Jumper JP1 ON Jumper fitted
Jumper JP1 OFF Jumper not fitted
Solder bridge SBx ON SBx connections closed by solder
Solder bridge SBx OFF SBx connections left open

UM1525 Quick start
Doc ID 022910 Rev 2 7/41
2 Quick start
The STM32F0DISCOVERY is a low-cost and easy-to-use development kit to quickly
evaluate and start development with an STM32 F0 series microcontroller.
Before installing and using the product, please accept the Evaluation Product License
Agreement from www.st.com/stm32f0discovery.
For more information on the STM32F0DISCOVERY and for demonstration software, visit
www.st.com/stm32f0discovery.
2.1 Getting started
Follow the sequence below to configure the STM32F0DISCOVERY board and launch the
DISCOVER application:
1. Check jumper position on the board, JP2 on, CN2 on (Discovery selected).
2. Connect the STM32F0DISCOVERY board to a PC with a USB cable ‘type A to mini-B’
through USB connector CN1 to power the board. Red LED LD1 (PWR) and LD2 (COM)
light up and green LED LD3 blinks.
3. Press user button B1 (bottom left corner of the board).
4. Observe how the green LED LD3 blinking changes according to USER button B1
clicks.
5. Each click on USER button B1 is confirmed by the blue LED LD4.
6. To study or modify the DISCOVER project related to this demo, visit
www.st.com/stm32f0discovery and follow the tutorial.
7. Discover the STM32F0 features, download and execute programs proposed in the list
of projects.
8. Develop your own application using available examples.
2.2 System requirements
●Windows PC (XP, Vista, 7)
●USB type A to Mini-B USB cable
2.3 Development toolchain supporting the STM32F0DISCOVERY
●Altium®, TASKING™ VX-toolset
●ARM®, Atollic TrueSTUDIO®
●IAR™, EWARM (IAR Embedded Workbench®)
●Keil™, MDK-ARM™
2.4 Order code
To order the STM32F0 Discovery kit, use the order code STM32F0DISCOVERY.

Features UM1525
8/41 Doc ID 022910 Rev 2
3 Features
The STM32F0DISCOVERY kit offers the following features:
●STM32F051R8T6 microcontroller featuring 64 KB Flash, 8 KB RAM in an LQFP64
package
●On-board ST-LINK/V2 with selection mode switch to use the kit as a standalone
ST-LINK/V2 (with SWD connector for programming and debugging)
●Board power supply: through USB bus or from an external 5 V supply voltage
●External application power supply: 3 V and 5 V
●Four LEDs:
– LD1 (red) for 3.3 V power on
– LD2 (red/green) for USB communication
– LD3 (green) for PC9 output
– LD4 (blue) for PC8 output
●Two push buttons (user and reset)
●Extension header for LQFP64 I/Os for quick connection to prototyping board and easy
probing.
●An additional board is provided with the kit which can be connected to the extension
connector for even easier prototyping and probing.
●A large number of free ready-to-run application firmware examples are available on
www.st.com/stm32f0discovery to support quick evaluation and development.

UM1525 Hardware and layout
Doc ID 022910 Rev 2 9/41
4 Hardware and layout
The STM32F0DISCOVERY is designed around the STM32F051R8T6 microcontroller in a
64-pin LQFP package.
Figure 2 illustrates the connections between the STM32F051R8T6 and its peripherals (ST-
LINK/V2, push button, LEDs and connectors).
Figure 3 and Figure 4 help you to locate these features on the STM32F0DISCOVERY.
Figure 2. Hardware block diagram
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Hardware and layout UM1525
10/41 Doc ID 022910 Rev 2
Figure 3. Top layout
MS30024V1
(red/green LED) LD2
COM
CN3
SWD connector
IDD measurement
ST-LINK/V2
B1 user button
B2 reset button
LD1 (red LED)
PWR
CN2
ST-LINK/DISCOVERY
selector
(green LED) LD3
LD4 (blue LED)
STM32F051R8T6
JP2
5V power supply
input output
3V power supply
input output
SB1 (VBAT)
SB3(B1-USER)
SB4 (B2-RESET)
Note: Pin 1 of CN2, CN3, P1 and P2 connectors are identified by a square.

UM1525 Hardware and layout
Doc ID 022910 Rev 2 11/41
Figure 4. Bottom layout
SB6, SB8, SB10, SB12
MS30025V1
SB5, SB7, SB9, SB11
(RESERVED)
(DEFAULT)
SB20, SB21 (X3crystal)
SB14, SB15 (RX, TX)
SB19 (NRST)
SB16, SB17 (X2 crystal)
SB13(STM_RST)
SB22 (T_SWO)
SB18(MCO)

