Progmem esp32 If it does cause problems, you will need to change to code to remove PROGMEM and related function calls. Sep 24, 2019 · I am working with a Raspberry Pi4 and the ESP8266. exe and same result. An easy way of accessing any type of data in PROGMEM is to use this small library: PROGMEM_readAnything. This document describes using ESP-IDF with the ESP32 SoC. Instruction memory is executable, and can only be read or written via 4-byte aligned words. However, this is unnecessary, as any const declared data are kept in Flash anyway. h aren't being placed in PROGMEM properly Hardware WiFimanager Branch/Release: Master Esp8266/Esp32: ESP8266 Hardware: ESP-12e Core Version: 3. The TMRpcm does not work and seams very old. I have successfully hardcoded this data using: byte dat[] PROGMEM = {1,2,3,4}; But i now want to be able write to flash after compilation so i believe that I must use the EEPROM library. This same new Uint8_t array[] PROGMEM I'm using so that the Bodmer <JPEGDecoder. 3" 240x240 Wide Angle TFT Product ID: 4313 Feb 8, 2021 · HI there. cpp file? Nov 6, 2018 · Learn how to use the ESP32 flash memory to store permanent data. В МК обычно представлен Flash Mar 19, 2020 · Hi all, I'm hoping someone can help here as I've been stuck on this for some time. In this Instructable, you will be displaying icons or logos or images on your TFT screen from Arduino with using ATmega (microcontroller used in Arduino) Flash mem… Jan 8, 2021 · I am using ImageConverter 565 and realizing that a 5k jpg turns into 1. h file. I'm capturing images with Esp32CAM and transferring them via ESP-NOW to another Esp32 Wroom. This might be useful if you want to delete any changes made to the firmware or configuration settings. The HTML page is static and defined in PROGMEM as a raw string literal. My Arduino Nano has run out of SRAM space and I'm trying to move some string constants to program memory / flash from RAM. After that, a simple example will show you how to use ESP-IDF (Espressif IoT Development Framework) for menu configuration, then for building and flashing firmware onto an ESP32 board. Data memory is not Mar 17, 2022 · I am a barely adequate C programmer with no knowledge of HTML. I also have connected an LM386 to the digital pin D9. h file and it is just a long array of hex #ifndef PROGMEM #define PROGMEM #endif const uint8_t dragon_optimized[] PROGMEM = { 0x47,0x49,0x46 Jan 13, 2018 · Hello, I'm trying to get my ESP32 to output an 8-bit 16-kHz sound file that is stored in PROGMEM as uint8_t via I2S, through an Adafruit I2S mono amp. Feb 11, 2021 · The sketch below currently works by converting a bmp into an array using this conversion tool lcd-image-converter download | SourceForge. The tests of this… Dec 16, 2017 · To finalize the global declarations, we will create a variable in the PROGMEM that will contain the HTML code we have prepared. ESP-IDF distinguishes between instruction memory bus (IRAM, IROM, RTC FAST memory) and data memory bus (DRAM, DROM). I have 3 html pages and I would like the same logo to be present on every page. If file #2 is a . Aug 26, 2023 · I have a arduino nano esp32 connected to an sd card modul and can read wav files. Still, what is it you are planning to do that will require that much ? Jul 21, 2025 · 本文介绍了如何在Arduino框架下使用PROGMEM功能将字符串和数据存储到ESP32/8266的Flash中，包括宏定义、存储与回读技巧，以及FPSTR和F ()的使用对比。 The objective of this ESP32 Arduino Tutorial is to explain how to serve a simple HTML page from the ESP32, using the Arduino core. Web Server examples by using ESPAsyncWebServer (for ESP32 and ESP8266) and ESP8266WiFi (for Aug 16, 2017 · Espressif ESP32 Official ForumThe purpose of Preferences is entirely different from Progmem. So. Jul 24, 2021 · PROGMEM is the keyword you use when you wish to store data in the program memory (flash) instead of the SRAM. h or . Which is just fine when there is a relatively small amount of PROGMEM data, but doesn't make sense at all if you KNOW that there is going to be more than 64k of PROGMEM. I would like to write relatively large amounts of data(100kb) to the esp32 internal flash . Postby MicroController » Wed Dec 27, 2023 10:18 am Feb 15, 2024 · To perform an ESP32 factory reset, we’ll use esptool, which is “ a Python-based, open-source, platform-independent utility to communicate with the ROM bootloader in Espressif chips. What's reputation and how do I get it? Instead, you can save this post to reference later. A web server request handler to support generated PROGMEM contents and GZIP compression. OTOH, declaring the data as const together with PROGMEM works, in the sense that it doesn't get counted in "dynamic memory". 