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Introduction GUI Guider is a user-friendly graphical user interface development tool from NXP that enables the rapid development of high quality displays with the open-source LVGL graphics library. GUI Guider's drag-and-drop editor makes it easy to utilize the many features of LVGL such as widgets, animations and styles to create a GUI with minimal or no coding at all. In recent years, Smart Home has emerged rapidly and has a strong momentum of development. Smart Homes connect various household appliances and provide services such as lighting control, telephone remote control, burglar alarm and environmental monitoring. Smart Home applications are more and more widely used, but it is difficult for many developers to start. Using NXP GUI Guider can improve the development speed, reduce development difficulty, shorten development cycle. This article mainly introduces the use of GUI Guider to realize some functions of Smart Home, and shares some common methods in the use of GUI Guider, including creating a new project, adding controls, adding events, interface design and layout, and controlling the lighting of hardware lights. Development environment 2.1 Hardware environment Evaluation of LPC54628 -LPCXpresso54628, also applies to LPCxpresso54618, LPCxpresso54608. 2.2 Software Environment This Smart Home demo uses GUI Guider version 1.5.1 to set up the software environment. GUI Guider version 1.5.1 supports LVGL versions 7.10.1 and 8.0.2. This introduction is based on version 8.0.2 LVGL. Download link: https://www.nxp.com/design/software/development-software/gui-guider:GUI-GUIDER Create a new project 3.1 Double-click the GUI Guider icon to start the GUI Guider.   3.2 Click Create a new project (" Create a New Project ") button to start the project creation process.   3.3 select LVGL version v8.3.2 and click Next button.   3.4 Select LPC54628 as the target board template and click Next button.   3.5 Select empty application template EmptyUI and click Next.   3.6 Perform the project Settings, and set the project name, project location, and screen type (select RK043FN66H or RK043FN02H according to your screen type). Click Create to create the project.   3.7 After the project is created, the interface is as follows.   Page Design and Layout This section describes how to adjust the background color, layout, add various controls (Such as images, image buttons, text, and containers , etc), and set properties. 4.1 Create the image folder, and put the image resources needed in the project under the established image folder.   4.2 Adjust the background color of the interface ① Click the Background color icon to open the background color Settings. ② You can set the background Gradient or monochrome by using Gradient. ③ Then select the background color.   4.3 Add images ① Open Widgets control options. ② Click to add the Image control. ③ Then click the image shape button in the Attribute box of the property Settings, and “Select Images” will pop up. In “Select Images”, select the image you want to add, click OK to add the image, and adjust the image size and position.   In the same way, you can add the "small house" image. In the Widgets box, you can view the added image and set the image name. In the Screen box, you can view the current interface and set the interface name.   4.4 Add text ① Open the control options, select and click the Label control. ② In Property Settings Text, set the text content to SMART HOME. ③ Then click the Background background setting area to set the Label control background. ④ Set the color depth of the Label control to 0, without background color. ⑤ Set the Font color, size and style in the font.   4.5 Add a container Containers are essentially basic objects with layout and automatic resizing capabilities. Open the control option, click Container to add the Container control, and drag the control size. Set the background color in the property Settings. ③ Then set the Border and rounded corner of container in "Border".   Name the added Container control cont_TodayInfo. Add other controls to the Container control. You can view other controls (including picture, text, and line controls) added to the cont_TodayInfo container in the Widgets.   4.6 Add an Image button Image button are very similar to simple "button" objects. The only difference is that it displays image in each state defined by the user. ① Open component options, select and click the Imgbtn control. ② Add the Released and Pressed images.   In the same way, add other Imgbtn controls and Label controls.   Switch the interface This section describes how to create sub-interfaces and switch between the main interface and sub-interface. 5.1 Add a second new interface Click “+” to add a new screen, rename the new screen src_Light, add Image, imgbtn controls, and change the background color.   5.2 Add interface switching trigger conditions ① Select the imgbtn_Light button on the first screen. ② Select the Events Settings. ③ Click “+” to add an event, and then set the event. ④  In event Settings, trigger conditions need to be selected, here Clicked trigger conditions are selected. Target Select the second new interface src_Llight that you want to load, and then select the Delete current interface option. When the program is running, when the imgbtn_Light button is clicked, it will switch to the second src_Light interface.   Updating Media   5.3 Add a trigger condition for returning to the interface ① Select the imgbtn_Home control. ② In the event Settings, select Clicked trigger conditions, Target select src_Welcome for the interface to be loaded, and select Delete the current interface option. When the program is running, when the imgbtn_Light button is clicked, it returns to the first main screen of src_Welcome.   5.4 Design the second interface Add controls in the second interface, including Switch control, Slider control, Dropdown control, Image control, Imgbtn control, Label control. Switch control: This switch can be used to turn the light on/off and it looks like a small slider. Slider control: The slider object looks like a bar supplemented with knobs. You can drag the knob to set the value. The slider can be vertical or horizontal. Dropdown control: A drop-down list allows the user to select a value from a list. By default, the drop-down list is turned off and displays a single value or predefined text. The Image control, Imgbtn control, and Label control are described in the previous section.   Control hardware light design Smart home usually has the control of the light, through the control interface to control the hardware light on and off, the steps are as follows: 6.1 GUI Guider generates code project ① Generate the code by clicking the Generate code button. ② Click the Folder icon to open the project folder   6.2 Starting the MDK Project After the generated code is completed, open the project folder and open the MDK project in the specified directory (support MCUXpressoIDE, MDK, IAR).   6.3 First, the drive to control the light switch is added to the project Add a GPIO initializer in lvgl_guider.c.   6.4 then, add a custom Led control function under Custom.c This routine adds Led1_Control, Led2_Control, and Led3_Control lamp control functions.   6.5 Add custom event program to GUI Guider ① Select the first Switch control and add the event. ② In the event, select Trigger to trigger the event condition that the Switch control is on and off, and the Target option is set to Null.  In Action, select C to add custom events and click to open Edit Code.  Add a custom event function to Edit Code (open Led3, close Led2, Led1), and add the header file of the file where the custom event function is located.   6.6 View custom events in the MDK project After setting the custom event, the set Led custom trigger event can be found on events_init.c after the GUI Guider regenerates the code again.   Program download and demo After the project is completed, there are two ways to download the program to the development board: Open the project with IDE (MCUXpresso IDE, KEIL or IAR), compile and download the program to the development board. Selecting MCUXpresso, Keil, or IAR from Target in the GUI Guider automatically compiles the program to download to the board. The following diagram shows how Guider automatically compiles the download program to the development board in GUI.   Attached video shows the effect.   8.In SUMMARY This artical mainly shares the Smart Home interface design based on GUI Guider. GUI Guider, as a tool for GUI design, is powerful and easy to use. This article only uses a few functions of GUI Guider, we can further learn to explore GUI Guider, the related project has been placed in the attachment. The GUI Guider application guide can be found on the NXP official website, and the following are some ways to find information when learning to use GUI Guider. View the User Guide and click Help->User Guide   control Settings and usage instructions, you can click the following small icon to view    
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Contents     Introduction to OPAMP. ........................................1     Usage of LPC5536-OPAMP. ................................2 2.1 Follower OPAMP. .................................................2 2.2 Non-inverting OPAMP. .........................................3 2.3 Differential OPAMP. ..............................................3     Test Preparation of LPC5536-EVK. ......................4     Test Result ............................................................5 4.1      Follower Test ....................................................6 4.2      Non-inverting Test ............................................7 4.2.1 Error Analysis. ...................................................7 4.2.2 Gain Error and Output Offset Error ...................8 4.2.3 OPAMP Output Error .........................................9 4.4 Differential Test ...................................................10     Conclusion. .........................................................11   The Article shows the OPAMP performance test that the precision of LPC5536-OPAMP matches the description in the product data sheet. The gain error is less than 5%, and the input offset voltage is less than 5mV, which can meet the presicion need to a certain extent. It is worth mentioning that the output error of LPC5536-OPAMP is very small at low magnification. For example, the full-range error is just single-digit mV at the magnifications of 2X and 5X in non-inverting mode. For scenarios requiring higher precision, users can connect the external high-precision resistors to achieve higher output precision.  The article includes detailed test steps and EVK board settings. For detail, see attached article.  
