Ben Heck's FPGA LCD Driver Hack 

I love how you explained "FP" in FPGA as 'can be programmed anywhere, even on a field' :D

I didn't understand a single thing from this entire video except that you bought a car lcd from ebay :D

The Ben Heck Show Please do more FPGA content!!

I always thought resistance to interference is the reason for differential signaling, rather than the speed granted by low voltage levels as Ben explained. The idea is any kind of EM interference or other power fluctuations would raise or lower the differential pair signals equally thereby leaving the relative voltage between the two unchanged, even as their absolute voltages may fluctuate. Someone correct me if I'm wrong.

Very cool project. Would love to see more FPGA's. I would definitely back this on Patreon!

Hey Ben, why are you guys using an external led for the cyclone rather than oune of those built in? Btw, love the show, much love to you guys

Nice episode, and great results. :) How fast was the clock? Was a logic analyzer not a better choice for this job?

The same screen sould be great for an 8 bit computer, perhaps something like his Apple II build.

Really like how you explain everything, great video and awesome hacking.. The outtakes at the end are pretty funny too, keep it up and have a nice day.

i want to buy this lcd . what number , model for lcd ? mr ben give i know ,please

that is one super expensive oscilloscope

is there a part 2?

Ben - Your vast knowledge on everything electronics is off the planet. Every video I shake my head and smile about how much you know, retain, and explain. :-)

Ah you know...just messing around with my $14,200 oscilloscope.

Dear Ben, this video was very very technical and very explanatory. I really liked how you explained the stuff, good work! Can't wait to see what you will do in the future with this :) Greetings from germany!

FPGAs are great for retro-computing and learning how a CPU works. I am implementing Ben Eater's 8-bit computer in an FPGA in a series of videos on my channel for anyone interested.

This was the best episode yet. I really enjoyed this. l especially like how this episode showed in detail the process of reverse-engineering, and all (or most, anyways) of the guess-work that is involved. And how you just need to jump in there and experiment. In some sense, it's a shame that Ben got it working on the first try. Would have learned more watching him struggle a bit. But hey, I guess it looks good for your sponsor. Finally, you finally gave me an appreciation for what an FPGA can do that a micro-controller or dedicated logic can't. It would take a pretty serious (and expensive) micro-controller to drive that LCD -- if indeed it could be done at all. But it would also take a ton of work to build a circuit up from logic gates to it. The FPGA reduces this to a 25-minute episode. Thanks, Ben!

Awesome!!!! Just awesome! Please Ben, do a complete FPGA tutorial!

I can't believe I have just found this video after two years of searching how to possibly use displays without controllers. This is the best tech video I've watched all year (2017.) Thank you, Ben!

I always thought that at least part of the point of differential pairs was that they are less susceptible to noise because if both wires pick up the same noise, it cancels out when you look at the difference.

can we get a link of that video of a kitten cuddling with a sloth?

It that possible to make driver for smartphone display using this FPGA. If possible then how

This is neat and all........ But where is this kitten/sloth video?

Finally a build that requires some actual skill. You could use DRAM with 2 partitions for 2 frames. 1 frame is constantly written to the screen at the update rate (30 or 60hz) whilst the other is free to access and modify by a microcontroller (cortex M4 or something) which prevents tearing and enables slow microcontrollers to write to the screen with a decent update rate. When the frame has been updated, the FPGA switches the ram access to update the screen with the new frame.

I did something similar, not that difficult using a oscilloscope. I interfaced a graphical calculator lcd, by sniffing the lines and finding out the data format.

just a point of clarification... front and back porch are for the horizontal sync, the pre equalization and post equalization pulses are used in vertical sync.

Thanks! I learned a lot from this. For example I knew something about dif-signaling but I now have a clearer pic of how to read logic states just from your video! I knew what a FPGA was, but the programming and chip and pin management I did not know about! The only thing is when the gate arrays are programmed, does the program have to re-connect all the gates each time the FPGA chip is turned on? Or is static once programmed (like flash memory). Very interesting and makes me wish I had a multi-channel o-scope and a dev board. Only issue is getting a understanding of the programming lol.

