OLIMEX STM32-H405 User manual

STM32-H405 development board
USER’S MANUAL
Revision B, April 2016
Designed by OLIMEX Ltd, 2015
All boards produced by Olimex LTD are ROHS compliant

OLIMEX© 016 STM3 -H405 user's manual
D SCLA MER
© 016 Olimex Ltd. Olimex®, logo and combinations thereof, are registered trademarks of Olimex Ltd. Other product
names may be trademarks of others and the rights belong to their respective owners.
he information in this document is provided in connection with Olimex products. No license, express or implied
or otherwise, to any intellectual property right is granted by this document or in connection with the sale of
Olimex products.
The hardware design of STM3 -H405 development board is considered propriety. The board's schematics are available
in pdf format. The original schematic and design files are not available to the public.
The part of the software written by Olimex is released under GPL. However, note that the examples that we distribute
are based on the libraries and projects released by IAR Systems. Make sure that you are acquainted with the license
agreement of IAR Embedded Workbench before using, publishing, or distributing any code based on the software
released by Olimex.
It is possible that the pictures in this manual differ from the actual appearance of the latest revision of the board.
The product described in this document is subject to continuous development and improvements. All particulars of the
product and its use contained in this document are given by OLIMEX in good faith. However all warranties implied or
expressed including but not limited to implied warranties of merchantability or fitness for purpose are excluded. This
document is intended only to assist the reader in the use of the product. OLIMEX Ltd. shall not be liable for any loss or
damage arising from the use of any information in this document or any error or omission in such information or any
incorrect use of the product.
This evaluation board/kit is intended for use for engineering development, demonstration, or evaluation purposes only
and is not considered by OLIMEX to be a finished end-product fit for general consumer use. Persons handling the
product must have electronics training and observe good engineering practice standards. As such, the goods being
provided are not intended to be complete in terms of required design-, marketing-, and/or manufacturing-related
protective considerations, including product safety and environmental measures typically found in end products that
incorporate such semiconductor components or circuit boards.
Olimex currently deals with a variety of customers for products, and therefore our arrangement with the user is not
exclusive. Olimex assumes no liability for applications assistance, customer product design, software performance, or
infringement of patents or services described herein.
HERE IS NO WARRAN Y FOR HE DESIGN MA ERIALS AND HE COMPONEN S
USED O CREA E S M32-H405. HEY ARE CONSIDERED SUI ABLE ONLY FOR
S M32-H405.
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OLIMEX© 016 STM3 -H405 user's manual
Table of Contents
DISCLAIMER ......................................................................................................................................
CHAPTER 1 OVERVIEW ................................................................................................................... 5
1. Introduction to the chapter ........................................................................................................... 5
1.1 Features ...................................................................................................................................... 5
1. Target market and purpose of the board ..................................................................................... 6
1.3 Similar boards ............................................................................................................................ 6
1.4 Document Organization ............................................................................................................. 6
CHAPTER : BOARD DESCRIPTION .............................................................................................. 7
.1 Layout (top view) ....................................................................................................................... 7
. Layout (bottom view) ................................................................................................................ 8
.3 EXT pinout (bottom view) ......................................................................................................... 9
CHAPTER 3 SETTING UP THE STM3 -H405 BOARD ................................................................ 10
3. Introduction to the chapter ......................................................................................................... 10
3.1 Electrostatic warning ............................................................................................................... 10
3. Requirements ........................................................................................................................... 10
3. .1 Hardware requirements: ................................................................................................... 10
3. . Software requirements: .................................................................................................... 11
3.3 Powering the board .................................................................................................................. 1
3.4 Programming the board ........................................................................................................... 1
3.4.1 Using JTAG debugger ...................................................................................................... 1
3.4. Using USB cable .............................................................................................................. 1
3.5 Prebuilt software ...................................................................................................................... 13
CHAPTER 4 THE STM3 F405 MICROCONTROLLER ................................................................ 14