8w次，点赞62次，收藏212次。博客围绕AVR系列单片机存储器展开，指出编译Arduino程序时动态内存不足问题。介绍使用PROGMEM关键字或数据类型，将常量存入程序存储空间以节约动态内存。还阐述了数据定义、读取方法，以及相关处理函数、F ()宏的使用，和Flash寻址宏的选择。 Aug 12, 2023 · For one application, because of exactly that problem of using PROGMEM for large data structures, I moved it from a Mega to an ATmega4809 based Nano Every instead. To switch to a different SoC target, choose target from the dropdown in the upper left. See this recent thread, for example What does a variable in between % signs means? %VARIABLE% - Programming Questions - Arduino Forum Personally, I prefer 6v6gt's method using static HTML with XMLHttpRequest requests in Mar 10, 2018 · You'll need to complete a few actions and gain 15 reputation points before being able to upvote. Progmem provides a way to store immutable data in program memory (which is usually Flash), instead of data memory (which is usually DRAM). h> #include "BluetoothSerial. Espressif has made a significant effort to port the ESP32 Core to Arduino so that it is very similar to programming a conventional Arduino. h:13:25: error: expected initializer before 'PROGMEM' Should I include something or can't I use PROGMEM in a . This method is particularly useful for serving static content like HTML, CSS, or JavaScript files efficiently, as it leverages the flash memory of the ESP32 to Sep 24, 2024 · This is a code sample to illustrate the use of ESPAsyncWebServer together with an HTML form, json for transferring data to the browser and ESP32 Preferences for persistent storage of configuration data. ESP-IDF is the official development framework for the ESP32, ESP32-S, ESP32-C, ESP32-H and ESP32-P Series SoCs. Update: As explained in this blog post, in the ESP32 constant data is automatically stored in FLASH memory and can be accessed directly from FLASH memory without previously copying it to RAM. h> #include <WiFi. This post explores practical strategies for optimizing FLASH memory usage in embedded systems when programming in C/C++. Memory Types [中文] ESP32 chip has multiple memory types and flexible memory mapping features. An arduino library to create html string in the sketch for ESP8266/ESP32 WebServer. PROGMEM on a ESP32 is actually only a dummy, kept for code compatibility. aspxARDUINO TIPS #12: Como usar PROGMEN y F() Macro - SRAM - E Oct 26, 2020 · Here a little tutorial to learn how to manage a complete web server via esp8266 esp32 or other arduino like device. For the ESP8266 use board Core 2. Feb 24, 2025 · Hi John, I'm working on a project for a while now. Oct 9, 2019 · A lot of them have to do with my use of PROGMEM for storing individual and array constants (about 14KB worth) in flash on the AVR. Best for Arduino, STM32, ESP32. To write data to the flash memory, you use the EEPROM. What are the positive and negative consequences of storing large variables in Flash ( Sep 7, 2023 · My issue here is the image draws very slowly, I can see the line of pixels coming down the screen and it just wouldn't work to simulate a GIF. The PROGMEM keyword is a variable modifier, it tells the compiler “put this information into flash memory”, instead of into SRAM, where it would normally go. Mar 17, 2022 · Concatenate PROGMEM strings Postby Pelleren » Thu Mar 17, 2022 3:00 am Hi, I'm building a simple web interface to a simple ESP32 application to learn about the ESP32 WROOM processer. it should be in the format of something Jan 10, 2023 · Hey, I’m trying to understand PROGMEM. The problem im having is that i am unable to use the full amount of flash because it seems that the maximum Jan 14, 2025 · Platforms like Arduino and ESP32 often have limited FLASH memory, making it essential to optimize its usage for efficient and reliable operation. May 12, 2025 · Smart hardware solutions based on ESP32ESP-IDF Programming Guide This is the documentation for Espressif IoT Development Framework (esp-idf). When the JPG array arrives in the second ESP32 Wroom as char array[], I'm converting it again to Uint8_t array[] PROGMEM. Converts images to uint32 and uint8 variables for Adafruit GFX, u8g2 and TFT_eSPI ESP32 WiFi Ultimate Guide. Mar 17, 2025 · Home / References / ESP32 Library / WebServer Library Description The send_p() method is a powerful function in the ESP32 WebServer Library that allows you to send HTTP responses containing data stored in PROGMEM (Program Memory). The output state is HIGH when you