PieRas
Posts: 13
Joined: Thu Jul 07, 2016 6:34 pm

Direct display connection

Thu Aug 04, 2016 3:14 pm

Hi...

I'm trying to connect an e-ink display to the Raspberry Pi but I would like to know if it's possible to connect the physical LVDS / JST to the Raspberry Pi somehow (through SDI, converters or something else)

do you think it's possible to solder wires between the LVDS / JST and GPIO pins? or maybe there's a special Raspberry Pi edition which is compatible with LVDS / JST connection?

any answer will be appreciated, and other ways to connect it are welcome as well :P

thanks :D raspberry rulz

fruitoftheloom
Posts: 27225
Joined: Tue Mar 25, 2014 12:40 pm

Re: Direct display connection

Thu Aug 04, 2016 4:04 pm

PieRas wrote:Hi...

I'm trying to connect an e-ink display to the Raspberry Pi but I would like to know if it's possible to connect the physical LVDS / JST to the Raspberry Pi somehow (through SDI, converters or something else)

do you think it's possible to solder wires between the LVDS / JST and GPIO pins? or maybe there's a special Raspberry Pi edition which is compatible with LVDS / JST connection?

any answer will be appreciated, and other ways to connect it are welcome as well :P

thanks :D raspberry rulz
Do you know the manufacturer / model of e-ink disly and voltage requirements ??

.
Take what I advise as advice not the utopian holy grail, and it is gratis !!

PieRas
Posts: 13
Joined: Thu Jul 07, 2016 6:34 pm

Re: Direct display connection

Thu Aug 04, 2016 4:42 pm

The e-ink display is ED060SC4, voltages are +22V, -20V, +15V and -15V
I think I need the 3.3V pin for power

Heater
Posts: 19236
Joined: Tue Jul 17, 2012 3:02 pm

Re: Direct display connection

Thu Aug 04, 2016 4:51 pm

Seems all the information you need is here: https://github.com/PetteriAimonen/ED060SC4_driver
and here: http://essentialscrap.com/eink/
Slava Ukrayini.

klricks
Posts: 8552
Joined: Sat Jan 12, 2013 3:01 am
Location: Grants Pass, OR, USA

Re: Direct display connection

Thu Aug 04, 2016 5:12 pm

PieRas wrote:Hi...

I'm trying to connect an e-ink display to the Raspberry Pi but I would like to know if it's possible to connect the physical LVDS / JST to the Raspberry Pi somehow (through SDI, converters or something else)

do you think it's possible to solder wires between the LVDS / JST and GPIO pins? or maybe there's a special Raspberry Pi edition which is compatible with LVDS / JST connection?

any answer will be appreciated, and other ways to connect it are welcome as well :P

thanks :D raspberry rulz
You cannot direct connect the screen to the RPi. You will need to get a driver board (if one exists) to convert from LVDS to HDMI.
Unless specified otherwise my response is based on the latest and fully updated RPi OS Bullseye w/ Desktop OS.

Heater
Posts: 19236
Joined: Tue Jul 17, 2012 3:02 pm

Re: Direct display connection

Thu Aug 04, 2016 5:21 pm

Yes you can. At least according to this schematic which shows a direct connection to an STM32 : https://raw.githubusercontent.com/Pette ... matics.png

Also has the circuitry for the various power supplies.

Of course such a hook up won't magically get Linux to use the display. ...
Slava Ukrayini.

fruitoftheloom
Posts: 27225
Joined: Tue Mar 25, 2014 12:40 pm

Re: Direct display connection

Thu Aug 04, 2016 5:24 pm

klricks wrote:
PieRas wrote:Hi...

I'm trying to connect an e-ink display to the Raspberry Pi but I would like to know if it's possible to connect the physical LVDS / JST to the Raspberry Pi somehow (through SDI, converters or something else)

do you think it's possible to solder wires between the LVDS / JST and GPIO pins? or maybe there's a special Raspberry Pi edition which is compatible with LVDS / JST connection?

any answer will be appreciated, and other ways to connect it are welcome as well :P

thanks :D raspberry rulz
You cannot direct connect the screen to the RPi. You will need to get a driver board (if one exists) to convert from LVDS to HDMI.
It is not a LVDS Display and this e-ink display requires a far greater voltage than 12V4A LVDS generally requires... +22 V, +15 V, -15 V and -20 V.
.
Take what I advise as advice not the utopian holy grail, and it is gratis !!