OK. So a FPGA is good for figuring out how the signal bus drives the display. Now the real question is if it can be implemented on a cheaper board. A CPLD is out of the question due to the clock rate needed to get all the signals in. If I remember a 112 MHz clock was used for 800x234 resolution. By my calculation (probably wrong as I used simple math) I figure that a 190 MHz clock signal is needed to get all the data needed in for 1024x310 resolution. A simple microcontroller is out of the question for this. Something that can run at upwards of 200 MHz would be needed to drive the 8 wires for the system. Perhaps a small ARM board could be used. Something like this could possibly work: electronicdesign.com/microcontrollers/200-mhz-system-chip-arm-core-targets-lcd-apps It is a 200 MHz ARM based LCD driver chip that is capable of driving a 800x600 LCD. That's 480,000 pixels per frame. At 1024x310 resolution there are 317,440 pixels that need to be driven per frame. If the device can be reprogrammed to drive this odd ball resolution the controller can work assuming it can do 4 pairs of LVDS and accept something like digital RGB input. The controller also promises to be fairly cheap. A LOT cheaper than the FPGA used here. Probably wrong here but thought I'd give it a try. Any ideas on my thoughts? Wrong, right, maybe? I don't know this level of data signalling too well so correct me if wrong.

I'm still amazed how you found the clock frequency and were able to identify each bit. I don't know if you did that quickly or if it took you some time but edited the video. In any case, what an amazing exercise! In my opinion, this kind of videos is truly motivating for future electronics/electrical engineers :D

One of the most interesting videos I've seen recently! Reverse engineering graphic LCD has always been a hard task without datasheets. Also showing how an FPGA can be used as a high-speed driver while most microcontrollers may fail to achieve the task. I hope to see more details, and how to display useful information on the LCD. Thank you for interesting video.

ohhhh man!!...........i wish you were my father....will you adopt me?

Such a high end scope, differential signals and then using the ground leads with alligator clips or how HF-Engineer call it: Antennas. I mean: If it does the job it is good enough, but the signal integrity would be better with shorter ground loops.

Sloth hugs cat: /watch?v=S52Qtlv2o5U

Wow, this shot way over my head. Go Ben. Look, I spent two months designing and printing handlebar-end mirror holders for my motorcycle....Go me...

You could use the composite input, it'll stretch your video funny, just pre-squash the video so when its stretched it looks right. Thats how 16x9 SD content is produced from the same signal as 4x3...

When attaching the ground of the scope probes, is it necessary to attach all of them? Since the grounds are most likely linked inside of the scope, is attaching only a single ground sufficient? I'm referring to the setup at 7:00. Great video, thank you!

Have you seen the droid w (a slightly faster and much smaller raspberry pi Clone) If you want one you better hurry, the production has stopped (only very few left)

You keep explaining FPGAs in a weird way. Basically, when you program a microcontroller you're changing the software, but when you program a FPGA you're changing the hardware.

you are amazing :) i like watching your videos we learn much from you :)

Okay you know what would be cool to make a Portable system using this LCD. Think about it. Ben used anywhere from 3.5" LCD up to 20" LCD why not a short wide 12.2" LCD Portable system. Just saying :)

Also found this on wiki in regards to color depth. 18-bit Almost all of the least expensive LCD displays (such as typical twisted nematic types) provide 18-bit color (64 × 64 × 64 = 262,144 combinations) to achieve faster color transition times, and use either dithering or frame rate control to approximate 24-bit-per-pixel true color,[12] or throw away 6 bits of color information entirely. More expensive LCD displays (typically IPS) can display 24-bit or greater color depth. You said that it uses diferential pairs because of the speed, so when the wiki article says "64 × 64 × 64 = 262,144 combinations) to achieve faster color transition times" that kinda makes sense to me. Question why is it using 7bits instead of 8bits? Right enough beer and youtube commenting for me, Love this video!!!!

Seriously, I don't have the 0.01 of your knowledge in electronic, but damn I love your show (Sorry for my english, i'm french) but you have a great show!! Keep it going!!Seriously!

How would you add a converter to the existing FPGA LVDS coding so that you could input signals like HDMI, Component, VGA, etc? Also, how would you interface a mobile phone LCD with or without a touchscreen? Is adding the touchscreen functionality even possible? I'll say, FPGA programming does not sound that difficult if you know the basics of inputs and outputs, and if you have an oscilloscope. I don't have the money for an oscilloscope, so is there a USB thing that is less than 150/100 dollars that has multiple channels that I can connect to my computer? I would want to do something like this because I might want to make a portable Raspberry Pi thing. I know, there are products out there to help you make it, but I want it to be as thin as possible (because I might want to shove the circuitry in a GBA SP).