Hardware and layout UM1525
12/41 Doc ID 022910 Rev 2
4.1 STM32F051R8T6 microcontroller
This 32-bit low- and medium-density advanced ARM™ MCU with a high-performance ARM
Cortex™-M0 32-bit RISC core has 64 Kbytes Flash, 8 Kbytes RAM, RTC, timers, ADC,
DAC, comparators and communication interfaces.
Figure 5. STM32F051R8T6 package
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34-&24
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The STM32 F0 delivers 32-bit performance and STM32 DNA essentials into applications
typically addressed by 8- or 16-bit microcontrollers. It benefits from the combination of real-
time performance, low-power operation, advanced architecture and peripherals associated
to the STM32 ecosystem, which has made the STM32 a reference in the market. Now all
this is accessible for cost-sensitive applications. The STM32 F0 offers unparalleled flexibility
and scalability for home entertainment products, appliances, and industrial equipment.
This device provides the following benefits.
●Superior code execution for better performance and excellent code efficiency for
reduced embedded memory usage
●High-performance connectivity and advanced analog peripherals to support a wide
range of applications
●Flexible clock options and low power modes with fast wake-up for low power
consumption
It has the following key features:
●Core and operating conditions
– ARM® Cortex™-M0 0.9 DMIPS/MHz up to 48 MHz
– 1.8/2.0 to 3.6 V supply range
●High-performance connectivity
– 6 Mbit/s USART
– 18 Mbit/s SPI with 4- to 16-bit data frame
– 1 Mbit/s I²C fast-mode plus
–HDMICEC
●Enhanced control
– 1x 16-bit 3-phase PWM motor control timer
– 5x 16-bit PWM timers
– 1x 16-bit basic timer
– 1x 32-bit PWM timer
– 12 MHz I/O toggling

UM1525 Hardware and layout
Doc ID 022910 Rev 2 13/41
Figure 6. STM32F051R8T6 block diagram
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Hardware and layout UM1525
14/41 Doc ID 022910 Rev 2
4.2 Embedded ST-LINK/V2
The ST-LINK/V2 programming and debugging tool is integrated on the
STM32F0DISCOVERY. The embedded ST-LINK/V2 can be used in 2 different ways
according to the jumper states (see Ta bl e 3):
●Program/debug the MCU on board,
●Program/debug an MCU in an external application board using a cable connected to
SWD connector CN3.
The embedded ST-LINK/V2 supports only SWD for STM32 devices. For information about
debugging and programming features refer to user manual UM1075 (ST-LINK/V2 in-circuit
debugger/programmer for STM8 and STM32) which describes in detail all the ST-LINK/V2
features.
Figure 7. Typical configuration
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(ARDWAREREQUIREMENTS
53"CABLETYPE!TOMINI"
COMPUTERWITH7INDOWS806ISTAOR
$EVELOPMENTTOOLCHAIN
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+EIL-$+!2-
Table 3. Jumper states
Jumper state Description
Both CN2 jumpers ON ST-LINK/V2 functions enabled for on board programming (default)
Both CN2 jumpers OFF ST-LINK/V2 functions enabled for application through external CN3
connector (SWD supported)

UM1525 Hardware and layout
Doc ID 022910 Rev 2 15/41
4.2.1 Using ST-LINK/V2 to program/debug the STM32 F0 on board
To program the STM32 F0 on board, simply plug in the two jumpers on CN2, as shown in
Figure 8 in red, but do not use the CN3 connector as that could disturb communication with
the STM32F051R8T6 of the STM32F0DISCOVERY.
Figure 8. STM32F0DISCOVERY connections image

Hardware and layout UM1525
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4.2.2 Using ST-LINK/V2 to program/debug an external STM32 application
It is very easy to use the ST-LINK/V2 to program the STM32 on an external application.
Simply remove the 2 jumpers from CN2 as shown in Figure 9, and connect your application
to the CN3 debug connector according to Table 4.
Note: SB19 and SB22 must be OFF if you use CN3 pin 5 in your external application.
Table 4. Debug connector CN3 (SWD)
Pin CN3 Designation
1 VDD_TARGET VDD from application
2 SWCLK SWD clock
3 GND Ground
4 SWDIO SWD data input/output
5 NRST RESET of target MCU
6 SWO Reserved
Figure 9. ST-LINK connections image

UM1525 Hardware and layout
Doc ID 022910 Rev 2 17/41
4.3 Power supply and power selection
The power supply is provided either by the host PC through the USB cable, or by an external
5V power supply.
The D1 and D2 diodes protect the 5V and 3V pins from external power supplies:
●5V and 3V can be used as output power supplies when another application board is
connected to pins P1 and P2.
In this case, the 5V and 3V pins deliver a 5V or 3V power supply and power
consumption must be lower than 100 mA.
●5V can also be used as input power supplies e.g. when the USB connector is not
connected to the PC.
In this case, the STM32F0DISCOVERY board must be powered by a power supply unit
or by auxiliary equipment complying with standard EN-60950-1: 2006+A11/2009, and
must be Safety Extra Low Voltage (SELV) with limited power capability.
4.4 LEDs
●LD1 PWR: Red LED indicates that the board is powered.
●LD2 COM: Tricolor LED (COM) advises on the communication status as follows:
– Slow blinking Red LED/Off: At power on before USB initialization
– Fast blinking Red LED/Off: After the first correct communication between PC and
STLINK/V2 (enumeration)
– Red LED On: When initialization between PC and ST-LINK/V2 is successfully
finished
– Green LED On: After successful target communication initialization
– Blinking Red/Green LED: During communication with target
– Red LED On: Communication finished and OK
– Orange LED On: Communication failure
●User LD3: Green user LED connected to the I/O PC9 of the STM32F051R8T6.
●User LD4: Blue user LED connected to the I/O PC8 of the STM32F051R8T6.
4.5 Push buttons
●B1 USER: User push button connected to the I/O PA0 of the STM32F051R8T6.
●B2 RESET: Push button used to RESET the STM32F051R8T6.
4.6 JP2 (Idd)
Jumper JP2, labeled Idd, allows the consumption of STM32F051R8T6 to be measured by
removing the jumper and connecting an ammeter.
●Jumper on: STM32F051R8T6 is powered (default).
●Jumper off: an ammeter must be connected to measure the STM32F051R8T6 current,
(if there is no ammeter, the STM32F051R8T6 is not powered).

