ESP-01 ESP8266 Archives - CyberBlogSpot

ESP-01 and ESP-01S Pinout and Configuration

admin — Mon, 06 Feb 2023 19:59:12 +0000

Figure 1. ESP-01 ESP8266 Microcontroller Board Pinout

ESP-01 and its latest version ESP-01S are popular microcontrollers with Wi-Fi networking capabilities. They are part of the ESP8266 family of microcontrollers manufactured by Espressif Systems. In this article, we will learn the ESP-01 and ESP-01S pinout and configuration in actual applications.

ESP-01 Wi-Fi Module Specifications

Power Supply:
Voltage 3.0V ~ 3.6V
Current >300mA

Current Consumption:
Continuous Transmission: Average: ~ 71mA, Peak: 300mA
Modem Sleep: ~20mA
Light Sleep: ~2mA
Deep Sleep: ~0.02mA

SPI Flash Memory:
Default 8Mbit (1MB)

Interface:
UART/GPIO

IO Port:
2

UART Baud Rate:
Support 300 ~ 4608000 bps
Default 115200 bps

Frequency Range:
2412 ~ 2484MHz

Transmit Power:
802.11b: 16±2 dBm (@11Mbps)
802.11g: 14±2 dBm (@54Mbps)
802.11n: 13±2 dBm (@HT20, MCS7)

Receiving Sensitivity:
CCK, 1 Mbps : -90dBm
CCK, 11 Mbps: -85dBm
6 Mbps (1/2 BPSK): -88dBm
54 Mbps (3/4 64-QAM): -70dBm
HT20, MCS7 (65 Mbps, 72.2 Mbps): -67dBm

For a complete specifications, you may refer to the ESP-01 Product Specification PDF.

ESP-01 and ESP-01S Pinout

Have you just bought a new ESP-01 Wi-Fi module? Take a look at
How to Test an ESP-01 ESP8266 Module

Learn how to differentiate between ESP-01 and ESP-01S Wi-Fi modules, see:
Difference Between ESP-01 and ESP-01S

Figure 2. ESP-01 Module Pinout A

Figure 3. ESP-01 Module Pinout B

Figure 4. ESP-01 Module Pinout C

ESP-01 Pin Descriptions

TX – UART0 data send (transmit) pin, also known as GPIO1.
RX – UART0 data receive pin, also known as GPIO3.
CH_PD – Chip Power Down (also known as CH_EN or Chip Enable) – Chip enable pin, active high
RST – External reset pin, active low
GPIO2 – General Purpose Input / Output
GPIO0 – General Purpose Input / Output
VCC – +3.3 Volts Supply Positive
GND – Ground – Supply negative

ESP-01 Module Breadboarding and Adapters

When breadboarding, you can not insert the ESP-01 module as it is. A few years ago, you do all sort of tricks to breadboard an ESP-01 module, from bending the header pins to making your own DIY adapter. Luckily, now you can buy a cheap breadboard adapter for the ESP-01 module. See Figure 5.

Figure 5. Breadboard Adapter for ESP-01 Module

If you will be connecting the ESP-01 board to an Arduino board, you must remember two (2) things:

Do not supply the ESP-01 module with the 3.3V output from the Arduino board – the ESP-01 module, as per specification above, may require up to 300mA of current. The 3.3V regulator on the Arduino board may overheat and may become damaged.
Provide logic level translation between the ESP-01 and the Arduino board – the Arduino board uses 5V logic while the ESP-01 module uses 3.3V logic.

A good ESP-01 adapter that can satisfy the requirements for interfacing with Arduino boards is shown in Figure 6. It has a built-in 3.3V regulator and two (2) bi-directional logic level converters for the RX and TX pins. The schematic diagram for the adapter is shown in Figure 7.

Figure 6. ESP-01 Adapter with Voltage Regulator and Logic Translator

Figure 7. Schematic Diagram of ESP-01 Adapter

ESP-01 Programmers

ESP-01 USB-to-Serial Converter Programmer Module

Unlike the other ESP8266 boards, ESP-01 boards need a programmer to be uploaded with programs or sketches from the Arduino IDE. An inexpensive programmer is shown below in Figure 8. The programmer uses a Silabs 2104 serial to USB converter chip. With this programmer, you just plug it into your computer’s USB port, select the proper COM port and start uploading sketches.