4. Introduction to the chapter ......................................................................................................... 14
4.1 The STM3 F405RG features ................................................................................................... 14
CHAPTER 5 CONTROL CIRCUITY AND HARDWARE MODULES .......................................... 16
5. Introduction to the chapter ......................................................................................................... 16
5.1 Reset ......................................................................................................................................... 16
5. Clocks ...................................................................................................................................... 16
5.3 Power supply circuit ................................................................................................................ 16
CHAPTER 6 CONNECTORS AND PINOUT .................................................................................. 17
6. Introduction to the chapter ......................................................................................................... 17
6.1 USB connector ......................................................................................................................... 17
6. JTAG/SWD debug connector .................................................................................................. 18
6.3 EXT connectors ....................................................................................................................... 19
6.3.1 EXT1 header .................................................................................................................... 19
6.3. EXT header .................................................................................................................... 0
6.4 Jumper description ................................................................................................................... 0
6.4.1 BOOT memory select jumpers ......................................................................................... 0
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6.4. R-T jumper ....................................................................................................................... 1
6.4.3 VBAT signal and jumper .................................................................................................. 1
6.4.4 LED_E ............................................................................................................................. 1
6.4.5 USBP_E ........................................................................................................................... 1
6.5 Additional hardware components ............................................................................................
CHAPTER 7 BLOCK DIAGRAM AND MEMORY ........................................................................ 3
7. Introduction to the chapter ......................................................................................................... 3
7.1 Processor family block diagram .............................................................................................. 3
7. Physical memory map .............................................................................................................. 4
CHAPTER 8 SCHEMATICS ............................................................................................................. 5
8. Introduction to the chapter ......................................................................................................... 5
8.1 Eagle schematic ....................................................................................................................... 5
8. Physical dimensions ................................................................................................................. 7
CHAPTER 9 REVISION HISTORY AND SUPPORT ...................................................................... 8
9. Introduction to the chapter ......................................................................................................... 8
9.1 Document revision ................................................................................................................... 8
9. Board revision .......................................................................................................................... 8
9.3 Useful web links and purchase codes ...................................................................................... 9
9.4 Product support ........................................................................................................................ 30
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OLIMEX© 016 STM3 -H405 user's manual
CHAPTER 1 OVERV EW
1. ntroduction to the chapter
Thank you for choosing this general-purpose development board designed and assembled by
Olimex! This document provides a user’s guide for the Olimex STM3 -H405 board. As an
overview, this chapter gives the scope of this document and lists the board’s features. A comparison
between boards similar to STM3 -H405 is presented. The document’s organization is then detailed.
The STM3 -H405 development board enables code development of applications running on the
microcontroller STM3 F405RG, manufactured by STMicroelectronics.
STM3 -H405 board is an entry level development board for the new ARM Cortex M4 family of
devices produced by STMicroelectronics Inc. With STM3 -H405 you can explore the features of
STM3 family on budged, the board has everything necessary to build simple applications: USB
port where power is taken and power supply circuit, reset and oscillator circuits, JTAG port for
programming and debugging, programmable LED and programmable button.
Although a very simple board, it is sufficient enough for building USB applications like PC mouse,
USB mass storage device, USB audio class device, USB to virtual RS 3 port. There are plenty of
GPIOs on the extension headers which can be used to connect your additional circuits.