PieRas
Posts: 13
Joined: Thu Jul 07, 2016 6:34 pm

Re: Direct display connection

Thu Aug 04, 2016 7:32 pm

I did follow the details in essentialscrap, but you cannot buy STM32 anymore since it's discontinued so maybe it's possible to use the GPIO pins as a microcontroller...

I think he mentioned that it's possible to use the part FH26-39S-0.3SHW to connect the LVDS directly to a PCB so maybe if I buy this part which is available today I can solder it to the GPIO pins?

I don't really know...what do you guys think?
I'm trying to follow the essentialscrap instructions but use a Raspberry Pi, and I don't have any skills so I hope I won't break anything :roll:

thanks :D raspberry rulz

Heater
Posts: 19236
Joined: Tue Jul 17, 2012 3:02 pm

Re: Direct display connection

Fri Aug 05, 2016 1:16 am

If you can't get that STM32 anymore there are many other STM32 that will work just as well, peraps with some software tweaking.

But what is this http://www.digikey.com/product-detail/e ... ND/2640836 ?

Anyway, I was not suggesting you have to use exactly the MCU used at https://raw.githubusercontent.com/Pette ... matics.png

But that schematic shows what connections you need and what to do for the various power supplies.

Then he has the driver software that you can adapt and run on the Pi.

This still does not get you a display that Linux can use. For that you need to make a Linux driver. But you should be able to draw on it from your own code.
Slava Ukrayini.

PieRas
Posts: 13
Joined: Thu Jul 07, 2016 6:34 pm

Re: Direct display connection

Fri Aug 05, 2016 8:26 am

a Linux driver? you mean I can't connect it and use it as a desktop display?
How can I code it? I've never done coding, where can I read any instructions about Linux driving for an e-ink desktop display?

Other MCU's means higher budget, if it's possible to connect the display directly to the Raspberry Pi then why buying them?


thanks :D raspberry rulz

Heater
Posts: 19236
Joined: Tue Jul 17, 2012 3:02 pm

Re: Direct display connection

Fri Aug 05, 2016 8:42 am

Well, just because you connect something to a bunch of GPIO pins does not mean that Linux knows what's out there.

You would need a kernel driver to get the frame buffer onto your display. There must be drivers like that out there already because people hook little LCD screens to the GPIO. No idea if anyone has actually done it for your display.

If not you could perhaps adapt a display driver from some other display to drive yours.

If you have never done coding before you have a long road ahead....
Slava Ukrayini.

Heater
Posts: 19236
Joined: Tue Jul 17, 2012 3:02 pm

Re: Direct display connection

Fri Aug 05, 2016 8:47 am

Here is a guy who was trying to do this already https://hackaday.io/project/10161-6-inc ... nk-display

Does not look like he got very far.
Slava Ukrayini.

PieRas
Posts: 13
Joined: Thu Jul 07, 2016 6:34 pm

Re: Direct display connection

Fri Aug 05, 2016 9:17 am

Can't I edit the driver that was presented in essentialscrap to Raspberry Pi?

Is it possible to display the desktop in a normal speed like a regular ebook reader?

thanks :D raspberry rulz
Last edited by PieRas on Fri Aug 05, 2016 10:13 am, edited 1 time in total.

Heater
Posts: 19236
Joined: Tue Jul 17, 2012 3:02 pm

Re: Direct display connection

Fri Aug 05, 2016 9:49 am

Certainly you can edit that driver. How hard it might be to get it working is another matter.

That driver on essentialscrap is code for a STM32L1 micro-controller. It is not anything like a kernel driver. Probably does not actually do what you need in a Linux kernel driver anyway.

As I said, you could possibly take the source from some other display that connects to the GPIO and use the information/bits of code from essentialscrap to create a Linux driver.

This all sounds far from trivial. Especially if you have not been writing a lot of C already.
Slava Ukrayini.

PieRas
Posts: 13
Joined: Thu Jul 07, 2016 6:34 pm

Re: Direct display connection

Fri Aug 05, 2016 10:13 am

is there an easier way to write the kernel driver?
can I use Python?


thanks :D raspberry rulz

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