Figure 8. ESP-01 Programmer or Flasher

DIY USB-to-Serial Converter Programmer

If you do not have a programmer module but you have an available USB-to-serial converter, you can wire it up as an ESP-01 programmer. The schematic diagram of a DIY programmer is shown in Figure 9. With this programmer, you need to put the ESP-01 module into programming mode before uploading a sketch. This is done by holding down the Flash switch, pressing and releasing the Reset switch, and then releasing the Flash switch.

Figure 9. DIY USB-to-Serial Converter Programmer

Shown below in Figures 10, 11, and 12 is my DIY ESP-01 programmer. The USB-to-serial converter connects to the programmer board via the 4-pin male header on the board.

Figure 10. My DIY ESP-01 Programmer

Figure 11. My DIY ESP-01 Programmer with an ESP-01 Module

Figure 12. USB-to-serial Converter

Arduino Board as ESP-01 Programmer
Another option for an ESP-01 programmer is to use an Arduino board. You may use any available Arduino board such as Arduino Uno, Arduino Nano, etc.

Figure 13. Schematic Diagram of Arduino Uno as ESP-01 Programmer

The idea here is to use the Arduino board’s built-in USB-to-serial converter. The schematic diagram in Figure 13 is the same as the DIY ESP-01 programmer in Figure 9, but the USB-to-serial converter was replaced with an Arduino Uno.

As previously discussed above, the 3.3V output from the Arduino board should not be used. Instead, a 3.3V voltage regulator was provided for the ESP-01 module. Also, a logic level converter was used consisting of a 2.2K resistor in series with a 3.3K resistor acting as a voltage divider. This protects the RX pin of the ESP-01 module from being exposed to a 5V signal from the Arduino board. Note that the TX pin of the ESP-01 module was connected directly to the TX pin of the Arduino board. We can do away with the logic level converter because the TX pin is acting as an output (outgoing signal).

You may have noticed that the TX and RX pins of the Arduino board are connected to the corresponding TX and RX pins of the ESP-01 module. But in the DIY programmer in Figure 9, the TX and RX terminals are cross-wired. That is, the TX pin of the USB-to-serial converter is connected to the RX pin of the ESP-01 module and ,vice versa, the RX pin of the USB-to-serial converter is connected to the TX pin of the ESP-01 module.

If you want to find out why the Arduino board’s RX and TX pins are wired straight thru and not crossed over with the ESP-01 board, consult an Arduino board schematic and look at how the MCU chip and the USB-to-serial converter chip are wired. I am leaving this one as an exercise for the reader.

References on ESP-01 and ESP-01S Pinout and Configuration

ESP-01 Specification
ESP-01 Datasheet

The post ESP-01 and ESP-01S Pinout and Configuration appeared first on CyberBlogSpot.

Difference Between ESP-01 and ESP-01S

admin — Sun, 05 Feb 2023 05:44:18 +0000

Figure 1. ESP-01/ESP-01S ESP8266 Wi-Fi Module Pinout

The ESP-01 Wi-Fi module is one of the most popular ESP8266-based microcontroller board. It is very inexpensive and widely available. If you are new with ESP-01 modules, or are contemplating on buying one, you are lucky for visiting this page. We have here all the necessary information on the difference between ESP-01 and ESP-01S Wi-Fi modules.

The ESP-01 module and the ESP-01S module are functionally the same. However, knowing the difference between the two is very important because it can affect how you wire them to external circuits. Also, the boards have different current consumption owing to their difference in the number of onboard LEDs.

ESP-01S is a Newer Version

First off, the ESP-01 module was the original version that was popularized almost a decade ago. The ESP-01S is the newer version. At the time of this writing, circa 2023, the original ESP-01 module is still widely available. Most online stores would allow you to choose between an ESP-01 or an ESP-01S. But some stores may sell you an ESP-01 for an ESP-01S, or vice versa.

Difference in Physical Appearance

At first glance, the two modules look the same. However, a close examination of the boards will show the difference in the number of LEDs (Light Emitting Diodes). Please see Figure 2 below. In the original ESP-01, there are two (2) small LEDs. On the other hand, the ESP-01S has a single, bigger LED.

The difference becomes more apparent when you supply power to the boards. The ESP-01 board will have a red LED light turned on indicating the presence of power. On the ESP-01S board, you will only see a blue LED flash for a while when the power is applied.