1.1 Features
The board has the following list of features:
•MCU: STM3 F405RG ARM Cortex M4 in LQFP64 pacakge that operates up to 168 Mhz;
with 10 4KB flash memory; (19 +4)kB SRAM; ×USB; ×CAN; x I C; 3×1 -bit
ADC×16 channels; ×1 -bit DAC; ×UART; 3×SPI; 17 timers; with up to 51 GPIOs
•Standard JTAG connector with ARM ×10 pin layout for programming/debugging with
ARM-JTAG
•USB type B connector
•User button
•RESET button
•User LED
•Power supply LED
•On-board voltage regulator 3.3V with up to 800mA current
•Single power supply: takes power from USB port or extension connector pin
•8 Mhz crystal oscillator
•3 768 Hz crystal and RTC backup battery connector
•Extension headers with 0.1" step for all uC ports
•PCB: FR-4, 1.5 mm (0,06 ")
•Dimensions: (61×34)mm ~ ( .4×1.3)"
•Distance between the ext connectors: 5.4mm ~ 1"
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OLIMEX© 016 STM3 -H405 user's manual
1.2 Target market and purpose of the board
STM3 -H405 is a development board featuring a ARM Cortex-M4 microcontroller. The board can
be powered by a number of different sources. It can be programmed with a debugger via JTAG or
SWD, or alternatively with a cable via USB. The board has a lot of GPIO pins exposed.
The board is suitable for numerous tasks and situations. The power of ARM and the creativity of
OLIMEX come at the best price and the well-known quality.
Every ARM enthusiast would see STM3 -H405 as an interesting bargain and quite capable board
for its low price.
1.3 Similar boards
The STM3 H405RG microcontroller is also present in two other Olimex-made boards – STM3 -
P405 and STM3 -405STK. Both boards have more built-in peripherals compared to STM3 -H405.
STM3 -P405 has MMC card interface with connector, UEXT connector, CAN interface with
connector, UART interface with DE-9 connector, built-in power barrel jack, and a small prototype
area.
STM3 -405STK has micro SD card interface with connector, mini USB, 84x48 BW display,
microphone input with connector; headphone output with connector, UEXT connector. The board
can be powered by a 1.5V AA battery – there is a battery holder provided.
Another board, quite similar to STM3 -H405, is STM3 -H103; the board designs are almost
identical – the main difference is that STM3 -H103 uses STM3 F103RB.
If you are looking for a board with similar processor and Ethernet functionality take a look at
STM3 -E407 board. It uses STM3 H407ZG.
1.4 Document Organization
Each section in this document covers a separate topic, organized as follows:
–Chapter 1 is an overview of the board usage and features
–Chapter contains the board's layout
–Chapter 3 provides a guide for quickly setting up the board
–Chapter 4 describes the component that is the heart of the board: the STM3 F405
microcontroller
–Chapter 5 is an explanation of the control circuitry associated with the microcontroller to
reset. Also shows the clocks on the board
–Chapter 6 covers the connector pinout, peripherals and jumper description
–Chapter 7 shows the block diagram and the memory map
–Chapter 8 provides the schematics
–Chapter 9 contains the revision history, useful links and support information
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OLIMEX© 016 STM3 -H405 user's manual
CHAPTER 2: BOARD DESCR PT ON
In this chapter you will get acquainted with the main parts of the board. Note the names used on the
board differ from the names used to describe them. For the actual names check the STM3 -H405
board itself.
2.1 Layout (top view)
The picture below shows the top side of the board and highlights the most important parts.
Notice that all on-board jumpers are SMD type – in order to change the position of the jumpers you
would either need to cut between the pads of the jumper or solder the pads together.
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OLIMEX© 016 STM3 -H405 user's manual
2.2 Layout (bottom view)
The two most important parts at the bottom of the board are the two 6-pin headers EXT1 and
EXT . They allow easier access to some of the pins of the microcontroller. Refer to the pinout on
the next page for more detailed information on the signals available on EXT1 and EXT .
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2.3 EXT pinout (bottom view)
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OLIMEX© 016 STM3 -H405 user's manual
CHAPTER 3 SETT NG UP THE STM32-H405 BOARD
3. ntroduction to the chapter
This section helps you set up the STM3 -H405 development board for the first time.
Please consider first the electrostatic warning to avoid damaging the board, then discover the
hardware and software required to operate the board.
The procedure to power up the board is given, and a description of the default board behavior is
detailed.
3.1 Electrostatic warning
STM3 -H405 is shipped in a protective anti-static package. The board must not be exposed to high
electrostatic potentials. A grounding strap or similar protective device should be worn when
handling the board to avoid electrostatic discharge.
