NXP Semiconductors LPC55S Series User manual

LPC55Sxx Safety Example
NXP Semiconductors Document identifier: IEC60730BLPC55SXXEUG
User's Guide Rev. 3, 07/2021

Contents
Chapter 1 IEC60730B Safety library example user's guide...................................3
Chapter 2 Hardware settings................................................................................. 4
Chapter 3 File structure......................................................................................... 8
Chapter 4 Example application............................................................................ 10
Chapter 5 Running example................................................................................ 14
Chapter 6 IEC60730B tests................................................................................. 24
Chapter 7 Revision history...................................................................................27
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Chapter 1
IEC60730B Safety library example user's guide
For easier development of the IEC60730B application, the library also provides the example code. This example is distributed
through the MCUXpresso SDK website. This example user's guide describes how to set the hardware correctly and how to use
the example code with the IEC60730B Safety library.
The library user's guide is the main documentation for IEC60730B. It is also part of this package and you can download it at
www.nxp.com/IEC60730.
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Chapter 2
Hardware settings
This chapter describes how to set up the hardware of the evaulation board. The MCU peripherals' setup is described later on.
The IEC60730B library example for the LPC55Sxx family supports the following development boards:
• LPCxpresso55S69
• LPCxpresso55S36
• LPCxpresso55S28
To run the IEC60730B example application, it is neccessary to make some hardware settings. For the default configuration of your
development board, see the corresponding board's user manual at www.nxp.com.
2.1 LPCXpresso55S69
Debugger:
To use the on-board debugger and power the board via USB, make sure that jumper J3 is set to "Loc". Then connect the USB to
connector P6.
The default debugger in the example project is set to CMSIS-DAP.
If downloading to the device does not work, press and hold the S1 button during the download.
NOTE
FreeMASTER
FreeMASTER communication is used via an onboard debugger with a speed of 9600 bd.
See the Hardware User’s Guide for more options.
The ADC module on LPCXpresso55S69 does not allow to connect the Bandgap internally to the ADC input. It is necessary to
connect these signals (for the Analog I/O test) as follows:
• VrefH 3.3 V is connected internally.
• VrefL - GND is connected internally.
• Bandgap - connect a custom reference (for example 1.65 V) to PIO0_23 (P19-4). The expected value of the custom bandgap
can be set in the
safety_config.h file (#define ADC_EXTERNAL_PIN_LEVEL 1.65).
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Figure 1. Hardware connection of LPCXpresso55S69
The test voltage of 1.65 V is provided by a resistor voltage divider from the VCC (3.3 V).
2.2 LPCXpresso55S36
Debugger:
To use the on-board debugger and power the board via USB J1, make sure that jumper J27 is "Open".
The default debugger in the example project is set to CMSIS-DAP.
FreeMASTER
FreeMASTER communication is used via an onboard debugger with a speed of 9600 bd.
The ADC module on LPCXpresso55S36 does not allow to connect the Bandgap internally to the ADC input. It is necessary to
connect these signals (for the Analog I/O test) as follows:
• VrefH 3.3 V is connected externally to PIO0_31 (J9-5)
• VrefL - GND is connected externally to PIO0_16 (J9-3)
• Bandgap - connect a custom reference (for example 1.65 V) to PIO0_15 (P9-1). The expected value of the custom bandgap
can be set in the
safety_config.h file (#define ADC_EXTERNAL_PIN_LEVEL 1.65).
LPCXpresso55S36
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Figure 2. Hardware connection of LPCXpresso55S36
The test voltage of 1.65 V is provided by a resistor voltage divider from the VCC (3.3 V).
2.3 LPCXpresso55S28
Debugger:
To use the on-board debugger and power the board via USB, make sure that jumper J3 is set to "Loc". Then connect the USB to
connector P6.
The default debugger in the example project is set to CMSIS-DAP.
If downloading to the device does not work, press and hold the S1 button during the download.
NOTE
FreeMASTER
FreeMASTER communication is used via an onboard debugger with a speed of 9600 bd.
See the LPCXpresso55S69/55S28 Development Boards User Manual (document UM11158) for more details.
LPCXpresso55S28
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The ADC module on LPCXpresso55S28 does not allow to connect the Bandgap internally to the ADC input. Thus, it is necessary
to connect these signals (for the Analog I/O test) as follows:
• VrefH 3.3 V is connected internally.
• VrefL - GND is connected internally.
• Bandgap - connect a custom reference (for example 1.65 V) to PIO0_23 (P19-4). The expected value of the custom bandgap
can be set in the safety_config.h file (#define ADC_EXTERNAL_PIN_LEVEL 1.65).
Figure 3. Hardware connection of LPCXpresso55S28
The test voltage of 1.65 V is provided by a resistor voltage divider from the VCC (3.3 V).
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Chapter 3
File structure
Safety is only a small part of the whole SDK package for your device. The IEC60730 library and examples are located in the
middleware and in the board folders. The IEC60730 library is independent of the SDK and can be used stand-alone.
3.1 Library source files location
The library source files are in the middleware/safety_iec60730b/safety/v4_2 folder in the SDK package.
The folder has the following structure:
Figure 4. Folder structure
Where:
• The
common_test folder contains the source files for the peripheral test – this is a common cross core. These tests are
compiled to library libIEC60730B_<core>_COM_<compiler>_<version>.a .
• The compiler folder contains compiler support files.
• The
core_test folder contains the source files for the core-dependent test. These tests are compiled to library
libIEC60730B_<core>_<compiler>_<version>.a .
• iec60730b.h is the main library header file.
•
iec60730b_types.h is the header file with the necessary defines for the library.
The folder also contains binary *.lib files, which are compiled for the IAR, Keil, and MCUXpresso IDEs (see the release notes
for details).
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3.2 Example of library handling code
The library-handling code and the example aplication are separate from the library file. The example source files and other SDK
examples are at this path:
boards/<your board>/demo_apps/safety_iec60730b/
The safety example code is shown in Figure 5.
Figure 5. Example of project structure in example folder
This folder contains the example source file and three folders for the IDE project file:
•
iar
• mcux
• mdk
The following files are generated by the MCUXpresso configuration tool:
• clock_config.h
• clock_config.c
• pin_mux.c
• pin_mux.h
Other files are used only for safety examples and their contents are described in the next chapter.
Example of library handling code
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Chapter 4
Example application
The structure of the example is common in all supported IDEs (IAR, Keil, MCUXpresso).
Figure 6. IAR example application structure
The project contains the CMSIS, SDK, library, and safety example-related folders.
The safety-related folders are the following:
•
Board – this folder contains the files related to the board used ( clock_config.h , pin_config.h , board.h , and so on).
• CPU – this folder contains the startup code and vectors table.
•
IEC60730_Class_B – files for the IEC60730B Safety library.
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