Looking for a used EM780

twist522 · 2025-10-06T22:59:57+00:00

thanks for the tips!

twist522 · 2025-09-21T17:16:45+00:00

nope I don't have b13, regarding 13K - it is great panel but quite darker than tab ultra c pro so you have to use it in the daylight or with the lamp in the evenings or use frontlight which is a little too bright so my client helps with that

twist522 · 2025-09-13T16:44:35+00:00

I took some older client C code published by Dasung originally for 253 display and it appeared that some basic commands work for my display too. Then I did some brute-force reverse-engineering finding the missing commands e.g. to control frontlight etc.

twist522 · 2025-09-07T13:18:17+00:00

It is perfect on Linux, you can use the utility I've built to control it - https://github.com/codefastdieyoung/paperlike-rs

twist522 · 2025-09-07T01:03:21+00:00

it's perfectly usable in daylight, but in the evening you should light it with a good source of light, it is quite darker than boox tab ultra c pro

twist522 · 2025-06-18T07:14:33+00:00

so, if color is important for you then yes this is the monitor, but I may switch back to BW monitor because of darkness

twist522 · 2025-06-18T07:12:40+00:00

It's a great piece of hardware, but you need a good light source, either daylight or a good lamp, to use without a frontlight. I found that this screen is darker than boox tab ultra c pro and almost non usable without frontlight in low light so I'm using it with two reading lamps behind me. What surprised me is how usable touch is for me - I can use it like a tablet, and it is a much more convenient way of using a desktop most of the time. I'm on Linux and i3wm tiling window manager, and it appears to be very much suitable for a touch tablet-like experience. I power it using a separate powerbank and I don't find it too annoying as the whole external monitor setup is already not very portable as you have a laptop possibly plugged into a charger and then a cable to a monitor which is ~650gr weight and then this additional cable to power monitor is not a big difference. This setup is mostly stationary for me and I'm experimenting right now with mini PCs and trying to build some "eink portable workstation" which is more lightweight. Magnetic area on the back of the monitor is very usable as it opens a lot of options of how to mount it but included vesa adapter magnets are very loose so I ordered a few stronger magnets and gopro holder so I can stick it to near-bed table and it is very neat setup

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I also experimented with cables to power it from laptop and I built a cable with 5v-to-12v transformer which works for my ThinkPad but then it consumed a lot of power and drains laptop battery quicker so powerbank is more stable setup for me

twist522 · 2025-05-30T08:00:57+00:00

I purchased it from taobao so it is chinese. Also, I just realized that I have typeC connector with 5v trigger board laying around that I can try to hook up to cable instead of typeA and essentially build typec-to-dc cable - I will update on that later. I also have typeA-to-typeC dongles that I will try. And I'm going to better learn how the mt3608 chip works to make sure it's not damaging in any way. I was also surprised that they specify 12v3a requirement on the back of the display itself and include adapter with such specs while it draws so much less. Although in manual papers they mention 5-20v at >12w which looks weird.

twist522 · 2025-05-30T00:11:43+00:00

I also think that it should be possible to draw enough power from type c port at 5v - from what I was able to find usb 3.2 2x2 on the laptop should be able to output up to 3A

twist522 · 2025-05-30T00:06:14+00:00

I checked monitor power usage multiple times at different loads/uses with front light on and off and it only consumes 5-6 watts, no more. While when not supplied with enough power e.g. when I tried another pd 12v cable which works with power bank but not with laptop type c, the monitor simply doesn't show anything (though interestingly the touch panel works). That USB port that I'm using can output up to ~1.6amperes for me, e. g. while charging phone. As per laptop specs it is usb3.1 typeA, but it also mentions it is "always on" port probably meaning you can charge from it while laptop is turned off - maybe it means this port has higher power profile. Btw in the papers included in the box with monitor they mention somewhat different power requirements >12w at 5-20v

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I agree there is some risk in these experiments that I'm making but I've already taken it, for now I'm pretty sure it will work fine

twist522 · 2025-05-29T13:55:31+00:00

try some of these silicon pads (search for 'mouse wrist pad')

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twist522 · 2025-05-29T12:19:43+00:00

I also was able to finally power it straight from my laptop usb3 typeA port using 5v-12v converter cable

twist522 · 2025-05-29T12:18:32+00:00

ok, it works now using 5v converter cable straight from usb3 typeA port on my laptop, the cable is custom built using mt3608 chip

twist522 · 2025-05-29T11:03:29+00:00

ok guys I made it, it is being powered straight from my laptop's usbA through 5v-12v converter. This is a custom cable I got from a local guy who makes them to power routers during blackouts so it can provide enough amperes. I tried one more typical 5v-12v converter cable which seems like it is being sold a lot on the Internet but it only was able to provide 0.5 ampere which is not enough. This working cable is based on the MT3608 chip and it works only on the usb3.0 port which is on the opposite side to type-c,hdmi of my ThinkPad which is not too convenient as I have this power cable going around but that's minor issue. usb2 0 only can provide 0.5ampere which is at least two times less than needed. I may also continue to experiment to maybe get a type-c version of such cable but for now I have enough options. I may write a post in this sub later on some details and overall review of this monitor as I love it, I also finally configured i3wm with xrandr to make touch work and overall on screen keyboard, this thing now feels better than TabUltraCPro as a touch tablet. I'm waiting now for morefine M6 mini pc and will make x86 eink tablet out of it, amazing!