3.2 Requirements
In order to set up the STM3 -H405 optimally you would need a hardware debugger tool and
compatible software tools. More detailed information may be found in the sub-chapters below:
3.2.1 Hardware requirements:
- Standard ARM JTAG/SWD debugger/programmer – it can power the board and gives you the
ability to program/debug the board – to select the correct tool make sure that it is compatible with
the software tools which you are going to use during development. Also makes sure that the tool is
compatible with the STM3 F405 processor.
IMPORTANT: The board can be programmed using only a USB cable. However, it is a slow
process – this way of programming is not suitable for evaluation, research and development. Using
the USB DFU bootloader might be good idea only if you need to program the board once or twice.
Additional components can be acquired in order to increase the functionality of the board:
- USB cable with type A and type B connectors – in case you want to power the board from the
USB port of your personal conputer or, alternatively, if you want need to utilize the board's USB
interface
- Jumper wires – allow solderless access to the exposed pins; if you want to directly connect to the
extension headers use wires with a female connectors.
Some of the suggested items can be purchased by Olimex, for instance:
ARM-USB- INY-H – high-speed OpenOCD ARM JTAG debugger
ARM-USB-OCD-H – high-speed OpenOCD ARM JTAG debugger with buffer protection
ARM-J AG-COOCOX – high-speed CooCox IDE JTAG/SWD debugger
USB-A-B-CABLE – cable with USB type A and USB type B connectors at each end
JW-200x10-FM – ten jumper wires with female-male connectors
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OLIMEX© 016 STM3 -H405 user's manual
3.2.2 Software requirements:
In order to change the code on the board you would need an ARM C compiler and debugger
software, the possible software options are:
- free open-source software: OpenOCD (all Olimex OpenOCD JTAG debuggers are supported in
OpenOCD)
- free software: CooCox IDE (all Olimex JTAGs are supported in CooCox)
- commercial software: EW-ARM from IAR Systems AB; CrossWorks from Rowley (all Olimex
OpenOCD JTAG debuggers are supported in IAR and Rowley Crossworks; note that our debugging
tools doesn't work in Keil MDK-ARM).
Comparison table
Is it free or
commercial
Initial
struggle
and set-up
time
STM32-H405
example
pro ided by
Olimex
Is it
open-
source
Does it work
with Olimex
OpenOCD
debuggers
Quality of
customer
support
OpenOCD Free Highest No Yes Yes Bad
CooCox IDE Free High No No Yes Mediocre
Rowley
Crossworks
for ARM
Commercial (free
time-limited
e aluation
ersion)
Low No No Yes Good
Keil
MDK-ARM
Commercial (free
size-limited
e aluation
ersion)
Low No No No Good
IAR EW
for ARM
Commercial (free
size-limited
ersion and free
time-limited
e aluation
ersion)
Low Yes No Yes Good
It is a good idea to study the example that is provided by Olimex for your board. If you are not
willing to purchase the software just use the evaluation version initially.
Specifically, for STM3 -H405 Olimex provides only IAR EW for ARM example. It is a good idea
to download the latest time-limited evaluation version.
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3.3 Powering the board
The board can be powered in one of the following ways:
1) Using the JTAG or SWD debugger – the board gets powered via the 0-pin 0.1” step JTAG
connector; note that some tool might hold the board in RESET state – make sure to release the
microcontroller from RESET to be able to see the execution of your code
) Using USB cable – the board gets powered via the USB connector; the power is provided,
typically, by your computer's USB port
3) Using external power supply – in this case, the board gets powered via the EXT header –
provide +5V DC to pin # 6 of this header; then connect the power supply's GND to pin # 5 of
EXT .
3.4 Programming the board
The programming of the board is also fairly straight forward (unlike the software development for
the board):
3.4.1 Using JTAG debugger
This is the recommended method of changing the software of the board. This is fairly simple from
hardware point of view – just plug the male 0-pin JTAG connector of your hardware tool to the 0-
pin female JTAG connector of STM3 -H405.
