The document details JTAG debugging with the ESP32, providing an overview of the hardware, including the ESP32 devkit and associated JTAG debugger. It includes instructions for connecting the ESP-PROG debugger, using Arduino IDE, Visual Micro, and PlatformIO for debugging applications. The author, Pete Gallagher, outlines key features, specifications, and links to resources for further exploration.

1. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
JTAG Debugging
with the ESP32
PETE GALLAGHER
PJGCREATIONS.CO.UK
22/06/2020

2. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
About Me
Pete Gallagher
@pete_codes / @PJGCreations
www.PeteCodes.co.uk
www.PJGCreations.co.uk
Pete@PJGCreations.co.uk
IT Consultant, Microsoft Azure MVP, Pluralsight Author,
Decades of Desktop, Web & Embedded Software experience,
Meetup Organiser,
STEM Ambassador, Code Club Organiser … Gadget Addict
Father of two inquisitive girls

3. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
What we’re going to be doing…
 The ESP32
 JTAG Hardware Debuggers
 Connecting the Espressif ESP-PROG
JTAG Debugger
 A Simple ESP32 App using Arduino IDE
 VisualMicro for VS2019
 PlatformIO for VS Code
 Debugging a Simple ESP32 App
 Q&A

4. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
The ESP32 DevKit

5. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
The ESP32 DevKit - Blocks
WiFi + BLE
ESP-WROOM-32
Microcontroller
Micro USB +
Virtual Serial Port
Built in LED
GPIO

6. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
The ESP32 DevKit - Specs
 Cheap - £7ish
 Dual Core ESP32 WROOM32 Microcontroller
 Clocked up to 240MHz
 4MB Flash (Program Memory)
 512K RAM
 RTC + 8K RAM
 512 Byte EEPROM
 2.4GHz Wifi
 Bluetooth and BLE
 GPIO inc SPI, UART, I2C, PWM, DAC Etc

7. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
The ESP32 Kit - Pinout
Enable
GPIO36
GPIO39
GPIO34
GPIO35
GPIO32
GPIO33
GPIO25
GPIO26
GPIO27
GPIO14
GPIO12
GPIO13
GND
VIN
GPIO23
GPIO22
GPIO1
GPIO3
GPIO21
GPIO19
GPIO18
GPIO5
GPIO17
GPIO16
GPIO4
GPIO2
GPIO15
GND
3v3
UART1 TX
UART1 RX
UART 2 TX
UART2 TX
SPI1 MOSI
I2C SCL
I2C SDA
SPI1 MISO
SPI1 CLK
SPI1 CS0
SPI2 MOSI
SPI2 MISO
SPI2 CLK
ADC 1+2

8. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
The JTAG Debugger

9. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
The JTAG Debugger
 Joint Test Action Group
 Direct Access to System Address and Data Bus
 Can read and write variable values
 Set break points and step through code
 Uses Serial Communication
 Connects to the Test Access Port (TAP)
 USB Connection to PC
 Uses OpenOCD to control
 Dupont connection to ESP32 DevKit
https://www.xjtag.com/about-jtag/jtag-a-technical-overview/

10. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
Connecting the JTAG Debugger
GND
TDI
TDO
TCK
TMS
3v3

11. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
Connecting the JTAG Debugger
TCK
TDI
TMS
TDO
GND
3V3

12. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
A Simple App

13. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
Visual Micro

14. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
Visual Micro
 Serial debugging
 Hardware debugging
 Supports hundreds of boards
 VS2017/2019 Extension
 Set breakpoints
 View variable values
 Free
https://www.visualmicro.com

15. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
PlatformIO

16. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
PlatformIO
 Hardware debugging
 Supports hundreds of boards
 Visual Studio Code Extension
 Set breakpoints
 View variable values
 Free
https://www.platformio.org

17. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
Links
 Arduino IDE
https://www.arduino.cc/en/main/software
 ESP32 DevKit
https://www.amazon.co.uk/SeeKool-Development-Microcontroller-Integrated-
Compatible/dp/B07DPP3BGZ/
 Espressif ESP-PROG
https://www.digikey.co.uk/product-detail/en/espressif-systems/ESP-PROG/1965-ESP-
PROG-ND/10259352
 Visual Micro
https://www.visualmicro.com/
 PlatformIO
https://platformio.org/
 JTAG Information
https://www.xjtag.com/about-jtag/jtag-a-technical-overview/

18. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
 Twitter
@pete_codes / @PJGCreations
 Email:
pete@pjgcreations.co.uk
 Website:
https://www.petecodes.co.uk
https://www.pjgcreations.co.uk
 Notts IoT:
https://www.nottsiot.co.uk
 Dot Net Notts:
https://www.dotnetnotts.co
 Notts Dev Workshop:
https://www.nottsdevworkshop.co.uk
 LATi:
https://www.lati.org.uk
 Agile Engineering Podcast:
https://agileengineeringpodcast.com/
Contact Me
Slides:
http://bit.ly/pjgesp32jtagtwitch

19. JTAG Debugging with the ESP32 – Copyright Pete Gallagher 2020 – @Pete_Codes
Questions?
Pete Gallagher
@pete_codes / @PJGCreations
www.PeteCodes.co.uk
www.PJGCreations.co.uk
Pete@PJGCreations.co.uk