6 ms·
Building a panel out of e-ink electronic shelf labels
- wzdd 4y agoLove the simplicity of the circuit with the daisy-chained uart lines and the use of a time-to-live counter to determine the target so you don't need to give each one an ID.
- tiagod 4y agoAnother approach to this, seen in addressable LED strips, is to have two commands - SET and RESET - where the first call to SET after a RESET will change the LED colour, and the next ones will just pass the value to the next node. RESETs will always be passed to the next node, resetting the whole strip. This doesn't require the hop counter.
- RL_Quine 4y agoThe APA102 is probably even simpler, it acts as a 1 byte shift register register per LED and passes the bytes down the chain without needing to really know the total length, there's some special case to latch all the data into the output registers. I'm fond of that design because it needs no timing specific input, you could easily input the data with push buttons if you cared to.
- sowbug 4y agoGE Color Effects G-35 Christmas lights from about a decade ago used a similar scheme, except that they boot up in an "enumerate" state and use the first transmission to each figure out their own unique address (or pass the messages down the line). After that, they can each be addressed individually. (Edit: jgrahamc beat me to it!)
- ryanmercer 4y agoI'd run it off of a LiFePO4 (bioenno or something), but that's the ham in me (also I'd probably give it powerpole connectors just to further justify how much I spent on my crimpers haha). Really cool!
- deleted 4y ago[deleted]
- jgrahamc 4y agoI love stuff like this. I once went way too far down a rabbit hole with addressable Christmas lights. https://blog.jgc.org/2011/11/turning-ge-color-effects-g-35-christmas.html https://blog.jgc.org/2011/11/turning-ge-color-effects-g-35-c... These are also serially linked but the first step is to give each lamp an address and then messages just get passed on until consumed by the appropriate lamp.
- jacquesm 4y agoThat's really neat! I wonder if (and how long) they would run off a supercap or harvested wifi energy.
- uptime 4y agoJust came to say that I am loving rbaron’s write ups - thank you introducing me to them @frxx.
- frxx 4y agoI stumbled across them today. Glad I could make your day better.
- londons_explore 4y agoI never quite understood why shops use those electronic shelf labels. Most of them can't be updated by someone in the store headquarters remotely. Someone has to take a bluetooth programmer device around and program each one by hand. And if they're doing that, they might as well just take a handheld label printer or sheet of labels. Benefit of the labels is they're clearer than e-ink, brighter, and more colorful (more sales)
- londons_explore 4y agoI notice that the electronic labels are more common in poorer countries. Perhaps they help prevent fraud in some way (eg. shop assistant 'accidentally' misprices an item, and then their friend buys it?)
- aiisjustanif 4y agoIs it less wasteful than throwing away labels?
- londons_explore 4y agoThey only last 5 years. The an electronic label has to cost more both environmentally and financially than ~500 paper labels.
- HeyLaughingBoy 4y agoWell, I don't know about environmentally, but nothing suggests that they cost more (financially) than paper labels. If there wasn't an overall benefit, why would the stores use them?
- nicoburns 4y agoWhat's the failure mode?
- tiagod 4y agoI doubt it, especially as they're not going to keep these labels forever. I would be interested is seeing real numbers, but I would bet you'd need A LOT of price changes to a product to offset the (monetary, carbon, ...) cost of the electronic label.
- Moosdijk 4y agoWhat a coincidence that this [1] popped up in my youtube feed today. [1]https://youtu.be/CLmotCeMlq0 https://youtu.be/CLmotCeMlq0
- solarkraft 4y agoThis is cool. I like E-Ink displays and also have plans to build a wireless display like this, but was/am stuck on how to receive data while also sleeping as deeply as possible, so the linked page about advertising looks helpful!
- solarkraft 4y agoI'm super interested in these ESL displays, but couldn't really find any (the few I found are very expensive per piece). Are there any special keywords or sources for finding them in Europe?
- gigel82 4y agoDitto, I'd love to get my hand on some of these at the prices he found them ($1.4/unit). There's nothing in the usual places (eBay, AliExpress), and the raw e-paper units (no battery or micro-controller, or case) start at $5.