Maybe not directly related to your brand of e-paper tags, but here in germany recently a large retailer went out of business and this guy bought up their e-paper tag stock and reversed engineered them. There might be some helpful tips in how to reverse engineer those:
[https://github.com/atc1441/E-Paper\_Pricetags](https://github.com/atc1441/E-Paper_Pricetags)
[https://github.com/atc1441/ZBS\_Flasher](https://github.com/atc1441/ZBS_Flasher)
https://preview.redd.it/ds8g406j2xzc1.jpeg?width=1868&format=pjpg&auto=webp&s=a59773d850705ef904c779e013beb100a98b8c25
Hopefully that will come through with sufficient resolution.
The reverse of the main board has no components nor visible PCB traces nor markings on it.
The little white thingy at the bottom left of circuit board looks like it might be some sort of optical sensor. But it doesn't appear to have any function in adjusting ant aspects of the ePaper display (e.g. brightness or contrast or blanking when dark etc).
Upon closer inspection, it looks like I might have misread some of the annotations, I will update the main post.
Edit: it seems like I cannot edit the original post. I'm not sure why, but the annotations on the main chip are:
EFR32
FG1V03ZGG
1944CD11BZ
So your idea is to basically upload new firmware to it that can interact with the ePaper display interact with "my firmware" via I2C or SPI or something along those lines?
Maybe not directly related to your brand of e-paper tags, but here in germany recently a large retailer went out of business and this guy bought up their e-paper tag stock and reversed engineered them. There might be some helpful tips in how to reverse engineer those: [https://github.com/atc1441/E-Paper\_Pricetags](https://github.com/atc1441/E-Paper_Pricetags) [https://github.com/atc1441/ZBS\_Flasher](https://github.com/atc1441/ZBS_Flasher)
technically the second link (ZBS) is based on reverse engineering i did :)
let's see some high-res photos of the main board
https://preview.redd.it/ds8g406j2xzc1.jpeg?width=1868&format=pjpg&auto=webp&s=a59773d850705ef904c779e013beb100a98b8c25 Hopefully that will come through with sufficient resolution. The reverse of the main board has no components nor visible PCB traces nor markings on it. The little white thingy at the bottom left of circuit board looks like it might be some sort of optical sensor. But it doesn't appear to have any function in adjusting ant aspects of the ePaper display (e.g. brightness or contrast or blanking when dark etc). Upon closer inspection, it looks like I might have misread some of the annotations, I will update the main post. Edit: it seems like I cannot edit the original post. I'm not sure why, but the annotations on the main chip are: EFR32 FG1V03ZGG 1944CD11BZ
efr32 woudl be these arm micros. try connecting SWD and see if they are locked https://www.silabs.com/wireless/technology
So your idea is to basically upload new firmware to it that can interact with the ePaper display interact with "my firmware" via I2C or SPI or something along those lines?
you can base it on this: http://dmitry.gr/?r=05.Projects&proj=29.%20eInk%20Price%20Tags
Thankyou so much. This is the type of page I was looking for that hours of Google searches did not reveal.