I’m pleased to say, that M5Stack did it again. They managed to release another ESP32 based product and keep me on my tosies! From incredible small Atom (review pending), through most feature-packed M5StickC (review) to power development Fire Kit Core (review) – each product brought joy to my eyes despite being basically the same: an ESP32 based all-in-one development board. And they did it again thanks to M5Paper – a unique mashup between ESP32 and e-ink displays.
M5Paper – phone-size wonder
It’s not the first ESP32 & e-ink display combo, but it’s the first one I really wanted to have. Convincing M5Stack to send me one wasn’t the problem. The device is so high in demand, that I had to wait till Xmas to get mine. It is not just me that likes the concept. M5Paper is in stock right now, but if you are unlucky, it also surfaces on Banggood and AliExpress.
M5Paper nails the design thanks to 4.7-inch, 940*540 multitouch 16 level grayscale e-ink display. It’s not just an e-ink ESP32 module, it’s a well-thought-through product that deserves everyone’s attention. The phone form factor feels great in my hand and lightning-fast (for an e-ink) display creates this PDA alike impression. If you prefer a less expensive option and you don’t need the touchscreen for your project, you can always settle for an M5Stack Core Ink (review) instead.
While the device doesn’t make it difficult to peak inside, M5Paper isn’t designed to be opened and tinkered with. You won’t find any hidden pins or ways to interact with the board, but there is enough space to swap the LiPo battery for a bigger one, in case 1150mAh isn’t enough. And you get 3 Grove connectors to plug external sensors and other fun add-ons.
Under the hood, M5Paper comes with a very familiar ESP32 module surrounded by pretty decent hardware – just take a look at the specs:
|SP32-D0WDQ6-V3||240MHz dual core, 600 DMIPS, 520KB SRAM, Wi-Fi, dual mode Bluetooth|
|Ports||TypeC*1, HY2.0-4P*3 , TF-card(microSD) slot|
|E-Ink Display||Model Number：EPD_ED047TC1 | firstname.lastname@example.org″ | Grayscale : 16 Levels | Display area : 58.32*103.68mm | Display Driver : IT8951|
|Physical Button||Multi-function button*1 ， Reset Button*1|
It’s a very clever design to include BM8563 Real-Time Clock, as you can save a lot of power by using RTC to trigger the events rather than sleep policies of ESP32. Combined with the e-ink, M5Paper can last ages on a single charge. This is reinforced by the default firmware as well. The power button at the back of the device disables ESP32 when pressed and the “volume” rocker wakes it up when held for a couple of seconds.
Putting “kindle” into M5Paper
The device feels like a small-sized phone in the hand. It has just enough screen estate to break the development board impression and appear as intriguing “kindle” alike device. It’s not an e-reader, M5Paper is even more awesome. The display is simply perfect as far as e-inks go. 16 level greyscale enables images and advanced shading while multitouch (2-point) touchscreen is responsive enough, so I don’t hate using the onscreen keyboard.
Navigating through menus is fairly quick, and even though menus take 2-3 screen refresh cycles to fully materialise, you can quickly jump from screen to screen. Frankly speaking, I played with less responsive LCD screens in the past!
Just remember, there is no backlight. The device is perfectly visible in a full sunshine, but completely useless in the dark.
The “I’m still all-in-one development board”
It’s not the first take on e-ink display by M5Stack. They merged it before with their Core INK – an e-ink-equipped take on M5Stick series. Unlike Core INK, M5Paper is missing one thing that I really liked – the ability to program the board in the web browser wirelessly. I can only hope that the support will be added soon, as programming M5Stack wirelessly feels like magic.
Update: 23/01/2021: Dev team from M5Stack had confirmed that integration for UIFlow is on the way, we should see M5Paper joining the UIFlow as well soon!
Update: 09/02/2021: UIFlow is now available – read more about the process here
Just like other M5Stack devices, M5Paper supports Arduino IDE & MicroPython. The product is fairly new, so it lacks in community projects, but the documentation explains basics and shows you how to handle an e-ink display with sample projects. Apart from online examples, M5Paper supports M5Stack Burner software. You can try community projects and easily reverse back to the default firmware.
Unless an e-ink is what you really want, I’d pick Core INK series if you are getting started. M5Paper expects customers a bit of knowledge to take the advantage of the ESP32 inside. The demo panel promises interesting features, but to my disappointment, the “Home Automation” panel isn’t released as a source code, and I cannot integrate it with my house appliances. It’s a shame.
I’m a little disappointed that M5Paper isn’t compatible with UIFlow, I hope this will change with time. I do love the device and I’m already thinking about potential projects. If you feel comfortable with Arduino IDE programming, go for it. Hardware-wise, M5Paper is an amazing device worth the money spent on it. But if you are getting started, expect a steeper learning curve, limited tutorial materials, perhaps, you would be better off with M5Stack Core 2 or Core INK instead. I will try to get my hands on both! If you have any questions, please let me know in this Reddit thread.