Refer to the documentation of your debugger and also to the documentation of the software of
choice on instructions how to set the environment.
3.4.2 Using USB cable
The board can be programmed without a debugger tool. In this case you only need a personal
computer that is able to run Windows software and an USB cable.
STM3 -H405 has a built-in USB DFU bootloader that allows such programming.
Programming STM3 -H405 via the bootloader is a slow process that requires the re-configuration
of SMD jumper. It is not recommend for initial evaluation, research and development (use any
ARM JTAG debugger instead). Using the bootloader might be good idea only if you need to
program the board once or twice.
How to do it:
1. Change the position of one of the boot SMD jumpers – B0_H/B0_L (the bottom one). By default
it is set to position B0_L – you need to change it to B0_H. This requires soldering.
. After the adjustment is done you can connect to the DfuSe software released by STM. It available
for download from STM's official web-site. Search for “STSW-STM3 080”.
3. Install the software and run it.
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OLIMEX© 016 STM3 -H405 user's manual
4. Connect the board via the USB cable to the personal computer.
5. The board should now be recognized in the software. The bootloader application provided by
STM3 is a bit strange. It works only with dfu files. To upload other binary files (hex, bin, s19) you
would need to use additional converter tool (“DFU File Manager”; it converts hex, bin, s19 to dfu
and vice versa). I highly recommend you to read carefully the document about the usage of the
Dfuse called “Getting started with DfuSe USB device firmware upgrade”. Search for “UM041 ”.
6. Note that once you've uploaded the software you would need to change the jumpers back to the
original position – else the bootloader would start every time and the user program (typically stored
in the flash memory) would not execute.
3.5 Prebuilt software
Upon powering the board the STAT and PWR LEDs should turn on.
The board comes with the software which was downloaded and used during the testing of the board.
This software and its source code could not serve any purpose to the customer, who purchased the
board, since it requires additional custom hardware. That is why there is a meaningful example
available for download at the web-page of the board. Please download and extract the following
archive which contains the recommended initial demo:
https://www.olimex.com/Products/ARM/ST/STM3 -H405/resources/STM3 -H405_examples.zip
Note that the demo can opened and compiled out-of-the-box ONLY with IAR Embedded
Workbench for ARM. You can get a free code-size or time-limited evaluation version of IAR EW
for ARM from their official web-site (requires registration).
Refer to the “ReadMe.txt” file inside the archive for more information.
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OLIMEX© 016 STM3 -H405 user's manual
CHAPTER 4 THE STM32F405 M CROCONTROLLER
4. ntroduction to the chapter
Some of the details about the main processor in the design of STM3 -H405 (STM3 F405RG) are
mentioned in this chapter. The information is a modified version of the datasheet provided by its
manufacturers from ST.
It is highly recommended to refer to the original datasheet which might be downloaded from the
ST's official web-side.