Figure 2. Physical Comparison of ESP-01 and ESP-01S Modules

The Blue LED Wiring Difference Between ESP-01 and ESP-01S

Although both boards have a blue serial-activity LED, the blue LEDs are wired differently. See Figure 3. In the ESP-01 board, the blue LED is connected on the VCC and the TX pins, while on the ESP-01S, it is connected on the VCC and the GPIO2 pins. On both boards, a 2.2K ohms resistor is used in series with the blue LED as a current limiter.

Figure 3. Internal Wiring Comparison of ESP-01 and ESP-01S Modules

Pull-up Resistors on ESP-01S

Another difference between ESP-01 and ESP-01S is the presence of three (3) pull-up resistors on the ESP-01S module. Pull-up resistors are used to provide a logic HIGH signal to a circuit. As shown on the right side of Figure 3 above, three (3) 12K-ohm resistors are connected from the VCC to the RESET, GPIO0, and CH_PD pins on the ESP-01S board.

Prior to the availability of the ESP-01S module, a popular ESP-01 wiring scheme for adding a reset switch and a programming switch is shown below in Figure 4. First of all, in order to power up the ESP-01 board, you need to pull up the CH_PD (Chip Enable/Power Down) pin. Next, you connect the RESET pin to the VCC because you do not want the RESET pin hanging and be vulnerable to noise causing unexpected resets. And third, pulling up the GPIO0 pin to VCC will automatically run the program or sketch loaded on the ESP-01 module after a power up or a reset.

Figure 4. Schematic Diagram of ESP-01 with Reset and Programming Switches

On the newer ESP-01S module, the circuit shown above will be a lot more simple. There is no need to externally supply the three (3) pull-up resistors. See Figure 5.

Figure 5. Schematic Diagram of ESP-01S with Reset and Programming Switches

Summary on Difference Between ESP-01 and ESP-01S

The ESP-01 and the ESP-01S Wi-Fi modules are functionally the same. The ESP-01S module is a newer version of the original ESP-01 module. The ESP-01 module has a red power indicator LED that is absent on the ESP-01S. Both modules have a blue LED that indicates serial activity. However, the blue LED is wired differently on each module’s version. And finally, the ESP-01S module has three (3) on board pull-up resistors that are missing on an ESP-01 module.

References on Difference Between ESP-01 and ESP-01S

ESP8266 on Wikipedia
ESP8266 Boot Process

The post Difference Between ESP-01 and ESP-01S appeared first on CyberBlogSpot.

How to Test an ESP-01 ESP8266 Module

admin — Wed, 01 Feb 2023 19:31:54 +0000

Figure 1. ESP-01 ESP8266 Module

When you buy a new ESP-01 ESP8266 module, the very first thing to do is to test it. That is, you need to make sure that you have a good and working ESP-01 module. We will take a look at the different methods of testing the ESP-01 ESP8266 Wi-Fi module.

Differences Between ESP-01 and ESP-01S ESP8266 Module

Before we proceed, be aware that there are two (2) versions of ESP-01 modules. The older ESP-01 module and the newer ESP-01S module. Both modules are functionally the same. However, there are two points worth mentioning here.

Figure 2. ESP-01 Module and ESP-01S Module Comparison

First, the ESP-01 has two (2) LEDs, a red LED power indicator and a blue LED that indicates serial activity. On the other hand, the newer ESP-01S has only one (1) LED, the blue LED light (see Figure 2 above). Moreover, the blue LED serial activity indicator light is wired differently on each module. That is, on an ESP-01 module, it is connected on the TX pin (GPIO1) while on the ESP-01S module, it is connected on the GPIO2 pin. And as a side note, pins GPIO0 and GPIO1 are both serial TX capable pins (refer to the ESP-01S schematic diagram at the end of this article).

Second, the ESP-01S module has three (3) additional on-board resistors used as pull-up resistors. These pull-up resistors are 12K-ohm resistors each connected on the GPIO0, the RESET, and the CH_PD pins. You may also want to refer again to the ESP-01S schematic diagram included at the end of this article.

Quick and Dirty Test

The ESP-01 module is shipped with a program called AT firmware. The firmware will let you send AT commands to configure and program the module. More important, the module is configured as a Wi-Fi Access Point (AP) when shipped. Therefore, a quick and dirty test is to power the ESP-01 module and use a smartphone to connect to the Access Point.

