Espressif ESP-Module-Prog-1 - Comfortably Program ESP32 Modules Without Soldering
Espressif's wireless microcontrollers are commonly provided in a modular format, which includes a PCB antenna. With the ESP-Module-Prog-1, they can be programmed when they are not soldered to the host PCB.
ESP32 modules are tremendously comfortable to use. Thanks to the integrated PCB antenna, no vector network analyzer is needed for antenna matching. Furthermore, the certification of the finished consumer electronics product is simplified by the use of a pre-certified wireless transmitter.
However, programming them - so far - required the design of a custom board such as the one documented at https://www.youtube.com/watch?v=Vjc5aMzY2P8. With the ESP-Module-Prog-1, Espressif now offers a different solution for programming ESP32 modules.
Spring Pins for Direct Attachment
Espressif offers two versions of the board, sold under SKUs ESP-Module-Prog-1 and ESP-Module-Prog-1R. From a technical point of view, they are similar - the figure below shows that the field of spring pins dominates one end. These mate with the module's rim connectors, providing a reliable connection for laboratory and benchtop use.
In addition, the presence of a USB-to-UART bridge and a USB-C port ensures the workstation can connect to the evaluation board. Code, whether written in IDF or Arduino, can then be deployed just as if the module were soldered onto the application PCB.
Inserting the module into the development board is easy if the following instructions, provided in the data sheet found at https://docs.espressif.com/projects/esp-dev-kits/en/latest/other/esp-dev-kits-en-master-other.pdf, are observed:
Mount the module to ESP-Module-Prog-1(R) as follows:
1. Place the module lightly on ESP-Module-Prog-1(R), making sure the castellated holes on the module are aligned with the spring pins on the board.
2. Press the module inward until you hear a \"click\", which indicates that the module has been successfully mounted.
3. Check if all the spring pins are clicked into the castellated holes. If there is a misalignment, you can use tweezers to poke the spring pins into the castellated holes.
As of this writing, Espressif provides two versions: one with pins on two sides, and the other with pins on all three sides. Espressif accommodates this by providing the above-mentioned SKUs. SKU one is more widely supported and offers compatibility with the following ESP32 modules:
• ESP32-WROOM-32
• ESP32-WROOM-32D
• ESP32-WROOM-32U
• ESP32-SOLO-1
• ESP32-WROOM-32E
• ESP32-WROOM-32UE
• ESP32-S2-SOLO-U
• ESP32-S2-SOLO-2
• ESP32-S2-SOLO-2U
• ESP32-S3-WROOM-1U
• ESP32-S3-WROOM-2
• ESP32-C6-WROOM-1U
Version number two is compatible with the following candidates:
• ESP32-WROVER-B
• ESP32-WROVER-IB
• ESP32-WROVER-E
• ESP32-WROVER-IE
Legacy Support via Special Adapters
The tool is not limited to supporting ESP32 modules - it can also mate with modules from the ESP8684 families. For this, the ESP-Module-Prog-SUB-01&04 and ESP-Module-Prog-SUB-02 are to be used. They are sub-boards that plug on top of the basic unit and appear as shown in the figure below.
Conclusion
If an ESP32 module needs to be programmed or checked before installation on a PCB, this can be done easily. This is helpful because it enables PCB assembly houses to perform final tests without access to the application firmware. In short, a product that is helpful in the entire ESP32 value chain.