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Because the LPC55S69 has PowerQuad, in SDK example code, the FFT/FIR/IIR and the other DSP function are implemented by the Powerquad module instead of the Cortex-CM33 core.  This is the Powerquad example to implement the DSP function:'   But if customers want to use CMSIS-DSP to implement the DSP function based on Cortex-CM33 instead of Powerquad module, customers can not import SDK example, he has to create a new project, this is the procedures: 1)Create a new project by clicking New->Create a new C/C++ Project   2)select the processor like LPC55S69 3)In the following menu,click CMSIS Driver, and check the CMSIS_DSP_Library and CMSIS_DSP_Library_Source You have to click the Driver which can select your peripherals driver you will use.    3)as the following screenshot, after completion, you can see the CMSIS-DSP source code and library have included in the project    
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After LPC54XXX enter ISP mode, there are two methods to upgrade the application through UART/I2C/SPI/USB. One method is to change the ISP pin state when power on, and the other method is to reinvoke ISP Boot ROM in source code during code running. The first method does not require user to write any code, and the operation is simple, but the disadvantage is that it is not flexible and is not suitable for on-site operation; The second method is more flexible and is widely used in Secondary Bootloader applications developed by yourself, but it requires users to write their own code. In actual development, because the USB port of personal computer is easy to use, the method of using the USB port for application upgrade is becoming more and more popular. Unfortunately, we currently do not have instructions for upgrading the application by the USB port in ISP mode. So we write this article to share the method here.   There are two methods to enter ISP mode: Method 1: Enter ISP mode to upgrade the application during power on On the hardware side, configure the ISP0~2 pins before power-on or reset, and the MCU enters ISP mode to upgrade the application. The pin configuration method is as follows: Figure 1.   Method 2: Activate Reinvoke ISP in source code to upgrade the application In ISP mode, the application is upgraded through UART/I2C/SPI/USB. This article focuses on the USB method. Here for USB, Both USB0 (Full Speed) and USB1 (High Speed) of LPC54XXX can be used for application upgrade. There are two USB upgrade modes: DFU (Device Firmware Updata) and MSC (Mass Storage Device Class), as follows: Figure 2.   Select the application upgrade mode by modifying byte 0 and byte 1 of the ISP parameter array. The key code is as follows Figure 3.   There are 3 key point we need to pay attention in Figure 3: -When isp_mode[0] is configured as 0xAA, it is DFU mode, otherwise it is MSC mode (for example, isp_mode[0] is configured as 0xFF). -When isp_mode[1] is configured as 8, USB FS is used, and when it is configured as 9, USB HS is used. -Enter the ISP mode through the Chip_IAP_ReinvokeISP function. 2.1 Use DFU for application upgrade Tool preperation: To work with DFU, dfu-util tool is needed to use DFU to upgrade the application, you can download the DFU tool on the DFU official website. The link is as follows: http://dfu-util.sourceforge.net/ NXP also includes the dfu-util tool in LPCScrypt. If you have downloaded LPCScrypt, you can use it directly in the bin directory.   DFU update application Steps: Take LPC54628 as an example, ISP is configured as DUF mode, and USB1 is used to upgrade the application. Modify the relevant code in Figure 3, as follows: isp_mode[0] = 0xAA; isp_mode[1] = SL_USBHS; Build and download the application to the MCU, power on again, and connect USB1 to the computer. Here Enter the dfu-util tool directory and copy the .bin file to the current directory. Use the command: ./dfu-util -l   Find the DFU devices. Use the command: ./dfu-util -D .\lpcxpresso54628_gpio_led_output.bin -a 0 Download the lpcxpresso54628_gpio_led_output.bin file to the device with alt number 0. Alt0 is "FLASH", alt1 is "RAM", and the specific operations are as follows:   Figure 4.   After downloading the application successfully, reset the MCU and observe the blinking phenomenon of the LED on the development board.   2.2 Use MSC for application upgrade Take LPC54628 as an example, ISP is configured as MSC mode, and USB1 is used to upgrade the application. Modify the relevant code in Figure 3, as follows: isp_mode[0] = 0xFF; isp_mode[1] = SL_USBHS; Build and download the application to the MCU, power on again, and connect USB1 to the computer. You will found another disk in my computer, as follows: Figure 5.   Then do the following to update firmware: -Remove the original firmware.bin in the CRP DISABLD disk. -Rename the application (for example, lpcxpresso54628_gpio_led_output.bin) to firmware.bin. -Copy the application firmware.bin to the CRP DISABLD disk. -Reset the MCU, if the LED is observed blinking, it proves that the application has been successfully upgraded. Note: The application must be renamed, and the rename cannot be performed in the CRP DISABLD disk.   Demo project:lpcxpresso54628_flashiap.zip Application upgrade file:lpcxpresso54628_gpio_led_output.bin (generated by SDK demo code)
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  需求: 客户需要对Image文件做出完整性检测,利用IDE固有功能添加这类信息简便且可靠,以往有类似的link提到了这些配置,对于LPC55系列,需要做一些更新。 CRC Checksum Generation with MCUXpresso IDE - NXP Community Solution 基于MCUX环境 下载 SRecord http://srecord.sourceforge.net/ srec_cat.exe是下载后我们主要使用的工具,通过为其添加一个系统变量名,将SRecord目录加入系统路径     重启MCUX IDE之后可以在工程配置中看到该变量:       创建一个脚本文件crc_add.txt,放在debug目录下,用于填充app后的flash空余位置为0xFF, 并后续生成CRC32值并放置0x00037FFC位置。最终生成的srec文件为包含所有内容的image。           # srec_cat command file to add the CRC and produce application file to be flashed # Usage: srec_cat @filename #first: create CRC checksum lpcxpresso55s06_hello_world_image_length_MCUX.srec # input file #-fill 0xFF 0x00000000 0x00038000 # fill blank code area with 0xff from 0x00000000 to 0x00038000 (0x00038000是把LPC55S06的末尾地址稍往前提,实际因为0x0003D7FF) -fill 0xFF 0x00000000 0x00037FFC #填充0-0x37FFC区间的未用地址为0xff -crop 0x00000000 0x00037FFC # just keep code area for CRC calculation below , 保留这段区间的内容,排除除此范围内的其他数据 #-CRC16_Big_Endian 0x00037FFE -CCITT # calculate big endian CCITT CRC16 at given address., 为以上空间数据计算CRC16,并放置在0x00037FFE地址,2字节 -CRC32_Little_Endian 0x00037FFC -CCITT #CRC32 -crop 0x00037FFC 0x00038000 # keep the CRC itself #second: add application file lpcxpresso55s06_hello_world_image_length_MCUX.srec # input file -fill 0xFF 0x00000000 0x00037FFC # fill code area with 0xff -crop 0x00000000 0x00037FFC #-crop 0x10000000 0x10000170 0x10000172 0x10010000 #keep all except CRC #finally, produce the output file -Output # produce output lpcxpresso55s06_hello_world_image_length_MCUX_crc.srec      创建一个crc_file_convert.txt文件,也放在debug目录下,用于将上一步生成的最终image的srec文件转换为bin文件,用于生成或者比对 # srec_cat command file to add the CRC and produce application file to be flashed # Usage: srec_cat @filename #third: create bin file lpcxpresso55s06_hello_world_image_length_MCUX_crc.srec -o lpcxpresso55s06_hello_world_image_length_MCUX_crc.bin -binary 在IDE的Post build栏目添加如下命令:     arm-none-eabi-size "${BuildArtifactFileName}"   默认自带的统计image size功能 arm-none-eabi-objcopy -v -O binary "${BuildArtifactFileName}" "${BuildArtifactFileBaseName}.bin"    将image转成bin文件,用于后续使用和比对 arm-none-eabi-objcopy -v -O srec "${BuildArtifactFileName}" "${BuildArtifactFileBaseName}.srec" & srec_cat.exe @CRC_add.txt 填充image,计算CRC32,整合成新的srec image srec_cat.exe @CRC_file_convert.txt  将上一步得到的srec image转化为bin文件,用于后续使用和比对   《hello_world_image_length_MCUX》例程会自行统计应用程序的CRC32值,并于IDE产生的CRC32值做比对   这里需要注意的是,由于MCUX IDE是借助于外部工具来填充flash和计算CRC32,所以默认IDE调试和下载选择afx文件并不包含这些信息。当校验程序开始运行,会发生: 读写未写入的flash,对于LPC55系列会发生hardfault CRC32值并不存在 所以测试这个程序需要单独下载包含所有的srec文件或者bin文件,而不是默认的afx文件。      
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The power measurement board includes eight measurement channels which support for eight programmable gain amplifiers(LTC6915) and two ADC converters(AD7175). The measurement board measures the voltage drop across sampling resistor, and send to the ADC after the voltage drop is processed by amplifier and make it available via SPI. Microcontroller LPC55S69 collects the data from the measurement circuit and send it to the host computer via USB VCOM port. The MCU can control the gain value of programmable gain amplifiers by SPI when different power circuit are measured. The host computer connects to the power measurement board through the USB virtual serial port, the MCU initializes and configures the measurement unit by SPI, and starts to measure the inside current and monitor the voltage. MCU adjust the gain parameter and then transmit current and voltage data to MCU by SPI, then MCU transmits the data to the host computer for processing and display through the virtual serial port. The voltage drop of the measured circuit to be measured is firstly amplified by the programmable amplifier LTC6915, and MCU monitor the state which whether the data is abnormal at the same time. R0 is the sampling resistor, LTC6915 is a selectable programmable amplifier, the gain can be set to 14 kinds, PGA gain parameter is adjusted when the current changes. ADC7175 is the 24-bit high-precision ADC, which is more advantageous in the application of small current measurement. When the MCU switches the low power mode to the normal mode, and the LTC6915 will reduce the gain value by SPI. The power measurement board provides easy connection method by two-wires cable. For example, the MIMXRT1180EVK and MIMXRT1020EVK are connected with power measurement board. The USB virtual COM is used for data transfer, and display by PMT(power management tool) or other PC GUI, the measurement power data include current, voltage and power. There are more detailed descriptions in the attachment.
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1.     Problem description When we debug a new designed LPC55 custom board through SWD, if IDE throws out error messages such as connection failure or no available device being found, normally we must check below two points: Whether the debug circuit design is correct.(https://community.nxp.com/t5/LPCXpresso-IDE-FAQs/Design-Considerations-for-Debug/m-p/469565#M44) Whether LPC55 power supply system is correct. Regarding to the second point of power supply system, we received many feedback from customers that even they read UM for times they still can’t well-understand LPC55xx DCDC power supply system. Therefore we prepare this article to analyze LPC55xx power supply circuit and introduce detection method. 2.     Problem Analysis The difference of power supply circuit between LPC55xx series and other LPCs is that LPC55xx uses DCDC circuit inside to provide core voltage. It lowers the input 1.8V-3.6V voltage to around 1.1V to supply LPC55xx internal system. The DCDC converter is efficient and reduces the internal power consumption. The disadvantage is that it generates a certain ripple. LPC55xx power supply circuit is as follows: In order to analyze, We divide LPC55xx power supply circuit into 4 regions and will introduce them one by one according to the different functions.   1)  Input voltage: In this part, VBAT_PMU provides input voltage to RTC and internal analog components. VBAT_DCDC provides input voltage to internal DCDC circuit. 2)  A set of filter capacitors: To filter out the burrs and glitch at the voltage input. 3)  DCDC circuit: Work with LPC55xx internal DCDC circuit together to generate 1.1V output voltage. 4)  VDD_PMU: Provides the 1.1V output voltage of the DCDC circuit to the LPC55xx core. Note: The design of region 3 is to work with the internal DCDC converter. The inductance L1 of 4μ7H and the capacitance C1 of 22μF are calculated by LPC55xx internal circuit. When designing, we must strictly follow the parameters recommended in the manual, otherwise DCDC circuit can’t work normally. 3.     DCDC Circuit Detection LPC55xx power supply system current direction is shown in the diagram below. See arrow in red. In order to ensure the normal operation of the DCDC circuit, the following two detection points are recommended. 1)  Detection point 1: External 1.8 to 3.6V voltage input, normally it’s 3.3V. 2)  Detection point 2: Output of the DCDC converter. If the DCDC works normally, we can get 1.1V voltage output here. The output voltage supplies power to the core components such as the central processing unit through the VDD_PMU. If DCDC convert input is correct but output wrong, we suggest checking inductor L1 and the capacitor C1 and related solder issue. If the voltage of two detection points are correct, the power supply circuit problem can be ruled out. 4.     summary: For custom designed LPC55xx board, if SWD design is correct and power supply system works well, IDE can connect, download and debug target without issue.  