Hardware and layout UM1525
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4.7 OSC clock
4.7.1 OSC clock supply
PF0 and PF1 can be used as GPIO or as HSE oscillator. By default these I/Os are
configured as GPIO, so SB16 and SB17 are closed, SB18 is open and R22, R23, C13 and
C14 are not populated.
An external HSE clock can be provided to the MCU in three ways:
●MCO from ST-LINK. From MCO of the STM32F103. This frequency cannot be
changed, it is fixed at 8 MHz and connected to PF0-OSC_IN of the STM32F051R8T6.
Configuration needed:
– SB16, SB18 CLOSED
–R22,R23removed
– SB17 OPEN
●Oscillator onboard. From X2 crystal (not provided). For typical frequencies and its
capacitors and resistors, please refer to the STM32F051R8T6 Datasheet.
Configuration needed:
– SB16, SB17 SB18 OPEN
– R22, R23, C13, C14 soldered
●Oscillator from external PF0. From external oscillator through pin 7 of the P1
connector. Configuration needed:
– SB16, SB17 CLOSED
– SB18 OPEN
– R22 and R23 removed
4.7.2 OSC 32 KHz clock supply
PC14 and PC15 can be used as GPIO or as LSE oscillator. By default these I/Os are
configured as GPIO, so SB20 & SB21 are closed and X3, R24, R25 are not populated.
An external LSE clock can be provided to the MCU in two ways:
●Oscillator onboard. From X3 crystal (not provided). Configuration needed:
– SB20, SB21 OPEN
– C15, C16, R24 and R25 soldered.
●Oscillator from external PC14. From external oscillator trough the pin 5 of P1
connector. Configuration needed:
– SB20, SB21 CLOSED
– R24 and R25 removed

UM1525 Hardware and layout
Doc ID 022910 Rev 2 19/41
4.8 Solder bridges
Table 5. Solder bridge settings
Bridge State(1) Description
SB16,17
(X2 crystal)(2)
2. OSC_IN clock comes from MCO if SB18 is ON and SB16,17 are OFF
and comes from X2 if SB18 is OFF and SB16,17 are ON.
OFF X2, C13, C14, R22 and R23 provide a clock. PF0, PF1 are disconnected
from P1.
ON PF0, PF1 are connected to P1 (R22, R23 and SB18 must not be fitted).
SB6,8,10,12 (Default) ON Reserved, do not modify.
SB5,7,9,11 (Reserved) OFF Reserved, do not modify.
SB20,21
(X3 crystal)
OFF X3, C15, C16, R24 and R25 deliver a 32 KHz clock. PC14, PC15 are not
connected to P1.
ON PC14, PC15 are only connected to P1 (R24, R25 must not be fitted).
SB4
(B2-RESET)
ON B2 push button is connected to the NRST pin of the STM32F051R8T6
MCU.
OFF B2 push button is not connected the NRST pin of the STM32F051R8T6
MCU.
SB3
(B1-USER)
ON B1 push button is connected to PA0.
OFF B1 push button is not connected to PA0.
SB1
(VBAT powered from VDD)
ON VBAT is permanently powered from VDD.
OFF VBAT is not powered from VDD but pin3 of P1.
SB14,15
(RX,TX)
OFF Reserved, do not modify.
ON Reserved, do not modify.
SB19
(NRST)
ON NRST signal of the CN3 connector is connected to the NRST pin of the
STM32F051R8T6 MCU.
OFF NRST signal of the CN3 connector is not connected to the NRST pin of the
STM32F051R8T6 MCU.
SB22
(T_SWO)
ON SWO signal of the CN3 connector is connected to PB3.
OFF SWO signal is not connected.
SB13
(STM_RST)
OFF No incidence on STM32F103C8T6 (ST-LINK/V2) NRST signal.
ON STM32F103C8T6 (ST-LINK/V2) NRST signal is connected to GND.
SB2
(BOOT0)
ON BOOT0 signal of the STM32F051R8T6 MCU is held low through a
510 Ohm pull-down resistor.
OFF BOOT0 signal of the STM32F051R8T6 MCU can be set high through a
10 KOhm pull-up resistor R27 to solder.
SB18
(MCO)(2)
ON Provides the 8 MHz for OSC_IN from MCO of STM32F103C8T6.
OFF See SB16, SB17 description.
1. Default SBx state is shown in bold.