keep holding the button and it changes to LOW when you release it. Wondering what I am doing wrong? hello. I want to store things like wifi ssid, password, API keys, server name (for ThingSpeak) etc in flash and access them locally in the function vs being globally defined. h> library can read it and finally print it on the Jun 29, 2019 · Nope, see EDIT2 above, and the memory sizes reported by the compiler. I am using a generic example of toggling a LED, but running into an issue It seems there are issues with the compiling of const char MAIN_page[] PROGMEM = R"=====( when running on Windows vs MAC, but there is no mention of Linux below is the code and below that is the result from the serial print IT seems to tell me I called the webpage, but Arduino PROGMEM用法及代码示例请注意，由于 PROGMEM 是一个变量修饰符，因此对于它应该去哪里没有硬性规定，因此 Arduino 编译器接受以下所有定义，它们也是同义词。然而，实验表明，在各种版本的 Arduino 中 (与 GCC 版本有关)，PROGMEM 可能在一个位置而不是在另一个位置工作。下面的"string table" 示例 Dec 24, 2023 · Espressif ESP32 Official ForumRe: looking for audio dictionary words code as PROGMEM : year, month, day. Can you please specify which tool did you use to create the EagleEye, Baboon40, etc. 9, . The code does everything I want but writes the image to a ESP32 is a series of low-cost, low-power system on a chip microcontrollers with integrated Wi-Fi and Bluetooth. What worked before in the Ino sketch is: const uint8_t _red[] PROGMEM = { 0, 9, 10, 220, 230, 240, 255 }; But when I put the line above in a . Now I receive an invalid format. It simply tells the program to allocate a declared variable in program memory space instead of in RAM. h #include <Arduino. May 20, 2020 · The PROGMEM keyword is a variable modifier, it tells the compiler to "keep this variable in flash memory", instead of loading it into SRAM. Since I am using only numbers (0. There are so many variants that i am personally confused, but i have versions that suffice for what i want them to do. In this article, we will see how to program an * ESP32 with the Arduino environment, and the differences between programming an ESP32 and an Arduino. Nov 27, 2018 · - The ESP32 has a version with 2MiB of flash in the same package, but it's a separate die that's still connected in the same fashion as an external flash chip would be. It should be ignored on modern processors, and not cause problems. Learn how to use ESP32 generate audio sound, from a single beep sound to recorded audio, how to program ESP32 step by step. h 文件中包含常量 # Apr 3, 2024 · PROGMEM is useful only with older Arduinos that use ATmega processors, like the Uno. es/orderonline. May 14, 2024 · I need to reduce the size of my esp32 program have no clue how #include <esp_now. 3. , ,) , how can I convert the numeric characters only instead all characters from the particular font file? My last solution will be edit the font file and remove all characters except the numbers, But is there any easier way to achieve this Jul 26, 2018 · Hello, I could not use the existing tools online and offline to convert JPG files into the PROGMEM array. Oct 16, 2019 · The Arduino pages are full with recommendations on using PROGMEM to keep const data in Flash. 5 Description Moving strings into PROGMEM is essen Aug 29, 2019 · Learn how to create an ESP32/ESP8266 web server with three input fields (HTML form) to pass values to your ESP using Arduino IDE. Converting Images to Flash Memory Icons/images for TFT (without SD Card): Many times to make any user interface or nicely display content, we use icons/images. Get Started [中文] This document is intended to help you set up the software development environment for the hardware based on the ESP32 chip by Espressif. As such, something marked as ' [static] const char' doesn't need to be copied to RAM if you only use it in a read-only fashion. Here, constants are automatically assigned to flash by the compiler without the user have to explicitly use PROGMEM. All works fine. h Memory Types [中文] ESP32 chip has multiple memory types and flexible memory mapping features. h" // Include BluetoothSerial header #pragma GCC optimize ("Os") const char deviceName[] PROGMEM = "ESPMaster"; const unsigned long bluetoothTimeout = 5000; // 5 seconds unsigned long lastActivityTime = 0; BluetoothSerial SerialBT; // Declare Mar 9, 2020 · Let's say that there are three files and a main sketch. I tried using the commands provided in the Arduino reference here on this web page, but they just don't seem to work with the ESP32 and the May 24, 2022 · "lcd-image-converter "can we use this software? if