I'm wondering if anyone has used the jaycar XC4421? As I'm looking at getting one. It has built in esp8266 and mega 2560 chips using a pair of dipswitches I can configure the serial ports between them and the computer. It would be greatly appreciated if you could please help.
Hi, @baltaridley
You need to post some basic info like this;
https://www.jaycar.com.au/duinotech-mega-2560-r3-main-board-with-wi-fi/p/XC4421?srsltid=AfmBOorTrTMWwwJ1V3h7z_bWfzOToY3E_UXoXr6Kn5RQ8K6f8FvxUI8G
Overview
Duinotech MEGA r3 development board with an integrated ESP8266 is an Arduino®-Compatible board which makes it easy to connect your projects to the cloud without the need for additional shields. Features the ATMega2560 and standard MEGA layout, and includes a set of DIP switches to configure the serial connections. It boasts more IO pins, more memory, more PWM outputs, more analog inputs and more serial ports than the UNO board. When you have a project that just needs more inputs, outputs and memory than the Duinotech Classic (UNO) can deliver, the MEGA has them in spades. And with 8 times the program memory, you have the room to write much larger programs to take full advantage of the increased IO. Despite its elongated size, standard shields will still drop straight onto this board.
The co-ax connector by the DC Power jack can be used to run an external antenna.
Uses a Micro-B USB lead such as WC7723 for connecting to the computer and uploading sketches. You can read more about it in the manual.
Please note:
• To talk to board you need to download and install CH340 Driver (search for driver on the net).
• You must upload code to both processors then configure the switches for them to talk to each other.
Tom.... 
You can do a search; questions about similar boards have been posted in the past.
I will keep that in mind.
Well I've gone through them all and they only have people who had minor questions or issues.
Maybe you should try to explain what you want to achieve or which problems you are encountering. Except for the fact that you want to know if anybody has used that board, there is no question in in your opening post.
And I have not used one so can't help further.
Well I'm trying to see if it's worth getting one as I have a seperat mega and esp32 wrover but don't have the level converters for serial whereas that's all built into the board that I saw at jaycar.
Depends what you want to do.
The ESP8266 is now obsolete and replaced with the ESP32 family.
The world is moving to 3.3volt processors and sensors, which makes a Mega soon obsolete too.
What are you doing what your ESP32 Vroom on it's own can't do.
The Vroom has a more powerful processor than the Mega.
The only advantage of that board is the many 5volt I/O pins.
But only if you need them.
Leo..
OK I will see about getting the mega variant.
I have bought some logic level converters should I just use those to interface the 2?
Question is why you want to kludge two processors together.
What is your project.
Leo..
I'm making a control panel that would be able to to controle things like lights small fans etc. But I also want to connect it to arduino iot cloud.
XC4421 is not a very good choice for use with Arduino Cloud IoT.
There are two common ways the ESP8266 is used by the Arduino community:
- As a Wi-Fi adapter module controlled by a standard Arduino board (e.g., Uno, Mega) over a serial connection using AT commands. In this usage, you will be writing Arduino sketches for and uploading to the standard Arduino board, not the ESP8266.
- As a standalone Arduino board. In this usage, you will be writing Arduino sketches for and uploading directly to the ESP8266.
The ESP8266 microcontroller on the XC4421 is intended for the first type of usage. Conversely, Arduino Cloud IoT can only be used with the second type of usage.
It is true that the XC4421can be used in the second type of usage. However, this will make things very complex because you would need to write sketch programs for each of the microcontrollers on the board, and implement a communication protocol between the two. Things will be much easier if you buy a board that doesn't require this dual microcontroller programming approach.
I suggest taking a look at these two boards:
Or if you really need more pins than those boards provide, the GIGA R1 WiFi is a good choice.
A control panel can be done in software, sent to a smartphone. Or with two I2C pins or SPI. WiFi doesn't need any pins. Only fans need physical pins and an ESP Vroom has plenty of them.
Your post doesn't explain why you need the many pins of a Mega.
Leo..
OK I will probably get the giga seeing as I have an 0v7670
I uhh have a few displays 7 segment and an lcd and a 4x4 keypad connected.
A bunch of I2C or SPI driven 7-seg displays and eight pins for the keypad are still within the pin limitations of a big-board Vroom ESP32.
Leo..
I'm using 74hc595 shift registers for thee 7 segment displays, and a 16x2 lcd in 4 bit mode and I need 4 pins for digit selection pins on the 7 segment display.
One of my clock displays with a 768-LED matrix is controlled with three pins of my ESP32-C3.
If you buy displays with parallel interfaces, then you pay more later, needing a processor with more pins. Your LCD display could have an I2C backpack on the back, needing only two I2C MCU pins that can be shared with other devices.
The board that you are referring to is an outdated non-standard Arduino board.
Good luck with support of that.
Leo..