Bosch XDK110 General Information Manual page 44

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4. Interfaces
4.1 Extension Interface
The connection interface allows access to additional functionality of the MCU, such as radios or
sensors. This way, developers can use the hardware and software of XDK for testing out new
components with minimal application effort. All MCU pins are GPIOs and can be configured freely
within the limitations of the MCU. Suggestions for usage are given to highlight dedicated functions
available on these pins in the Table 7. For further information on the MCU pin functionality, please
refer to the MCU data
Warning: Damage due to incorrect Voltage
The equipment can be damaged by using an inadequate power source. This can cause serious
injury and damage to materials.
Do not connect the power supply pins to an external power source!
4.2 Connecting External Components to the XDK
4.2.1 Connecting the "XDK Gateway" Extension Board
Connect the 26-pin cable (included in delivery) to the "XDK Gateway" board and to the 26-pin
connector of the XDK 110. The "XDK Gateway" offers a simple way to implement additional
functions. It is optimized for the use with breadboards.
4.2.2 Connecting Your Own Components to the XDK Gateway Board
The XDK Gateway board I/O pins are labeled with the respective MCU pin designator. Some of the
pins can be configured to cater several functions. However, due to shared resources with internal
components, restrictions apply to the possible configurations of the extension bus.
Warning: Function Limitations
Before you start connecting external components to the XDK, please note the following limitations:
GPIO pins voltage is 2.5V. If you connect external components that work on a different voltage
level, a level shifter has to be used to ensure communication with the MCU. Failing to do so can
lead to permanent damage of the XDK!
The microcontroller supports four GPIO pin drive strength settings: 0.5, 2, 6 and 20 mA. The
default drive strength is set to 6 mA and an alternative level can be defined for each port. Pins of a
given port can select the configured alternative drive strength individually. While each pin can
receive or provide maximum 20 mA current, there is a limit on the maximum combined current
sourced or sank by all GPIOs. As the XDK board itself has many useful peripherals connected to
the MCU that may require specific alternative drive strength settings if enabled, it is recommended
to use the default 6 mA drive strength for all IO pins of the extension board connector and to
limit the total amount of current sourced or sank through the extension board bus to 50 mA.
Exceeding these limits might permanently damage the microcontroller!
XDK110
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copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.
Note: Specifications within this document are subject to change without notice.
General Information Guide XDK110
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