4.1 The STM32F405RG features
STM3 -H405 board uses STM3 F405RG microcontroller designed and manufactured by
STMicroelectronics. It has the following features that distinguish it from the rest of the family:
Core: ARM 3 -bit Cortex™-M4 CPU with FPU, Adaptive real-time accelerator (ART
Accelerator™) allowing 0-wait state execution from Flash memory, frequency up to 168
MHz, memory protection unit, 10 DMIPS/1. 5 DMIPS/MHz (Dhrystone .1), and DSP
instructions
Memories
1 Mbyte of Flash memory
19 +4 Kbytes of SRAM including 64-Kbyte of CCM (core coupled memory) data RAM
Flexible static memory controller supporting Compact Flash, SRAM, PSRAM, NOR
and NAND memories
LCD parallel interface, 8080/6800 modes
Clock, reset and supply management
1.8 V to 3.6 V application supply and I/Os
POR, PDR, PVD and BOR
4-to- 6 MHz crystal oscillator
Internal 16 MHz factory-trimmed RC (1% accuracy)
3 kHz oscillator for RTC with calibration
Internal 3 kHz RC with calibration
Sleep, Stop and Standby modes
VBAT supply for RTC, 0×3 bit backup registers + optional 4 KB backup SRAM
3×1 -bit, .4 MSPS A/D converters: 4 channels and 7. MSPS in triple interleaved mode
×1 -bit D/A converters
General-purpose DMA: 16-stream DMA controller with FIFOs and burst support
Up to 17 timers: up to twelve 16-bit and two 3 -bit timers up to 168 MHz, each with up to 4
IC/OC/PWM or pulse counter and quadrature (incremental) encoder input
Debug mode
Serial wire debug (SWD) & JTAG interfaces
Cortex-M4 Embedded Trace Macrocell™
114 I/O ports with interrupt capability
Up to 15 communication interfaces
3 × I C interfaces (SMBus/PMBus)
4 USARTs/ UARTs (10.5 Mbit/s, ISO 7816 interface, LIN, IrDA, modem control)
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OLIMEX© 016 STM3 -H405 user's manual
3 SPIs (37.5 Mbits/s), with muxed full-duplex I S to achieve audio class accuracy via
internal audio PLL or external clock
 × CAN interfaces ( .0B Active)
SDIO interface
Advanced connectivity
USB .0 full-speed device/host/OTG controller with on-chip PHY
USB .0 high-speed/full-speed device/host/OTG controller with dedicated DMA, on-
chip full-speed PHY and ULPI
10/100 Ethernet MAC with dedicated DMA: supports IEEE 1588v hardware,
MII/RMII
8- to 14-bit parallel camera interface up to 54 Mbytes/s
True random number generator
CRC calculation unit
96-bit unique ID
RTC: subsecond accuracy, hardware calendar
For comprehensive information on the microcontroller visit the ST’s web page for a datasheet.
At the moment of writing the microcontroller datasheet can be found at the following link:
http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00037051.pdf
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OLIMEX© 016 STM3 -H405 user's manual
CHAPTER 5 CONTROL C RCU TY AND HARDWARE MODULES
5. ntroduction to the chapter
Here you can find information about reset circuit and quartz crystals locations, the power supply
circuit is discussed.
5.1 Reset
The reset circuit is connected to pin #7 (NRST) of the STM3 F405RG microcontroller. STM3 -
H405's reset circuit includes R8 (10 kΩ), C19 (100nF) and a RESET button.
The reset signal is also available on pin # 5 of the EXT1 header. It is also available at pin #15 of the
JTAG connector.
5.2 Clocks
There are two quartz crystals available on the board:
8 MHz quartz crystal Q1 is connected to pins 5 and 6 of the ARM microcontroller.
Quartz crystal Q is a 3 768Hz RTC (real-time clock) and it is connected to microcontroller's pins
3 and 4.
5.3 Power supply circuit
The power supply circuit of STM3 -H405 allows the board to be powered by three sources.
The most used interface for powering is the USB type B connector. It works at 5V DC.
The board can also be powered via the on-board JTAG connector. In that case the board receives
3.3V DC from the debugger tool.
Finally, the board can be powered from the EXT headers. The best location to power the board
would be pins # 6 (+5V DC) and # 6 (GND) from the EXT connector. Double check the pin
locations before providing the power.
The board consumes around 0. W (e.g. 0.04A at 5V) with both LEDs on.
By default, if you have successfully powered the board both LEDs would turn on. In case you you
have modified the software the green LED might not turn on since it is initialized by the code
loaded on-board. The red LED should always turn on upon powering. Note that it is possible to
have the PWR LED on even if there isn't enough power for proper operation of the board and all the
peripherals currently connected.
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OLIMEX© 016 STM3 -H405 user's manual
CHAPTER 6 CONNECTORS AND P NOUT
6. ntroduction to the chapter
In this chapter are presented the connectors that can be found on the board all together with their
pinout and notes about them. Jumpers functions are described. Notes and info on specific
peripherals are presented. Notes regarding the interfaces are given.