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  [LPC546xx] Understanding ECRP   Code protection is usually considered at the last step during developing stage. The purpose is to protect our code being hacked when the product is released to market. For example, using ECRP to disable SWD debug interface, disable ISP, disable mass erase, etc. 1.    ECRP vs Legacy CRP   ECRP (Enhanced Code Read Protection) is versus legacy CRP on early LPC devices. We can consider ECRP as an advanced version of CRP. Comparing with CRP, ECRP adds new protection features: − Block ISP via Pins − Block ISP using IAP − Block SWD − Mass Erase enable/disable − Sector protection This table lists the difference of ECRP vs. CRP from Anti-Tampering and Flexible view. 2.    Understand and implement ECRP ECRP allows user to tenable below features: − Protect FLASH from ISP Erase/Write − Protect FLASH from IAP Erase/Write − Enable/Disable ISP Entry from bootloader − Enable/Disable ISP Entry from IAP call − Enable/Disable SWD Enable/Disable It looks easy but it is important to know that ECRP feature is controlled by both FLASH and OTP configuration! The most restrictive combination in both setting is needed 2.1          Where is FLASH ECRP: ECRP is at 0x20 of vector table, it’s uint32_t type. We write to this address to set FLASH ECRP protection. The valid bits of FLASH_ECRP is 0-17bit, and the default value is 0xFFFF_FFFF. For detail, please see UM.   2.2          Where is OTP ECRP OPT is a non-volatile and write-once register. OTP is not FLASH and it can be ONLY written by IAP function. OPT ECRP configuration is at OPT bank 3. The default OTP ECRP value is 0.   2.3          FLASH ECRP + OTP ECRP Decides the Protection. See this table to show the combination. Here OTP ECRP is always set with higher priority than FLASH ECRP! Here is typical ECRP settings 2.4        Be Attention! The part is permanently disabled when On-chip Image(s) are ruined SWD access prohibited ISP entries prohibited Please be attention when testing ECRP feature, mis-operation may make the chip brick!
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Recently I found some customers have a bit of problem when porting project from one MCU to another, so this article using simple steps demonstrates how to change MCU with MCUXpresso. There is also a video demonstrated the detail steps in attachment. Pay attention, as MCUXpresso User Guide says: All projects are associated with a particular MCU at creation time. The target MCU determines the project memory layout, startup code, LinkServer flash driver, libraries, supporting sources,launch configuration options etc. etc. so changing a project’s associated MCU should not be undertaken unless you have a total grasp of the consequence of this change. Therefore rather than changing a project’s associated MCU, it is strongly recommended that instead a new project is generated for the desired MCU and this new project is edited as required. However, on occasion it may be expedient to reset a project’s MCU (and associated SDK) and this can be achieved as follows. For example, changing lpc55s69 to lpc55s06, we need install SDKs for lpc55s69 and lpc55s06 before all the below steps. 1 - Change MCU & Package 1.1 – Change MCU Right click “MCU” under Project tree, choose “Edit MCU” Uncheck ”Preserve memory configuration”(it is checked by default)->choose LPC55S06->there is a warning, choose Yes. We can see the Memory details changed to lpc55s06, then click ”Apply and close”. 1.2 – Change Package 2 - Change Compiler Definitions In Properties view->Settings->MCU Compiler ->Preprocessor, change the definition for CPU from LPC55S69JBD100 to LPC55S06JBD64 as below: 3 – Change/add SDK driver for LPC55s06 Selected project, then click ”Manage SDK components”, choose the drivers our application used, for example, clock, power, usart. Click “OK”, then click “Yes” to update. Delete LPC55S69 device related files: Add “system_LPC55S06.c” and “system_LPC55S06.h” files: 4 - Change startup file. Delete LPC55s69 startup files, add “startup_lpc55s06.c”, we can find the startup file in any SDK demo. 5 - Change board related files. Refer to our own new board, change files under “board” folder, for example pins, uart number, here directly copy from SDK demo for LPCxpresso55s06 board. 6 - Test the project  function with new board Build project until no compile error, download and run it, result as below.        
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LPC: Regarding to Internal Clock Calibration In MCU development, using the internal crystal oscillator as a clock source instead of the external crystal oscillator can save costs. But the clock frequency generated by the internal crystal oscillator is affected by temperature and MCU frequency more than external crystal oscillator. Many customers have questions about the internal clock accuracy, whether the internal clock can be used for USB transmission, and how to calibrate the internal clock. This article mainly explains this. 1. Calibrate internal clock by FREQTRIM Normally, we can only calibrate the internal clock by adjusting the FREQTRIM value. The internal clock frequency is affected by temperature, MCU frequency and other factors. The FRO control register can calibrate the internal clock, as follows:   The FREQTRIM register value ranges from 0 to 255, and each adjustment step is about 0.1% of the internal clock frequency. There is no precise formula to express the relationship between the FREQTRIM value and the FRO frequency. The ideal FREQTRIM value can only be determined by adjusting FREQTRIM in code and observing FRO output waveform with oscilloscope. Test and observation: The following is the test result. It shows how FRO frequency varies with FREQTRIM increasing from 0-255. Test result of first development board:     Test result of second development board:   The following two points can be seen from test results: - There is no linear relationship between the FRO clock frequency and the FREQTRIM register value, and there is no precise formula to express the relationship between them; - Even for chips of the same part number, the internal clock frequency changes are slightly different, with the FREQTRIM register value changing, but the trend is same. Therefore, there is no precise formula to guide internal clock frequency calibration. You can only adjust the FREQTRIM register value repeatedly, just like adjusting the focus of a projector. Use an oscilloscope to check the frequency of the internal clock pin to find the most suitable FREQTRIM register value. There is same solution for FRO clock frequency calibration about other LPC chips.   2. LPC51U68: Software calibration USB transmission when using internal clock source The Full Speed USB module of LPC51U68 has a unique FRO automatic calibration function, which automatically adjusts the FREQTRIM value to achieve FRO calibration by measuring the USB SOF bit. Once FRO is calibrated, the corresponding system clock and peripheral clock are calibrated. This solution is only applicable to LPC51U68, please refer to the user manual for other chips. The following is the FRO clock accuracy described in LPC51U68 User Manual, which is ±1%:   For Full Speed USB, the USB data transmission accuracy requirement is ±0.25%, and the FRO clock accuracy is not satisfied. NXP provides a software solution to calibrate FRO by measuring the first packet of frame (SOF), which can meet the transmission accuracy in Full Speed mode.   The solution download link is as follows: https://www.nxp.com/docs/en/application-note/TN00035.zip  
