t0.txt="hello"<\/pre><\/div>\n\n\n\nYou should see something similar:<\/p>\n\n\n\nNow, press on hex:<\/p>\n\n\n\n
<\/p>\n\n\n\nYou will get the equivalent hex format to t0.txt=”hello” and extra 3 0xFF which indicate the end of the command. This shall be sent at the end of each string in our code.<\/p>\n\n\n\n
Now, insert an SD-Card to your computer and generate TFT file to load it to our display:<\/p>\n\n\n\nAfter that, select your SD-Card:<\/p>\n\n\n\nPress on output to copy the file to SD-Card.<\/p>\n\n\n\n
Now, insert the SD-Card into your Nextion display:<\/p>\n\n\n\n
<\/p>\n\n\n\n
You should see a message on the display saying the code is being uploaded.<\/p>\n\n\n\n
When it is ready, it should display the following message:<\/p>\n\n\n\n
Remove the power from the Nextion display, and unplug the microSD card.<\/p>\n\n\n\n
<\/p>\n\n\n\n
After than, you should see newtxt is being displayed on the screen. This is the end of step one.<\/p>\n\n\n\n
<\/p>\n\n\n\n
2. STM32F4 Setup:<\/h2>\n\n\n\n <\/p>\n\n\n\n
The function that will send the string to Nextion display shall take two arguments:<\/p>\n\n\n\n
First one character pointer to the id.<\/li> Second one character pointer to the string to be sent.<\/li><\/ul>\n\n\n\nvoid nextion_write_text(char *id,char * p)<\/pre><\/div>\n\n\n\nInside the function, we declare character array of 5 to hold the data:<\/p>\n\n\n\n
char buf[50];<\/pre><\/div>\n\n\n\nThen using sprintf, we shall combine the id and the string into single character array:<\/p>\n\n\n\n
sprintf(buf,"%s.txt=\\"%s\\"",id,p);<\/pre><\/div>\n\n\n\nSend the buffer:<\/p>\n\n\n\n
send_uart(buf);<\/pre><\/div>\n\n\n\nWrite the 3 0xFF:<\/p>\n\n\n\n
\tuart1_write(0xFF);\n\tuart1_write(0xFF);\n\tuart1_write(0xFF);<\/pre><\/div>\n\n\n\nHence, the entire function as following:<\/p>\n\n\n\n
\nvoid nextion_write_text(char *id,char * p)\n{\n\tchar buf[50];\n\tsprintf(buf,"%s.txt=\\"%s\\"",id,p);\n\tsend_uart(buf);\n\tuart1_write(0xFF);\n\tuart1_write(0xFF);\n\tuart1_write(0xFF);\n\n}\n<\/pre><\/div>\n\n\n\nIn main function:<\/p>\n\n\n\n
#include "delay.h"\n#include "string.h"\n#include "nextion_uart.h"\n\n\/*Nextion Buffer size*\/\n#define NEXTION_BUFF_LENG 10\nvolatile char NEXTION_BUFF[NEXTION_BUFF_LENG];\nvolatile uint32_t itr;\n\nchar data_send[10];\nuint8_t counter;\nint main(void)\n\t{\n\tSCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2));\n\tsystick_init_ms(16000000);\n\tnextion_uar_init(115200,16000000);\n\n\twhile(1)\n\t\t{\n\t\tsprintf(data_send,"Count=%d",counter++);\n\t\tnextion_write_text("t0",data_send);\n\t\tdelay(100);\n\t\t}\n\t}\n<\/pre><\/div>\n\n\n\nNote: my Nextion display works with 115200 baudrate.<\/p>\n\n\n\n
<\/p>\n\n\n\n
3. Demo:<\/h2>\n\n\n\n <\/p>\n\n\n\n
![\"\"](\"https:\/\/m.media-amazon.com\/images\/S\/abs-image-upload-na\/9\/AmazonStores\/ATVPDKIKX0DER\/4551205750cd023df17bdecd5dbbb3ee.w400.h400.jpg\")
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<\/figure>\n\n\n\n![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/12\/nextion-micro-sd.jpg?resize=501%2C265&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n\n![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/12\/copy-sd-card-nextion.jpg?resize=501%2C271&quality=100&strip=all&ssl=1\")
<\/figure><\/div>\n\n\n\n![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/12\/upload-success-nextion.jpg?resize=700%2C303&quality=100&strip=all&ssl=1\")
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