6.1 USB connector
The USB type B connector allows you to access the USB functionality of STM3 -H405. This
connector is can be used to power the board. The connector is sturdy and typically lasts much
longer during extensive use compared to the USB mini or USB micro connectors.
Note the DFU bootloader uses the USB port.
The signals follow the familiar and standard USB pattern:
USB Type B
PIN# SIGNAL NAME
1+5V_USB
2USBDM
3USBDP
4GND
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OLIMEX© 016 STM3 -H405 user's manual
6.2 JTAG/SWD debug connector
The board can be debugged from the 0-pin JTAG connector either by a debugger with compatible
connector. The on-board JTAG connector has 0.1” step of its pins. Below is the table with the
signals of the JTAG. This interface can be used with the Olimex's OpenOCD debuggers. It is also
compatible with most of the ARM debuggers available on the market.
JTAG/SWD debug connector
Pin # Signal
Name Pin # Signal Name
13.3V 23.3V
3TRST 4GND
5TDI 6GND
7TMS 8GND
9TCK 10 GND
11 GND 12 GND
13 TDO 14 GND
15 RST 16 GND
17 GND 18 GND
19 GND 20 GND
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6.3 EXT connectors
At the bottom of the board there are two extension rows of pins. These x 6-pin connectors
combine different processor ports and provide very nice GPIO option – you can interface the
signals exposed with your breadboarding wires; you can use them as headers; you can take signal
readings; etc.
The distance between two pins from the same row is 0.1''. The distance between the two EXT
connectors is exactly 1''.
Refer to sub-chapter .3 “EXT pinout (bottom view)” for visual representation of each pin of the
connectors.
6.3.1 EXT1 header
EXT1 HEADER
PIN # STM32H405 PIN PIN # STM32H405 PIN
1PA11 2PA8
3PA12 4PA9
53.3V (VDD) 6GND
7PA10 8PC10
9PC11 (DISC) 10 PC12 (LED)
11 PD2 12 PB5
13 PB 14 PA
15 PB7 16 PB8
17 PB9 18 PA5
19 PC0 20 PC1
21 PB0 22 PA7
23 VBAT 24 PC13
25 RST 26 PB1
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6.3.2 EXT2 header
EXT2 HEADER
PIN # STM32H405 PIN PIN # STM32H405 PIN
1VDDA 2PC2
3VSS (AGND) 4PA0
53.3V (VDD) 6GND
7PA2 8PA1
9PC3 10 PA3
11 PA4 12 PC4(USB_P)
13 PC5 14 PB10
15 PB11 16 PB13
17 PB12 18 PB14
19 PB15 20 PC
21 PC7 22 PC8
23 +5V_USB 24 PC9
25 GND_VSS 26 VIN
6.4 Jumper description
Please note that all of the jumpers on the board are SMD type. If you feel insecure in your
soldering/cutting technique it is better not to adjust the SMD jumpers.
6.4.1 BOOT memory select jumpers
B1_H/B1_L and B0_H/B0_L are SMD jumpers which define the initial boot default priority of the
microcontroller (aka which memory to boot from). By default they are set so that the board would
boot from the user Flash memory.
Notice that these two jumpers must be moved together – they are responsible for the boot mode if
bootloader is present. The board can search for bootloader on three places – either the user Flash
memory, the System memory, or the Embedded SRAM.
By default, B0_H/B0_L is set to position B0_L; the other jumper B1_H/B1_L is set to B1_L – in
this configuration the board will try to boot from user Flash memory.
To boot from the system memory you need to change the position of B0_H/B0_L jumper to position
B0_H. The boot loader is located in system memory (if you want to program the board via the USB
and DFUse software – use this mode).
Changing both high positions (B0_H/B0_L to B0_H; and B1_H/B1_L to B1_H) would attempt to
boot from the Embedded SRAM.
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