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LPC55xx系列的MCUXpresso SDK使用FLASH API来实现FLASH驱动。 一些用户在执行如下FLASH写操作时可能会遇到如下的问题: status = FLASH_Program(&flashInstance, destAdrss, (uint8_t *)s_bufferFF, 8);       执行完上述代码后,对应的地址区间数据没有变化,写入失败,返回错误代码101,如下图所示, 错误代码101看上去有点陌生,这在之前的LPC产品中并不常见,我们在用户手册中搜索FLASH driver status code,可以查找到错误代码101为FLASH 对齐操作错误(Alignment Error)。   对齐操作错误是什么?我们先来看程序是如何对FLASH_Program函数进行定义的。 FLASH写函数定义如下: status_t FLASH_Program(flash_config_t *config, uint32_t start, uint32_t *src, uint32_t lengthInBytes); 新用户经常会忽略掉用户手册中对于这个API的介绍“the required start and the lengthInBytes must be page size aligned”,这句话的意思是在执行FLASH_Program函数时,写入的起始地址和数据长度必须512字节对齐,所以如果我们把代码 status = FLASH_Program(&flashInstance, destAdrss, (uint8_t *)s_bufferFF, 8); 更正为 status = FLASH_Program(&flashInstance, destAdrss, (uint8_t *)s_bufferFF, 512); FLASH_Program函数就可以运行成功。   请注意:在2.6.x版本的SDK中,FLASH_Program函数的注释将参数的起始地址和数据长度错误的表述为字对齐,2.7.0版本的SDK已经对注释进行了修正。即使你想要操作一个字节,lengthInBytes也是512字节对齐。   最后:建议用户在遇到关于FLASH API操作失败的相关问题,一定要查看用户手册中的FLASH驱动状态码,我们可以从UM11126中的第九章节FLASH API部分找到它,如下图所示。  
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经常有客户在使用LPC55S69的过程中遇到读 Flash进入异常HardFault中断的现象。如果在Flash Mass Erase之后从未对Flash扇区进行过写操作,直接用指针通过AHB读Flash地址会导致程序跳入HardFault 中断而无法继续正常运行。 原因    刚出厂的LPC55Sxx FLASH处于全零的全擦除状态,没有设置ECC。当芯片通过LinkServer 和MCUXpresso IDE建立连接时,先擦除要下载代码用到的扇区,再把代码下载到对应位置,并对相应存储区的ECC值同时进行更新。代码以外的区域仍然是无ECC设置的擦除状态。 当LPC55Sxx 通过AHB总线直接读取Flash内存区域时(例如,mytemp = *(uint32_t*)0x4000)要对Flash ECC进行校验。这一指令对于读有效代码区是没有问题的, 因为这一区域的ECC在下载代码时早已设置好。但是一旦读取没有代码的扇区,由于没有检测到正确的ECC,导致Flash读取失败,并跳转到下图中的HardFault_Handler()异常中断:   我们在Sector Erase后通过AHB读取Flash内存内容,也会遇到同样的HardFault异常跳转,出问题的原因都是一样的。 解决方法 针对这一问题我们有如下两种解决方法: 先执行Flash写操作,再读取Flash 与Flash 擦除操作不同,执行Flash写操作后对应的ECC值也同步更新。这样,ECC校验通过后,通过下面的代码就可以对Flash直接进行AHB读取。 volatile uint32_t mytemp; …… mytemp = *(uint32_t*)0x1000;//read memory content 0x1000 to mytemp 请注意:0x1000必须是一个已经写过的地址。 如果Flash的某个扇区处于被擦除的状态,我们只需要在通过AHB总线读取内存区域之前对该区域执行写操作,这样ECC校验位更新正确后,就可以正常读Flash。 Flash的写操作可以参考MCUXpresso SDK自带的flashiap例程,函数FLASH_Program。   使用Flash控制指令读取Flash区内容 使用Flash控制指令进行读操作不会导致硬件错误(请参阅UM11126 “Command listing (CMD)”章节)。这是用户手册中推荐的读Flash正确打开方式。 请注意:CPU只有在频率低于100MHz时,才能进行Flash操作(读,写,擦除,校验,等等),当CPU频率超过100MHz时是不能实现上述操作的。 目前,官方没有提供上用控制指令读取Flash内容的例程,因此需要您根据下面步骤创建自己的读Flash程序。 开发环境: IDE: MCUXpresso IDE v11.1.0 SDK MCUXpresso SDK v2.7.0 步骤: 在MCUXpresso IDE中导入一个基础例程,如led_blinky 在下图所述选项中添加iap组件   选择iap1,点击OK   点击完OK之后,fsl_iap_ffr.h, fsl_iap.c, fsl_iap.h文件将自动添加到工程中   在source文件夹中添加附件中的memory.h和memory.c文件   4) 使用Flash 控制指令时,需要在源文件中添加memory.h, fsl_iap.h   5) 调用memory初始化和memory读取函数   6)调试,单步执行(step over)到memory_read(),查看结果  
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Symptoms Some users cannot access MCU peripherals normally by add peripheral initialization code to MCUXpresso SDK TrusZone demo. For example, when add Flash operation code in the security world, the program code jumps to HardFault_Handler after running to function FLASH_INIT(), and the execution of Flash erase and Flash program operations fails also, as follows: Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Diagnosis As shown in figure 2 and figure 3, when the program code runs to code return VERSION_FLASH_API_TREE->flash_init(config), it automatically jumps to HardFault_Handler. VERSION_FLASH_API_TREE is located in the 0x1301fe00 address of the boot rom, the flash erase api is located in address 0x1300413bU, and the flash program api is located in address 0x1300419dU (the corresponding program code is shown in figure 6). All above addresses are not security privilege. Figure 6        From the 7.5.3.1.2 TrustZone preset data chapter in user manual, after enabling the TrustZone configuration, users must configure the security level of the entire ROM address space to security priority (S-Priv) in order to ensure that the ROM area can be accessed normally by the security area code. Figure 7 Solution Below is the steps of how to resolve this issue. The demo is based on MCUXpresso SDK demo hello_world_s. Step 1: firstly we use the TEE tool integrated with MCUXpresso IDE to configure the security level of the Boot ROM address area, as shown in Figure 8, double-click the Boot-ROM area in the Memory attribution map window, and configure the sector’s security level in the corresponding Security access configuration window on the left. Figure 8 Step 2: Second, when operating Flash or other peripherals in the security area, users must configure the security level of correlative peripherals to the security priority(S-Priv).        When operating flash in the SDK TrustZone demo, the MCU uses two slave peripherals, so users must configure their security level to S-Priv. Figure 9 Please Note: From the usermanual, when operating flash, the system clock frequency cannot exceed 100MHZ. When using the function of FLASH_Program(), because the s_buffer is 512-byte aligned, the BUFFER_LEN is equal to 512/N.   The above configuration of the security level can be configured through the TEE tool integrated the MCUXpresso IDE. After completing configuration, click Update Code to automatically update the relevant code in the tzm_config.c file, as shown in Figure 10. Figure 10 The updated code is shown in Figure 11 below. It is obvious that the security level settings of boot rom memory and peripheral (FLASH, SYSCTRL) have changed. If you do not use the TEE tool, you can also manually modify tzm_config.c to configure the same security options. Figure 11 Third-party tools users: Because many users are accustomed to using third-party development tools such as Keil or IAR, but these IDEs do not integrate the TEE tool, users need to check the configuration requirements of related registers in user manual when modifying the security level of related areas and peripherals in TrusZone, and update the associated code in the tzm_config.c file (similar to Figure 11) to complete the related configuration. In addition, NXP released the MCUXpresso Config Tools, which integrates MCU-related configuration functions. Users can download and install this tool to perform configurations and update codes. The download link is as follows: https://www.nxp.com/design/software/development-software/mcuxpresso-software-and tools/mcuxpresso-config-tools-pins-clocks-peripherals:MCUXpresso-Config-Tools   Introduction of MCUXpresso Config Tools After the tool is installed, open the configuration tool, select Create a new configuration based on an SDK example or hello world project, click Next, as shown in Figure 12: Figure 12   In Start Development window, follow below steps to generate project. As shown in Figure 13. Figure 13 After the tzm_config.c file is updated, copy or import it to the corresponding folder of KEIL or IAR third-party development tools, and it can be used normally.          