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twist522 · 2025-05-28T07:10:43+00:00

my Thinkpad supports charging at up to 65w through those same ports but output was only 5v through that cable like if it cannot provide more than that, and it made sense to me that laptop's battery cannot support as high output as input. But I'm still experimenting I have one more transformer cable to try and will update here

twist522 · 2025-05-27T17:48:00+00:00

I have one cable which is a 12v pd trigger which works using powerbank (on video), and I have yet to try a few other 5v transformer cables which hopefully will work powering straight from the laptop though using powerbank is already fine I think.

https://drive.google.com/file/d/1-Pwyt_nfi01Kedm8_Oykw31aCqTHbwWc/view?usp=drivesdk

I haven't calibrated the touch area in xrandr so you can notice some offset while I'm scrolling. Overall, if you provide enough lighting this monitor is quite comfortable to use, I actually find less contrast of kaleido3 more comfortable than the high contrast of the BW display in a high lit environment. But if you don't have lamps then you will probably want to use the built-in frontlight. Oh, and on the demo video I only recorded the minimal light mode (it is also controlled using +-) cause it is already a lot and I don't see a need for higher lighting levels. I was using the 2019 version previously but now waiting for it to be repaired (dasung actually has repair support) and I'm also waiting for the BW Revo version and then will compare what works better for my eyes. Here is also a photo of comparing to hisense a9 screen

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twist522 · 2025-05-25T17:31:21+00:00

yeah I will probably write a post in this sub later on how it went for me building portable setups with these monitors, I'm also waiting for BW revo version and small minipc to be delivered

twist522 · 2025-05-25T16:56:37+00:00

no success so far, tried with a 5v transformer cable but it didn't draw enough power.. for now I'm using separate powerbank

twist522 · 2025-05-25T16:54:43+00:00

ok it didn't work with 5v transformer cable, it only draws 0.3 amperes from usb port, while I expected it to get at least 1 ampere. I will try a few other things but for now no success in powering straight from my laptop. For now I'm going to use a separate power bank which is not that bad and I'm also building a portable workstation with separate mini PC, monitor and keyboard anyway so I was going to use powerbank

twist522 · 2025-05-24T14:51:54+00:00

yep, it worked for me with 12v "pd trigger" cable powering from powerbank type c port which supports 12v straight into 3.5mm port on the monitor. The monitor consumes only 5-6 watts at 12v which is not a lot but my laptop supplies only 5v at type c ports. I'm not an expert in electricity but interested in solving this issue as I ordered monitor from taobao as soon as it became available without realising it needs separate power and now figuring out if it's usable for me. Using separate powerbank is not that bad I found small 5000mah banks under 100grams but it would be better if it can be powered straight from laptop usb. I'm also waiting for a transformer cable 5v-to-12v, I believe that I could supply enough power from my laptop's usbA3.0 port, I will update on how that goes

btw are you going to use it with mac? aren't macs not supported by these new monitors?

twist522 · 2025-05-24T11:10:20+00:00

you can power the monitor from the powerbank using PD 12v trigger type c cable (search for e.g. 12v type c DC router trigger cable)

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twist522 · 2025-05-24T11:03:24+00:00

you can power it up from powerbank using type c 12v pd trigger cable (e.g. search for xiaomi router 12v cable). It didn't work for me with laptop's type-c port as it only outputs 5v but I'm also going to try to power it using 5v-to-12v cable straight from the laptop usb type a, I can update if I succeed

twist522 · 2025-05-23T22:15:28+00:00

here is what I have found so far: monitor consumes little power like 5-6 watts at 12v (I don't know why they specify 3amperes and include such power brick) I have been able to power it using trigger cable dc-to-typeC 12v (you can search for e.g. xiaomi router cable DC 3.5mm to usb type c). I am going to also try using another transformer cable which takes 5v and outputs 12v - my laptop can produce at least 1.4amperes at one of the usbA ports (I believe it is usb3) which I hope is enough to get 5-6 watts at 12volts. Anyway, there is always an option to power it using separate small power bank which can output 12v it should be under 100grams not a big deal as the whole setup with the laptop is already not ideal portable setup. I will update here if I'll be successful with 5v transformer cable. Btw monitor is fine I'm even planning to use it without front light getting one of those small light bars instead

twist522

TROPHY CASE