yes please can you tell me the process? thanks. While you can use PROGMEM for a single variable, it won't make much sense to do so. Dec 28, 2024 · Nope you will have to google all the info. Feb 19, 2021 · ESP8266 compiler issues using R () rawliteral within PROGMEM F () Projects Networking, Protocols, and Devices ornea February 19, 2021, 10:41am. So, there is no need to use the PROGMEM keyword below and it is only defined Preserve the file name and file path so that the web server can serve the files with relative path. May 20, 2024 · Browse through hundreds of tutorials, datasheets, guides and other technical documentation to get started with Arduino products. On ESP32 processors this is implmented with the help of the Virtual filesystem (VFS) On mbed based implementations we implmenent a FileSystemLike subclass. Oct 18, 2023 · Hey everyone! I am working on a project that uses a ESP32 to display some image on a TFT and it works great since I am putting my image in a header file and in PROGMEM but I want to be able to query a server for this data instead. Nov 1, 2020 · Learn the foundations of the I2S communication with the ESP32 and build projects starting to record sound with a microphone and play WAVE files from an SD card. Then, you can use those values as variables in your code. Equally hotly advised is the use of the F () macro Guide to PROGMEM on ESP8266 and Arduino IDE Intro PROGMEM is a Arduino AVR feature that has been ported to ESP8266 to ensure compatibility with existing Arduino libraries, as well as, saving RAM. Description An array is a collection of variables that are accessed with an index number. On the esp8266 declaring a string such as const char * xyz = "this is a string" will place this string in RAM, not flash. progmem) is intentionally loaded "early" in the memory so that it will be in the bottom 64k where it is easy to reach with pgm_get_byte () and similar. Related Posts ESP32 Arduino HTTP server: Running multiple server instances ESP32 Arduino HTTP server: Getting query parameters ESP32 Arduino async HTTP server: Serving a HTML page from PROGMEM ESP32 Arduino async HTTP server: Serving HTML ESP32 Arduino: Asynchronous HTTP webserver Mar 2, 2023 · Learn how to erase the ESP32 flash memory to restore it to its original state. File #3 includes file #1 and file #2. 0. Store data in flash (program) memory instead of SRAM. This is useful when dealing with large arrays of constant data like lookup tables and strings. Mar 21, 2024 · Hi, While I stumbled from one I2S lib to another: XT_I2S doesn't work (sounds are distorted/chopped) ESP8266audio doesn't make it too easy to play different sound on a press of a button, though it works pretty good with a single PROGMEM audio. This section describes how ESP-IDF uses these features by default. The EPD display looks for an unsigned char array to represent a bitmap. Sep 8, 2024 · Hi I am converting a ttf font file to hex array code, then using it on a display connected to ESP32. I came across the slim variant made by "honey the codewitch" but got another obstacle right in front of me, my LOLIN D32 got no PSRAM/SPIFF option so I Mar 31, 2018 · Progmem ? Postby arnold. Contribute to me-no-dev/ESPAsyncWebServer development by creating an account on GitHub. cpp file I get the error: Par. The main sketch includes #2 and #3. h> // for type definitions template <typename T> void PROGMEM_readAnything (const T * sce, T& dest) { memcpy_P (&dest, sce, sizeof (T)); } template <typename T> T PROGMEM_getAnything (const T * sce) { static T temp; memcpy_P (&temp, sce, sizeof (T)); return temp; } You Mar 18, 2016 · The PROGMEM stuff (. I am trying to modify some code that reads a thermal image from a MLX90640. Build a Web Server with a momentary switch to control the ESP32 or ESP8266 outputs. PageBuilder is an Arduino library class dedicated to the ESP8266WebServer or the WebServer(ESP32) for easily generating HTML pages and sending them to the client. PROGMEM или PGM(program memory, память программы) - собственно постоянная память, в которой хранится исполняемый код программы, он попадает туда во время прошивки и не меняется в процессе работы. Get Started With ESP32 WiFi Jan 6, 2018 · Figure 1 – Output of the alert window, after submitting the form. __FlashStringHelper is only needed to fool C++ into calling the proper version of print () The F () macro contains additional magic to put the literal string into PROGMEM that isn't needed if you've put it there yourself; it might be worthwhile