Another Great Vid. Keep coming to watch something go " FiiiZZZZZzzzzzzz " but yet again.. Ben get it working ...

Differential signalling not only increases speed, it also REDUCES NOISE (increases noise immunity) ! ;)

programming fpga's.... will learning to do so drive me insane? will I end up licking the windows in a bus when travelling? will I become one of those eccentric types, who mutter incoherent oaths whilst simultaneously voiding my bladder? will I need to have more than two cats suffering from advanced hallucinations, running around my house chasing invisible mice? a tinfoil juggernaut of synthetic otter chocolates bestowed onto my refrigerator's dingle berries.... let's see how deep this rabbit hole goes then, shall we? does element14 sell advanced geek wear - aka: adult nappies? wibble if EOL != sanity return alls_well_happy_days else return to_sender_address_unknown

Hey Element 14, could you MAKE a video on how to manually program a FPGA? How can we set each bit manually, without a programmer? Is it the same as an eprom? Thanks!

6 bits of blue 6 bits of red 6 bits of green.... i know im prolly not the first to "AH MARK OF THE BEAST!" in the comments but heh heh i didnt know it was like that.

My only real issue with this is that it took a $15K 'scope to figure out the workings of a $100 4:1 LCD display. If only there were more cost effective, multi-channel solutions for the avid electronics hobbyists....

Ben, new subscriber, most of what you do goes right over my head, but I love watching and hopefully something valuable will sink in. How much was the lcd? Are you going to give COLOR DMD a run for their money ?

Actually a legitimately useful application: I've got so many LCD's lying around with obnoxiously large driver boards and composite input, implementing it on an FPGA is a much nicer fix than hacking in the original board to a project.

According to the (really useful) panelook.com site, there is only one LCD screen with a 1024 x 310 resolution, so this must have been the one used in the video... www.panelook.com/TX31D16VM2BAA_KOE_12.2_LCM_overview_12075.html

Can considerer a i2C signals of the SDA an SCL as a differential signals too? They build words too... Or is a simetrical voltage in a bias? I am an amateur forgive me :) Thanks for your videos!!

So frustrating when 90% of what you explain is right on the fringe, I can almost grasp the concept but then it eludes me! I mean I know my mind doesn't udnerstand physics but still it bother me... Gonna keep watching though, your build are way to cool not to.

Having not much experience with oscilloscopes, I wonder why the signals are so distorted @7:22 ? Does it come from the high frequency, and thus the reason why they chose differential pairing? I'm sorry for stupid questions :)

Hello, ben, when you gone put some PinMame or Visual Pinball to this?, Some kind of Mini Virtual Pinball Machine with 2 screens, that its ready to go :-)

I've decided to take up nuclear science with a pastime hobby of Chinese Language studies... might be easier..

Red is green. Got it. I'm used to this kind of thinking. Things being backwards and not what they at first appear to be. From inverse relations and counter-intuitive concepts.

Number plate! For cars. Just saying this would be good for number plates in the uk. What's your thoughts Ben!

I am very surprised you cared about decoding screen timings. you can get them from Vesa GTF or CVT. why bother to decide if from oscilloscope? this is waste of time and effort.

Hi ben, many people have been saying just buy some LVDS boards of ebay and for the most part there cheap, but my issue with those are that you never know if your going to get full speed of the LCD, so i like your idea of using an FPGA as it has the more then enough power to handle any LCD and any res at any speed possible, you could also make a program to test LCD with it so. So i really do like your idea and shall try it sometime as i have a grave yard of LCD that most likely have blown boards. are you able to share a link of your program that you made for the FPGA?

Hello I would like to use that LCD to build Synthesizer , Is this Touch screen like the Ipad ? I am looking to build a synth with a touch screen is this possible ?

I want to do this with a different display, I am sure this will help.

