Tag Archives: esp

ESP8266 (NodeMCU) ADC analog value on dial gauge

This is advance tutorial it uses knowledge for JavaScripts, ESP8266, CSS and HTML. In this example we are reading analog value of ADC and display it on HTML web page, which is served by ESP8266 or NodeMCU web server, To get more details on basic HTML page creation in ESP8266 read this.

Continue reading ESP8266 (NodeMCU) ADC analog value on dial gauge

Example of ESP8266 Flash File System (SPIFFS)

This tutorial explains in depth ESP8266 Flash File System Called as (SPIFFS). There are two ways to store data on ESP8266 one is using internal EEPROM which is of 512 Bytes but you can write data 1 millions of times (no file system). and Second is use of SPI Flash (64kBytes to 3Mbyte), when you see ESP-01 a small 8-Pin Chip is present near to the ESP8266 which is FLASH memory connected to ESP through SPI. In this flash memory ESP stores the program. Along with program you can store your files on it. Limitation of this memory is it has only 10000 (ten thousand) write cycles.

Even though file system is stored on the same flash chip as the program, programming new sketch will not modify file system contents. This allows to use file system to store sketch data, configuration files, or content for Web server. Continue reading Example of ESP8266 Flash File System (SPIFFS)

How to get MAC and IP address of devices connected to ESP8266 ?

This post explains getting MAC address and IP address of devices connected to ESP8266. Typically, the MAC address is only visible on each end of a “hop” in a packet so if you are going from some device via WiFi through the router to some other device, the MAC address you would see would be from your device and the router. The router will typically have a table of IP addresses and associated MAC addresses for those devices that it has handed out an IP address to via DHCP. Continue reading How to get MAC and IP address of devices connected to ESP8266 ?


ESP8266 have 10 GPIO pins and 1 Analog Input. Pin numbers in Arduino correspond directly to the ESP8266 GPIO pin numbers. pinMode, digitalRead, and digitalWrite functions work as usual, so to read GPIO2, call digitalRead(2).

Digital IO (GPIO)

Digital pins 0—15 can be INPUT, OUTPUT, or INPUT_PULLUP. Pin 16 can be INPUT, OUTPUT or INPUT_PULLDOWN_16. At startup, pins are configured as INPUT. Continue reading ESP8266 GPIO PINS

ESP8266 mDNS

This tutorial explains how to Multicast DNS using ESP8266? In networking world it is difficult to remember ip address of each website and computer, to solve this problem Domain Name System (DNS) is used to make human understandable names. In ESP8266 when using ESP as web server, It is difficult to remember ip address of ESP8266 and also it is difficult to identify ip address of ESP in DHCP mode. i.e. WiFi router assigns IP address to ESP8266. Most ESP8266 application doesn’t have display interface and they are not easy to access to know its IP address. To overcome this problem mDNS is used. Continue reading ESP8266 mDNS