creating a new macro (FV for "Flash Variable"?) to make things prettier: Storing constants in flash on ESP32 - Using Arduino / Programming Questions - Arduino Forum - Concatenate PROGMEM strings - ESP32 Forum 在 . Data memory is not Oct 21, 2025 · 文章浏览阅读2. Learn PROGMEM example code, reference, definition. Apr 14, 2023 · Basic Infos string arrays in wm_consts_en. The image converter doesn't have much options I have seen examples from TFT_ESPI lib and the images are more complex than mine but they are really light in terms of size. Equally hotly advised is the use of the F () macro Some useful NodeMCU32S (ESP32) code snippets. I'd like to store them in flash on the ESP32, but it looks like PROGMEM isn't the way to do it. Have someone an example for me to play a wav file from the nano esp32. esServicio PCB estándar: https://www. Is there a way to draw images quickly to simulate a GIF from an image in PROGMEM? Hardware: QT PY ESP32-PICO Screen: Adafruit 1. The reason behind it, as I had learned, has to do with von Neumann vs. Feb 15, 2018 · I've been trying to find a sufficient way to store, webfiles on the ESP both for the ESP32 and ESP8266. h /. That fixed the stack overflow error. ESP32 boards have significantly more memory and some can have PSRAM. . I've tried a few different things so fare: Storing the files in SPIFFS, but was to slow to retrieve the data, and then timed out Typing the HTML in a simple char array in progmem, but was too pain full process to keep updating it, for every single change in webfiles I then came by Aug 29, 2022 · I'm trying to transfer a monochrome ~4kb image file over WebBT to an ESP32 via BLE. h const char MAIN_page[] PROGMEM = R"=====( <!DOCTYPE html> <html> some With large amounts of text variables, I've found it necessary to store them in the Flash memory using PROGMEM. Async Web Server for ESP8266 and ESP32. IN the meantime that application is now ona an ESP32. h> #include <pgmspace. But i find no way to play a wav file. h file containing something like a font, of the format: const char foo[] PROGMEM = {0xDE,0xAD,0xBE,0xEF}; Then I get linker errors of multiple definitions of 'foo' in both #3 and main. The detail instruction, code, wiring diagram, video tutorial, line-by-line code explanation are provided to help you quickly get started with ESP32. de » Sat Mar 31, 2018 11:37 pm Apr 18, 2025 · Program your ESP32 using PlatformIO and Visual Studio Code! Installing PlatformIO, writing your first sketch, and uploading it to your ESP32. It is possible to place a String into flash, and then load it into RAM when it Arduino core for the ESP32. 5mb . Since ESP-IDF support within PlatformIO is not maintained by the Espressif team, please report any issues with PlatformIO directly to its developers in the official Contribute to aws-samples/aws-iot-esp32-arduino-examples development by creating an account on GitHub. Generic esp8266 module and other representatives Compressing Large HTML,CSS,JS files in ESP Progmem Postby Gheotic » Thu Feb 15, 2018 10:36 am @MaximilianGerhardt Thanks Maximilian. net however it creates a large code due to there being 8 charachters for each Led like this 0x000000, to make the code smaller I would like to express the led array values in this smaller format 0x00 which is generated using this converter File to hex In addition images stored in the LittleFS Flash filing system or "PROGMEM" arrays can be used with the RP2040, ESP8266 and ESP32 processors. In Arduino programming, PROGMEM stores data in the microcontroller's flash memory instead of RAM. - PROGMEM is not needed on the ESP32, not with internal or with external flash. This program converts various types of images into a byte array suitable for many applications, especially for showing them on display. How is that it DOES work to use PSTR() strings with “normal” functions, not the dedicated _P versions? Is it because ESP8266 is NOT harvard architecture, so in fact “normal” function can access the “flash” addresses? Then, I guess, F() macro is unnecessary on ESP chips, as normal functions can access data stored in FLASH with PSTR()? 