What about the Color DMDs that have come out for DMD style pinball machines? Could you not code up your own pinball machine and do your own code? There is even an option to have it look like the original DMD with the dots or you can have the option of no dots. But what is a DMD with out the dots right? ;)

Ben writing verilog? Reverse engineering digital video signals? What show is this? Seriously, though, systemverilog ftw

I really like this video, it sort of pertains to a project I am trying to complete. I really want to use old laptop LCDs to use in multiple applications. I'd rather not use a controller board from eBay. What can I do to make something like this?

Shouldn't the clock give an impulse, so rise or fall, on every single bit instead of this weird 4 bits high, 3 bits low???

17:02 wow that massive bag of cocaine behind him.

So would it be possible to convert an HDMI signal using the same FPGA or would other hardware be needed?

EERM why not just pull up the data sheet instead of probing around?

Ben, On the revisited raspberry pi mame project next episode could you talk more in depth about batteries and how to power a portable. I'm building one myself and don't know what to do.

Wow! Awesome! I really enjoyed seeing how this video... GatorAid LOL

Been looking to create a similar project with a Gameboy Advance but I can barely find information on it. There are hackable converters but they're impossible to find. At the very least, I need a resource for the pinout of the Gameboy Advance motherboard so I can reverse engineer it like Ben does here. Anyone have any leads on where to find such a thing?

Ok so now it is working on a FPGA. How do i implement it in a project? Can i now transfer the data to a seperate chip that handels all the code on the pcb? Grate video, well explained.

I think that you should try to use this display for a pinball machine. The DMD's are so expensive these days so it would be nice to have a cheap way to replace one and also having the possibility to make it another color. Cheers!

I'm just curious Ben, how long did you spend figuring out where everything you needed to know about the LCD screen to do this and if decoding the signals was a big issue?

I was really hoping this was a part 1 of 2. Obviously, you need a way to input a different signal for frame pixel data and have the FPGA translate it out.

Seriously the Thumbs up is kinda falling short for me with a video like this. This is pure electronic geek porn! I am kinda wondering you must have read the datasheets for the chips on the driver board as part of the reverse engineering process?

Anyone know the model number of this LCD panel ? I am trying to find it only but I can find only a 10" version

sir Ben, can i have some tips in learning verilog, what is the best resources, books or tutorials to read or follow so that i can fully understand verilog, we use it in rtl and verification, advance thanks, and more power! sorry for the english :)

this is constructive criticism. I know what you did I saw part of how you did it ...but i thought the aim of the vid is to show your viewers how they too can go out there and buy that suff and do it themselves. I know you failed at that. If this vid is not for beginners I think you should warn us . If not do a part 2 and maybe 3 to get the point over or just do a longer video. Thanks for your contribution. I really mean that.

oh my, that's so cool :) i am playing around with arduino and naked controllers and stuff, but where i can get decent a fpga board?

I have a quick question, where should i buy parts for electronics projects i have?

A really great video. I've criticized your content, but that was a great video. I like this new direction a lot!

Why was it necessary to sniff out those signals with the oscilloscope? Isn't there a standard for LCD signals?

How can you make a multiple hdmi input tv? I am wanting to make a rear projection tv with my own diy made projector so I want to be able to have multiple inputs.

This was way over my head but nonetheless I thought it was way cool and super interesting.

So this is great and all but how do you feed the fpga an actual video signal?

Alyson rocks. You should bring her on the show more often. Awsome hack. Did understand that you did something and wish i had the knowledge and tools to do the same.

hi i need a help to you sir..... i want to install computer vga lcd on embroidery machine there is already small lcd working on that machine please help me

I'm sure this was a great video, but RU-vid won't let me see it, won't even let me download it and watch it.

i had an old busted laptop and i wanted to reuse the screen the manufacturer has kindly put labeled test points with all the signals now i just need to know what the letters actually mean like RX2P

The interesting part like the fpga programming was only showed a very tiny time. And how would one add a hdmi in to it?

There is any post with more info on this? Per example the fpga source code? Thank you

*Nods and pretends he understands any of this.* I think I'll just pay for someone to do stuff like this.

What is the minimum Oscilloscope analog bandwidth and sample rate to do this?

How can you use thar display for a custom dashboard? Thanks in advance.

That looks like a 21:9 ratio and that would be great for personal movies on a plane or passenger in a car.

Is there a 'crude' way to do this without a scope that is quicker than trial/error by plugging the wires into a breadboard and testing?

I'm intrigued, tell me more about this cat and sloth video........