Power up the ESP-01 module as shown in Figure 3. Notice that we need to connect the ESP-01 module to a 3.3V power supply. Do not connect the ESP-01 module to the 3.3V output of an Arduino board. Provide a separate 3.3V power supply with sufficient current capacity. Also, note that a 10K ohms resistor is connected from the CH_PD pin to the VCC or the 3.3V supply. The CH_PD (Chip Power Down / Enable Pin) pin has to be pulled up to the VCC for the module to function. If you have the ESP-01S module, you do not need to connect a 10K ohm resistor on the CH_PD pin. As per discussion above on the differences between the ESP-01 and the ESP-01S modules, the ESP-01S already has a 12K-ohm pull-up resistor on the CH_PD pin.

Figure 3. ESP-01 8266 Module with Power Supply

After powering up, you should see the ESP-01 access point when you scan for Wi-Fi devices. The default SSID of the ESP-01 module I am using is ESP_7B0F95. See Figure 4.

Figure 4. Smartphone Wi-Fi Scan

Connect to the ESP-01 Access Point.

Figure 5. Smartphone Wi-Fi Connected to ESP-01 Access Point

Click on the Settings icon (gear icon) and see the network details of the ESP-01 module Access Point.

Figure 6. The ESP-01 Access Point Network Properties

AT Command Test

For the next test, you need an ESP-01 programmer or flasher. An inexpensive programmer/flasher is shown below in Figures 7. In Figure 8, the ESP-01 module is shown inserted into the programmer/flasher. If you do not have a programmer/flasher, it is possible to use an Arduino board as a programmer/flasher. Also, if you have a USB-to-serial(TTL) converter, you could wire it up as an ESP-01 programmer/flasher.

Figure 7. An ESP-01 Programmer/Flasher

Figure 8. ESP-01 Module on a Programmer/Flasher

Insert the ESP-01 module to the programmer as shown in Figure 8 and plug the programmer to the computer. If it is your first time to use your programmer/flasher, you may have to install its device driver. Open the Arduino IDE and set the appropriate COM port for your programmer (Figure 9). For the meantime, there is no need to set the Board type.

Figure 9. The Arduino IDE Showing How to Select COM port

Open the Serial Monitor and change the settings as shown in Figure 10. The line ending setting must be set to both newline and carriage return, “Both NL & CR”. Additionally, the baud rate setting must be set to “115200 baud”.

Figure 10. The Arduino IDE Serial Monitor Settings

Now type “AT”, press the return key and the ESP-01 module should reply “OK”.

To view the ESP-01 module firmware version, type “AT+GMR”.

Type “AT+CIFSR” to view the Access Point’s IP address and network MAC address. See Figure 11 for the output display.

Figure 11. The Arduino IDE Serial Monitor Showing the Results of AT Commands

For a complete guide on the ESP-01 module AT commands, see ESP8266 – AT Command Reference.

Programming with Arduino IDE

In the next test, we will upload a modified version of the sample sketch Blink from the Arduino IDE. The sketch should make the blue LED on the ESP-01 module turn on and off.

IMPORTANT
Uploading an Arduino sketch to the ESP-01 module will erase the AT firmware. The AT commands will not work anymore after the upload. If you want to be able to restore the original firmware, please see the article
How to Save and Restore ESP8266 and ESP32 Firmware.

With the ESP-01 module still in the programmer/flasher, open the Arduino IDE and change the Board setting to “Generic ESP8266 Module” as shown in Figure 12.

Figure 12. The Arduino IDE Showing How to Set the MCU Board

Create a new sketch, copy and paste the blink program shown below. Upload the sketch to the ESP-01 module. The blue LED should start blinking after successfully uploading the sketch.

/*
 * cyberblogspot.com 01Feb2023
 */

#define LED_BUILTIN 1                // GPIO1 for ESP-01, GPIO2 for ESP-01S
                                     // Change to 2 for ESP-01S module
void setup() {
  pinMode(LED_BUILTIN, OUTPUT);   
}

void loop() {
  digitalWrite(LED_BUILTIN, LOW);   // Turn the LED on (ESP-01 LED is active low)
  delay(1000);                      
  digitalWrite(LED_BUILTIN, HIGH);  // Turn the LED off 
  delay(1000);                     
}

Schematic Diagram of ESP-01S ESP8266 Wi-Fi Module

Figure 13. ESP-01S Wi-Fi Module Schematic Diagram

References on How to Test an ESP-01 ESP8266 Module

ESP8266 on Wikipedia

The post How to Test an ESP-01 ESP8266 Module appeared first on CyberBlogSpot.