10 PCB por 5$: https://www. Th PROGMEM is useful for Arduino Boards that have limited SRAM, but yet many Arduino users and even some library developers don't use it. braun@gmx. 37 MB) Jun 23, 2025 · Here is the simple method I used to setup ESP32 development board in VS Code with PlatformIO and run a basic LED Blink code. ESP32 WiFi Library Example Arduino IDE, WiFi Connection, Modes, Protocols, etc. Mar 31, 2018 · Espressif ESP32 Official ForumWho is online Users browsing this forum: Bing [Bot], Bytespider, Google [Bot], L_Stout, meta-externalagent, pmoreira, Qwantbot, trendictionbot and 2 guests May 30, 2017 · Does this CPU architecture allow to keep constant data in flash memory, similar to other Harvard CPU architectures (AVR for example) or is constant data always copied from flash to RAM on start-up? If flash based constant data access is possible, what is the proper declaration to do this? Is there a PROGMEM attribute or something similar which can be added to a declaration? Feb 12, 2023 · PROGMEM can save a little bit of memory on ESP8266, but not much really – less than 10% – it will not solve the issue of running out of RAM. c (1. PlatformIO [中文] What Is PlatformIO? Installation Configuration Tutorials Project Examples Next Steps What Is PlatformIO? PlatformIO is a cross-platform embedded development environment with out-of-the-box support for ESP-IDF. so the image is in a . Which is to be stored in the ESP progmem. Upvoting indicates when questions and answers are useful. Tried online tool and . Guide to PROGMEM on ESP8266 and Arduino IDE ¶ Intro ¶ PROGMEM is a Arduino AVR feature that has been ported to ESP8266 to ensure compatibility with existing Arduino libraries, as well as, saving RAM. All processors are configured in ConfigFS. That makes sense since, per ibernstone's link, PROGMEM is a no-op on ESP32. On the ESP32, there is no need for Progmem because constant data is automatically stored into Flash, and can be accessed from Flash without copying into RAM first May 22, 2023 · The PROGMEM variable modifier is a reserved keyword in Arduino. Dec 10, 2017 · PROGMEM adequately puts strings in flash. Contribute to espressif/arduino-esp32 development by creating an account on GitHub. I've been testing the Jun 14, 2021 · I have a ESP32 configured as webserver. Arduino框架下ESP32/8266使用PROGMEM功能将数据存储到flash中的使用规范，代码先锋网，一个为软件开发程序员提供代码片段和技术文章聚合的网站。 This Python script, minifies and converts HTML,CSS and Javascript files, to an char array of hex values. 0 (or later) in the Arduino IDE to avoid File definition conflicts if the SPIFFS and SD libraries are used together. How to really solve it? Jun 1, 2020 · How to do this so that variable data will be added to the webpage in real time? Keep in mind that I want to keep the HTML page on PROGMEM! Dec 26, 2017 · The objective of this ESP32 Arduino Tutorial is to explain how to serve a simple HTML page from the ESP32, using the Arduino core. pcbway. The problem is, now that I've got everything (apparently correctly) wired up, I have no idea what to do. write() function that accepts as arguments Jan 4, 2017 · Note that the architecture of the ESP32 chips is different from the Atmel ones in Arduino; the ESP32 uses an unified address space for both flash and RAM. and ot Oct 31, 2023 · ESP32のC言語、C++言語で、PROGMEMは変数の修飾子を使用すると、データをSRAMではなく、ROMエリア（フラッシュメモリ，プログラムメモリ）に配置できます。RAMの残り容量が不足する場合、ROMエリアに変数を移動させることを検討してください。 To save SRAM I want to use PROGMEM. When we speak about web server we know that the basic is serving a web page, in a micro-controller we have some solution to do that. UI graphics editor for embedded screens with pixel perfect code builder and export. Minify HTML, CSS and Javascript files to reduce the size. Contribute to vishnumaiea/ESP32-Snippets development by creating an account on GitHub. ESP32 integrates an antenna switch, RF balun, power amplifier, low-noise receive amplifier, filters, and power management modules. Arrays in the C++ programming language Arduino sketches are written in can be complicated, but using simple arrays is relatively straightforward. What is Arduino PROGMEM. Harvard architecture. Just declare something as 'const' and the compiler will make sure it won't be loaded into RAM. There is How to use PROGMEM with Arduino. This post show you how to save a data file such as an MP3 audio file into the RAM memory of an Arduino or ESP32 microcontroller. The variable data in the HTML page comes via a XMLHttpRequest call at the end of the loading of the page. GZIP Compression for HTML, CSS and Javascript files. I'll continue to try additional approaches. Dec 30, 2020 · You can use the send_P method with a static template in progmem that contains placeholders for your values, and a function that returns the values for your placeholders. I have multiple webpages, that I include as files for example index. naeenj dhrl oibb exj jwcg gjs lczli sifnyq gxfby pquptm hmh swev vwhgf jkrr seb