For a long time, ESP8266 is a popular Wi-Fi module, which has been widely used in many projects and products. ESP32 of Espressif is called a new and improved version of ESP8266. Should we upgrade ESP32? This article will introduce the features of these two products. All the technical information in the article can be obtained in the chip data sheet on the Espressif website. If you just want to know them quickly, please check the legend at the end of this article.

ESP8266 overview

Espressif's ESP8266EX chip is widely used in ESP8266 wifi module. It is a chip with a complete TCP/IP stack and single-chip functions. It has a built-in Tensilica L106 32-bit RISC processor (80MHz). The clock speed is 160mhz, and iBus, dBus and AHB interfaces are built in at the same time. Up to 16MB of external SPI flash memory can be used. ESP8266EX supports 14 wireless channels and 2.4GHz receiver and transmitter. In terms of Wi-Fi (72.2mbps), ESP8266EX implements TCP/IP and a complete 802.11 b/g/n WLAN MAC protocol (2 virtual Wi-Fi interfaces).

ESP8266EX chip is in Mode-sleep, Light-sleep, Deep-sleep three power management modes (the fourth is active mode), wireless and Wi-Fi will be disabled. The chip interface includes 17 GPIO pins, 4 software-implemented PWM output pins, and SDIO, SPI, HSPI, I2C, I2S, UART interfaces. The ESP8266EX chip also supports infrared remote control interfaces and embedded analog-to-digital converters.

ESP32 overview

ESP32 chip (including: ESP32-d0wd, ESP32-d0wdq6, ESP32-d2wd, ESP32-s0wd) integrates Wi-Fi and dual-mode Bluetooth. Depending on the model difference, ESP32 contains one or two low-power Xtensa 32-bit LX6 microprocessor(s) with a maximum clock speed of 240 MHz (usually 160 MHz) and Xtensa RAM/ROM, local memory and JTAG interface.

Unlike ESP8266EX, ESP32 has embedded flash memory of different sizes and supports multiple external QSPI flash memory and SRAM chips (up to 16MB). The wireless function of ESP32 is the same as ESP8266, but a balance and transceiver switch is added. Compared with the ESP8266EX chip, another improvement is that ESP32 embeds an RTC clock, which implements TCP/IP and a complete 802.11 b/g/n Wi-Fi MAC protocol (4 virtual Wi-Fi interfaces), and the data rate is up to 150mbps, supports the old Bluetooth protocol and Bluetooth low energy protocol, but these functions will be disabled in the five power management modes.

The ESP32 chip has 34 GPIO pins, and most GPIOs can be configured with internal pull-up or pull-down resistors, and can be multiplexed with SDIO, UART, etc. ESP32 also has two 8-bit DAC channels and a 12-bit SAR ADC, which supports measurements from 18 channels. In addition to the SDIO, SPI, HSPI, I2C, I2S and UART interfaces, the ESP32 chip also has Hall sensors, 10 capacitive sensing GPIOs and an Ethernet MAC interface.

Should it be upgraded?

In general, ESP32 is more powerful than ESP8266. In general, ESP32 has advantages in the following aspects:

1. 1. Power consumption: The working current of ESP32 is 5A and the power consumption is lower than ESP8266's 20A.

2. Clock speed: The clock speed of ESP32 is also twice faster than ESP8266.

3. 3. Interface expansion: ESP32 Bluetooth and GPIO have more pins, which can satisfy more connections.

The only drawback after the upgrade is software support. In terms of cost, although both are low-cost products, the cost of ESP32 is twice that of ESP8266. Therefore, if your project relies on software that is fully mature and no longer updated, ESP32 may not support it. If your existing equipment is working properly and you have no plans to add new features, then the upgrade is not worth it. Conversely, if your project requires ultra-low power consumption or needs more GPIO, or even more powerful processors and connectivity, then it is worthwhile to upgrade to ESP32.