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Symptoms Many LPC55 users experienced connection failure when using ISP USB0 for firmware update. In practice, we don’t suggest user updating firmware via ISP USB0 for LPC55(S)6x/ 2x,LPC55(S)1x/0x parts. Diagnosis LPC55 USB0 is Full Speed USB port. The default setting of CMPA turns off the USB0 port. Some users may reconfigure CMPA to enable ISP USB0 in order to use ISP USB0 BOOT, but this is not recommended in practice. LPC55 ISP USB0 uses internal FRO as clock source. According to LPC55 data sheet, the FRO accuracy is only +-2%, while the FS USB data rate tolerance specification is +-2500ppm(+-0.25%). Obviously, the LPC55 FRO spec can’t meet the USB0 clock accuracy requirement. See below extraction from NXP manuals. Fig 1. The accuracy of FRO ( Extracted from LPC55S69 Datasheet )   Fig 2. The accuracy requirement of USB FS( Extracted from TN00063 )  Some users may wonder why USB0 can use internal FRO as clock source in the user application?  Whenever internal clock source FRO is used as USB0 clock source, we must calibrate FRO in source code for communication. That’s to say, trim FRO to an accurate frequency. We can see FRO trim in many MCUXPressoSDK USB demos. When using FRO as the USB0 clock source, in order to ensure the USB0 clock accuracy, we must use the USB0 SOF frame synchronization to calibrate the FRO in order to ensure the accuracy of FS USB clock source (reference design of TN00063, TN00063-LPC5500 Crystal-less USB Solution). Unfortunately, the BOOT ROM of LPC55 does not support USB SOF calibrating FRO. As a result, even if we enable ISP USB0, the FRO clock drift can still cause USB0 communication failure under non-room temperature conditions. Solution Since ISP USB0 is not recommended for firmware update, the user manual no longer announces the enablement bit of ISP USB0 in CMPA. If you need to use USB0 for firmware update, we recommend using ISP USB1 (High Speed USB), because USB1 uses accurate external clock source which can ensure the ISP USB1 working stable. In addition, the communication protocol of ISPUSB complies with BLHOST specification. For details, see:  blhost User's Guide - NXP  
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Some customers want to generate CRC checksum during compile project, while the GUN tool chain in MCUXpresso IDE doesn’t include CRC checksum calculation function, so we need  the help of CRC checksum tools. In this article, use SRecord. About detail theoretical knowledge of SRecord, please refer to https://mcuoneclipse.com/2015/04/26/crc-checksum-generation-with-srecord-tools-for-gnu-and-eclipse/ In this thread, mainly describe the steps about how to generate CRC checksum with MCUXpresso IDE post-build, through a hands on.   Environment: LPC54S018 chip MCUXpresso IDE SRecord tool (http://srecord.sourceforge.net/)   Purpose: Generate and place CRC checksum to 0x10000170 of LPC54s018 after compile project. In image header for LPC540xx devices, the offset 0x10 is crc_value, in LPC54s018 , the address is 0x10000170. so we need save CRC checksum value in  this  place.   Steps: Import SDK demo “led_blinky” into MCUXpresso IDE (Just use this demo to demonstrate).   Enable Compute CRC, because there is one bit in Image header for LPC540xx,Just add “ADD_CRC” or “ADD_CRC =1”, build project.     Can check from S19 file: When choose no CRC computation (no defined “ ADD_CRC “ symbol), the data in address 0x0164 bit0 is 1,   When choose compute CRC, the data in address 0x0164 bit0 is 0,        Download SRecord from http://srecord.sourceforge.net/ After download, srec_cat.exe is the main program we used. Place srec_cat.exe utility in a common directory (to reuse it even if you change the project or even the MCUXpresso IDE version). Be sure you add that “common directory” in the PATH environment variable, then be sure the eclipse was restarted to “see” the PATH content.   Create command file crc_add.txt, and place it under" Debug" folder of project. (About detail commands, please refer to SRecord Reference Manual.) # srec_cat command file to add the CRC and produce application file to be flashed # Usage: srec_cat @filename #first: create CRC checksum lpcxpresso54s018m_led_blinky.srec # input file -fill 0xFF 0x10000180 0x10010000 # fill code area with 0xff -crop 0x10000180 0x10010000 # just keep code area for CRC calculation below (CRC will be at 0x1FFFE..0x1FFFF) -CRC16_Big_Endian 0x10000170 -CCITT # calculate big endian CCITT CRC16 at given address. -crop 0x10000170 0x10000172 # keep the CRC itself #second: add application file lpcxpresso54s018m_led_blinky.srec # input file -fill 0xFF 0x10000180 0x10010000 # fill code area with 0xff -crop 0x10000000 0x10000170 0x10000172 0x10010000 #keep all except CRC #finally, produce the output file -Output # produce output lpcxpresso54s018m_led_blinky_crc.srec   Add post-build command to create srecord file with CRC checksum. arm-none-eabi-objcopy -v -O srec "${BuildArtifactFileName}" "${BuildArtifactFileBaseName}.srec" & srec_cat.exe @CRC_add.txt   7) Build project, the .srec with CRC checksum file will under Debug folder:         Pay attention: For the format of image header of LPC540xx devices, we need enable compute CRC and put the CRC value in the specific address. while for other chips, maybe do not need enable, and also can place it in your own address.   Reference: https://mcuoneclipse.com/2015/04/26/crc-checksum-generation-with-srecord-tools-for-gnu-and-eclipse/        
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There are two ways to program LPC chips using Flash Magic, ISP mode and  Single Wire Debug (SWD) mode. ISP mode support COM port, USB, CAN and Ethernet. SWD support LINK2(LPC1800/lpc4300) bridge and LPC11u35 bridge. This article uses four demonstrations to show these programming methods.   1. ISP mode   1.1 UART ISP Mode Demonstration   1.2 USB ISP Mode Demonstration 2. Single Wire Debug(SWD) Mode   2.1 SWD over Link2 Bridge     2.1.1 Introduction     2.1.2 Demonstration  2.2 SWD over LPC11U35    2.2.1 Introduction    2.2.2 Demonstration    2.2.3 Recover board   Download Flash Magic tool from: https://www.flashmagictool.com/ Pay attention use the new version Flash Magic v13.10 or later.   About detail steps please refer to attachment. Thanks!
