Hi, Hellweaver. Thank you for your quick reply. What a pity you don’t like the colorful design.
For your question, as long as the signal pin sequence is the same, IIC port on the board will be compatible with the Adafruit Stemma/Sparkfun qwiic module. However, even you could plug it in Grove interface, these two interfaces are not the exactly the same on their shape, we do not recommend to do so for avoiding unexpectable damage of the connector.
P.S.: Grove - Qwiic Hub could allow you to either use Qwiic/STEMMA QT modules on Grove controller or use Grove modules on Qwiic/STEMMA QT controller. Please refer to:
The card slot is designed for expanding memory, so yes you could put circuit python code on it as well as other libraries you need, which makes more possibilities for Seeeduino XIAO.
We currently released a Seeed Ranger Program. Seeed Ranger could apply for free Seeed Products for project use from time to time. Should you be interested in this program, please visit:
I am not a big fan of the special designs. It may appeal for a limited batch, but since the expansion board is touted as “premier” or “professional”, black is better.
I have mixed feelings about the new design. It tries to merge the two scenarios I’ve mentioned earlier, a Development expansion board and an Expansion board.
1. Development expansion board
I strongly recommend using a SWD connector instead of the 0.1" pins of the last iteration. The SWD connector is fool-proof and standard debuggers like the Segger Edu mini comes with the right cable to plug and play.
As an expansion board, the last iteration lacks a second I²C Grove connector. As I²C is very popular for connecting Grove sensors and devices, I would expect a second I²C connector. I would prefer design A or design II or III.
Other comments
Doesn’t the SAMD21 MCU already include an RTC? So we could get rid of the additional RTC IC.
I would prefer a battery holder to another connector for the RTC battery (as in design A).
Do all designs include an SPI Flash memory, required for Python?
Conclusion
I am not sure about the screen. So I would go for design III with a screen or design C without. Both bring a large number of Grove connectors within a constrained size, and could answer the two scenarios I’ve exposed earlier.
Seeed Ranger Program
I’ve applied to the Seeed Ranger Program and I’m awaiting the answer.
Choosing the hardware wasn’t easy as I’ve already ordered most of it, including boards and peripherals.
I like the classical type, but if I hada to make a choice, I’d choose either the “chocolate” or the lower right pink version. I love the OLED display, my Xiao for Grove doesn’t have it!
The reason why there are fewer Grove connectors in the latest version is that we are trying to avoid confusion caused by the reuse of GPIOs.
SeeeduinoXIAO has led out 14 GPIOs including 3.3V/5V and GND. Other 11 GPIOs will be used as:
The add-on SD card would be able to expand memory for Python and the library, just as the same function of SPI-flash and larger memory space.
SAMD21 MCU already include an RTC but Seeeduino XIAO did not lead out the required pin for it, so it may be more practical to just add another RTC chip on board.
For the more number of Grove IIC you are expected, we didn’t put two of it only because of the space concern, and Grove IIC Hub would be able to fix the problem if more IIC devices are needed, so we keep only one on board.
Glad to hear that. My suggestion is that you could have a look at our newest released products to see what new projects you could build. No need to force yourself to apply anything you do not really need or you already have. Our review will be flexible to some extend, so just illustrate what you are going to build, components you are going to use, indicate what you already have so you do not need to apply for it. If your project is selected, we may also offer a coupon for your future purchase. Looking forward to your project:)
Don’t worry, we will take all users’ inputs into serious consideration. And that’s why we put the design here to ask for more opinions.
Though I spend some time on the design of new style silk print, so far it seems classical type is more popular in the forum.
Glad to know that you like the OLED.
I found that too many Grove is not friendly enough as it will cause confusions for users when many GPIOs being reused. For this reason, I have to some extend abandoned the previous design that have eight Groves.
According to your last reply, I modify the design as folow. May also have a look:
SPI Flash is replaced by SD card since it will have the same function, and SD card could be removed and it is more convenient to copy things somewhere else using card reader.
I did not draw RTC chip on board but will find the appropriate space to allocate it.
I’m very Glad to see you take the time to ASK.
as an aside, You DO NOT always include the pins for the Xiao’s etc.
Why not switch to a Socket on the Board.or here When a person orders a chip and dev board and when they recieve it. ONE must solder to even get up and going. I see this as a barrier to entry for many new people wanting to try your Xiao chips. Imagine the " 3rd Grader’s " the ability to open the product and place it in and program it WOW and Your on the Path of learning WAY faster than anything from Adafruit, DF-robot, Hak5 ?, Sparkfun is the closest IMO.
Lastly IS it really the " Premier " well it would be if it checked all the boxes.
Hope that Helps
Happy Holidays & Merry Christmas
solder to even get up and going. I see this as a barrier 
to entry for many new people wanting to try your Xiao chips. 
Imagine the " 3rd Grader’s " the ability to open the product and place it in and program it WOW and Your on the Path of learning WAY faster than anything from Adafruit, DF-robot, Hak5 ?, Sparkfun is the closest IMO.
Lastly IS it really the " Premier " well it would be if it 
checked all the boxes.