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This document describes the different source clocks and the main modules that manage which clock source is used to derive the system clocks that exists on  LPC’s devices. It’s important to know the different clock sources available on our devices, modifying the default clock configuration may have different purposes since increasing the processor performance, achieving specific baud rates for serial communications, power saving, or simply getting a known base reference for a clock timer. The hardware used for this document is the following: LPC: LPCXpresso55S69 Keep in mind that the described hardware and management clock modules in this document are a general overview of the different platforms and the devices listed above are used as a reference example, some terms and hardware modules functionality may vary between devices of the same platform. For more detailed information about the device hardware modules, please refer to your specific device Reference Manual. LPC platforms The System Control Block (SYSCON) facilitates the clock generation in the LPC platforms, many clocking variations are possible and the maximum clock frequency for an LPC55S6x platform is @150MHz. For example, the LPC55S69 device supports 2 external and 3 internal clock sources. ·    External Clock Sources   Crystal oscillator with an operating frequency of 1 MHz to 32 MHz.   RTC Crystal oscillator with 32.768 kHz operating frequency.   ·    Internal Clock Sources Internal Free Running Oscillator (FRO). This oscillator provides a selectable 96 MHz output, and a 12 MHz output (divided down from the selected higher frequency) that can be used as a system clock. These 96MHz and 12MHz output frequencies come from a Free Running Oscillator of 192MHz. The 12MHz output provides the default clock at reset and provides a clean system clock shortly after the supply pins reach operating voltage. Note that the 96MHz clock can only be used for a USB device and is not reliable for USB host timing requirements of the data signaling rate.  32 kHz Internal Free Running Oscillator FRO. The FRO is trimmed to +/- 2% accuracy over the entire voltage and temperature range. This FRO can be enabled in several power-down modes such as Deep-Sleep mode, Power-Down mode, and Deep power-down mode, also is used as a clock source for the 32-bit Real-time clock (RTC).  Internal low power oscillator (FRO 1 MHz). The accuracy of this clock is limited to +/- 15% over temperature, voltage, and silicon processing variations after trimming made during assembly. This FRO can be enabled in Deep-Sleep mode, used as a clock source for the PLL0 & PLL1, and for the WWDT(Windowed Watchdog Timer). The LPC55S69 can achieve up to 150MHz but the clock sources are slower than the final System Clock frequency (@150MHz), inside the SYSCON block two Phase Loop Locked (PLL0 & PLL1) allow CPU operation up to the maximum CPU rate without the need for a high-frequency external clock. These PLLs can run from the Internal FRO @12 MHz, the external oscillator, internal FRO @1 MHz, or the 32.768 kHz RTC oscillator. These multiple source clocks fit with the required PLL frequency thanks to the wide input frequency range of 2kHz to 150 MHz. The PLLs can be enabled or disabled by software. The following diagram shows a high-level description of the possible internal and external clock sources, the interaction with the SYSCON block, and the PLL modules.    Figure 1. General SYSCON diagram   SYSCON manages the clock sources that will be used for the main clock, system clock, and peripherals. A clock source is selected and depending on the application to develop the PLL modules are used and configured to perform the desired clock frequency. Also, the SYSCON module has several clock multiplexors for each peripheral of the board i.e(Systick, FullSpeed-USB, CTimer), so each peripheral can select its source clock regardless of the clock source selection of other peripherals. For example, the following figure shows these described multiplexers and all the possible clock sources that can be used at the specific module.  Figure 2. Source clock selection for peripherals   For more detailed information, refer to “Chapter 4. System Control (SYSCON)” from the LPC55S6x User Manual.  Example: Enabling/Disabling PLLs The Clock tools available in MCUXpresso IDE, allows you to understand and configure the clock source for the peripherals in the platform. The following diagram shows the default PLL mode configured @150MHz, the yellow path shows all the internal modules involved in the clock configuration. Figure 3. Default PLL mode @150MHz at Reset of LPC55S69   For example, you can use the Clock tools to configure the clock source of the PLL to use the clk_in coming from the internal 32MHz crystal oscillator, the PLL is configured in bypass mode, therefore the PLL gets inactive resulting in power saving. Figure 4. Bypass of the PLL For more detailed information about PLL configuration, refer to “Chapter 4.6.6. PLL0 and PLL1 functional description” from the LPC55S6x User Manual.  Example: The next steps describe how to select a clock source for a specific peripheral using Clock Tools. 1.1 Configure clock for specific peripheral To configure a peripheral as shown in figure 17, Clock Tools is also useful to configure the clock source for the desired peripheral. For example, using the CTimer0 the available clock sources are the following: Main Clock PLL0 Clock FRO 96MHz Clock  FRO 1MHz Clock MCLK Clock  Oscillator 32KHz Clock No Clock(Inactive)                  Figure 5. CTimer0 Clock Source Selector Select CTIMERCLKSEL0 multiplexor and then switch to one of the mentioned clock sources, for example, the main_clk(Main Clock @150MHz) the clock multiplexor gets active and the yellow path is highlighted as shown in the following image.    Figure 6. CTimer0, Main Clock attached 1.2 Export clock configuration to the project After you complete the clock configuration, the Clock Tool will update the source code in clock_config.c and clock_config.h, including all the clock functional groups that we created with the tool. This will include the clock source for specific peripherals. In the previous example, we configured the CTimer0 to use the main_clk; this is translated to the following instruction in source code: “CLOCK_AttachClk(kMAIN_CLK_to_CTIMER0);” inside the “BOARD_BootClockPLL150M();” function.                      Figure 7. API called from clock_config.c file Note. Remember that before configuring any internal register of a peripheral, its clock source needs to be attached, otherwise, a hard fault occurs. References LPC55S6x/LPC55S2x/LPC552x User Manual Also visit RT's System Clocks Kinetis System Clocks
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Introduction Amazon Web Services (AWS) is the world’s most comprehensive and broadly adopted cloud platform, offering over 165 fully-featured services from data centers globally. Millions of customers —including the fastest-growing startups, largest enterprises, and leading government agencies—trust AWS to power their infrastructure, become more agile, and lower costs.This document will take you step-by-step in a simple approach to adding peripherals to your AWS IOT and Alexa skills project. This is in continuation of the demo established in the following link, it is important to have this completed before continuing with this guide: Connecting the LPC55S69 to Amazon Web Services  Prerequisites - LPC55S69-EVK - Mikroe WiFi 10 Click - AWS Account - Alexa Developer Account - MCUXpresso IDE 11.2 - LPC55S69 SDK 2.8.0 Modifying "AWS_REMOTE_CONTROL_WIFI" In this example I will be adding a single-ended ADC peripheral. 1. First, create a separate .c and .h files in my source folder to keep it organized.  2. Initialize your peripheral. This includes your global variables, pins, clocks, interrupt handlers and other necessary peripheral configurations yours may have.  In my new_peripherals.c file, I add the following 2.1 Definitions: 2.2 Global variables: 2.3 Interrupt handler: 2.4 Initialization function: 2.5 Read ADC Function: 3.  Create header file with the two functions that will be used to enable the ADC, make sure to include the "fsl_lpadc"drivers. 4.  Add the ADC pin with pin configuration tool.  4.1 In this example I use PIO0_23 for the ADC0 Channel 0, 5. Add ADC_Init function to the main. 6. Now let's go ahead and modify "remote_control.c". Here we need to build the JSON text that we want updating our Thing's shadow with the ADC value, add the read function, add the variable in the initial shadow document and the keyword for our DeltaJSON. 6.1 First create global variables for the actual state of the ADC interaction and the parsed state. 6.2 Add external function which will read the ADC value. 6.3 Shadows use JSON shadow documents to store and retrieve data. A shadow’s document contains a state property that describes these aspects of the device’s state: desired: Apps specify the desired states of device properties by updating the desired object. reported: Devices report their current state in the reported object. delta: AWS IoT reports differences between the desired and the reported state in the delta object. 6.4 I've added the initial ADC state with a hard-coded 0, so that I can verify my Thing's shadow is initialized with the new information. 6.5 In the "void processShadowDeltaJSON(char *json, uint32_t jsonLength)" function, we need to add the condition for the change in state of the ADC. This will helps us identify when the action to read the ADC is requested. 6.6 Finally in the "prvShadowMainTask" function, we will create the action based on the above request. We can add some PRINTFs so that we know that the action is requested and processed properly through the serial console. As you may see I only want to update the ADC value when it is requested. Meaning the value of the ADC's state or parsed state is important. We will clear it to zero after we read the ADC and only update the value when it is 1. As opposed to the LEDState and parsedLEDState, where the value is important since it points to which color LED will be on/off. That's it you can build and run the project! Now we can add the Alexa Skill and the functionality in the AWS Lambda. MODIFYING AWS LAMBDA Since the lambda will be the connection between our LPCXpresso board and the Alexa Skill, we need to add the handler for  our new ADC requests. 1.  In this example we add the third request type which is the ADC event and the name of the callback function we will use.  2. The callback function "manage_ADC_request" will contain the attributes for reading and updating the shadow, this will consequently cause the change in delta shadow so our LPC55S69 will read the ADC pin. In addition, the utterances sent to the Alexa skill as well as how we want Alexa to respond will also be defined here.  As you may observe our function builds the JSON payload to update the shadow with a "1" when it is called and ignores the led and accelerometer values. We delay for 2.5 seconds to allow the LPC to read and write the ADC value in the necessary field and send the updated shadow. Then the Lambda will read the shadow and create the return message.  With this we construct the answer for Alexa. MODIFYING ALEXA SKILLS 1.  First create a custom 'intent'. Here is the general definition of what the utterances will be to request an action from the AWS Thing.    1.1 The name needs to match the name used for the event in the Lambda. In this example it is ADC_INTENT 2. Before we create the utterances, let's create the slot types. This is the list of all the words possible that may come to mind that a user might say to request a reading from the ADC.  2.1 The name of the slot type is not crucial, however please note it as we will need it later.  2.2 Add slot values. You can add as many as you think are necessary. For recommendations on custom slot values please check, best practices for sample utterances. 2.3 Go back to the general view of the ADC_INTENT, scroll down and we will add how the slot will be included in the utterances. In this example I use adc_name, however the name here is also not crucial. Select the slot type list we created earlier. 2.4 Now scroll back up and lets begin adding the sample utterances. This can be any command that you believe a user can say to invoke this action. You do not need to include the wake word here. In brackets add the name of your intent slot, in this case it is {adc_name}. That's it! You can save and rebuild the model. You are now ready to test it. You can do so through the 'Test' tab on the developer's console. In addition if you have an Alexa device or the SLN-ALEXA-IOT, you can test it by speaking with Alexa directly. In your LPCXpresso55S69 you can connect the 3.3V or the 0V to the ADC pin so you can see how the value is returned every request. 
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This article introduces how to create a custom board MCUXpresso SDK and how to use it, mainly includes three parts: Part1: Generating a Board Support Configuration (.mex) Part2: Create a Custom Board SDK Using the Board SDK Wizard Part3. Using the Custom SDK to Create a New Project   Requirements: MCUXpresso IDE v11.1.1, MCUXpresso SDK for LPC845, LPC845-BRK board. This method works for all NXP mcu which support by MCUXpresso SDK. About detail steps, please refer to attachment. Thanks!
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The following document contains a list of documents, questions and discussions that are relevant in the community based on the amount of views they are receiving each month. If you are having a problem, doubt or getting started in LPC or MCUXpresso you should check the following links to see if your doubt have been already solved in the following documents and discussions. MCUXpresso MCUXpresso Supported Devices Table  FAQ: MCUXpresso Software and Tools  How to create a new LPC project using LPCOpen and MCUXpresso IDE  Introducing MCUXpresso SDK v.2 for LPC54xxx Series  Generating a downloadable MCUXpresso SDK v.2 package  Using the MCUXpresso Pins Tool   MCUXpresso Config Tools is now available!   LPC55xx Multicore Applications with MCUXpresso IDE  LPC information LPC5460x MCU Family Overview  USB with NXP Microcontrollers LWIP memory requirements  LPC800 Four-Part Webinar Series!  The LPC804 Programmable Logic Unit (PLU)   LPC84x Technical Training - Now Available Guides and Examples Flashing and Installing the new firmware and drivers for LPC11U35 debug probes  Enabling debug output  USB FLASH download, programming, and security tool (DFUSec)  DMA Ping-Pong application  Getting start with LPCXpresso54608 & emWin Graphics;  Capacitive Touch example using the LPC845 Breakout Board  OLED Display Application Example using LPC845 Breakout Board and SPI  Mixed-Signal Logic Analyzer & Oscilloscope (Lab Tool) Solution  LPC FAQ How to calculate the value of crystal load capacitors? Can I send a message with X/Y/Z bits in the ID?  What is the difference between error active and error passive? What is the sample point for?  How can I verify the configured CAN bitrate, using an oscilloscope? 
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