Shorter display cable

@duwudi Do you have the specification for the display port available? I’d like to know so I can maybe build my own by taking measurements and running it through JLCPCB and the I could post the adapter as open source? Hehe :wink:

@Supernovali sure, see attached pinout. You’ll notice a few differences between our pi-top Display Port and the USB-C spec but in terms of signal type on the various pins it’s compliant - we just don’t have the reversible feature that USB-C has (for many, many reasons it just didn’t make sense for us to go to that trouble).

Please note that we have the HDMI HPD pin pulled up to 10k to comply with CC pin spec of USB-C (to inform downstream devices we can supply 3A at 5V), but in our HDMI adapter and in the FHD Display this goes through a NOT gate to flip it to match HDMI HPD spec.

2021-02-07%2011_06_47-pi-top%20%5B4%5D%20Architecture_%20Lucidchart

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Sweet! So for the hpd pin, the display and the pi-top invert the signal so it’s just buffered? Or the cable includes the not gate and the pull up is done on the hardware?

Yeah our display inverts it, but we also have to invert it inside the HDMI adapter that plugs onto the Display Cable to allow it to be compatible with other HDMI displays

Also if you want to design the adapter, I’d be happy to do the mechanical design and give you a layout DXF. We just need to find part numbers and STEP files for the vertical connectors. If you want to have a call to kick this off send me a DM :handshake:

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I think OSHPark would be great for this effort if someone can do the design.

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Me and @Supernovali have been collaborating on the design for the shunt adapter. He’s already finished a first version and waiting on prototypes - if anyone wants to test them let him know :+1: (although we only have limited number at this time)

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@duwudi @Supernovali I’d certainly be up for testing if ya need somone to :slight_smile:

Is compatible with the foundation plate or just the pitop by itself docked

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Currently just the pi-top by itself. But now that you mention that it can be docked (don’t currently have the robotics kit) I might be looking into making a version that is compatible with both

@Supernovali I do have an idea for a board, if ya ok for me to DM ya about it

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Go for it :slight_smile: I’m all ears :ear::joy:

@duwudi @Supernovali I would love to test the shunt! Please let me know if you can spare one.

I’d also be happy to test/pay for one.

Hey guys! I just finished up the first prototype and I have to make a second one due to a couple of mistakes and errors. I’m currently planning on next weekend for the first round of testers. I currently already have 5 testers which is the my testing cycle, 2 of which already have display issues and 2 which have known good machines, plus the founders of pi-top to share one.

Currently, building a single display bridge costs about 6 dollars to make due to the low quantities. But, if you would also like to be part of the testing team, Id be happy to include you guys for the preproduction prototypes, with no additional cost besides the cost of shipping out to you. (My plan was when I get the initial prototypes done, to make one more iteration to make sure that the final kinks are worked out, and do the testing on my own, granted the initial prototypes work with other people’s hardware)

@jwktje and @modulusx, when I get the second iteration tested, I’ll PM you if you’re still interested to get the preproduction prototypes. Preproduction prototyping will be ready to go in about 3-4 weeks. And then after that, it will be available on Amazon. I’m not sure what the shipping rates would be like from Amazon, but if you know about how much it costs/how long shipping takes to your area from SLC , Utah, you can make a decision based off of that. My plan is to to sell for a very small margin, maybe 50%. That barely covers the costs for amazon’s 14% cut and electricity/energy producing, but this is really just a way to get my company name out into the community. Final version will then be between 10-12 USD. I’m not sure how much amazon would charge for shipping.

Hopefully these factors help you guys to decide if it’s cheaper to wait for the final product or cheaper to get the preproduction prototype :wink:

@Supernovali Great man! I’ll wait for that PM and will very likely still want that prototype at that point. I don’t might the higher shipping that much. And very cool that you and your company are making this for the community, great job all-round

Great to hear you’re well on the way to solving the portability challenge! I’d like to be part of the testing team.

Recently I nearly dropped the docked Pi-Top and Display when the display cable snagged on a door handle!

So I’m keen to test early prototype versions asap and am prepared to keep sharing the cost and paying for shipping, until any problems are ironed out.

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No coat for the actual parts necessary, just shipping for the preproduction version. And I’m glad you were able to save it! I’ve had my son accidentally snag them too. That’s what got me into doing this particular project haha

Dear pi-toppers,

It has been a couple months. … “Where did ‘we’ get to with the short display cable / adapter option?

Mine is constantly being knocked out … as is the power cable! … Looking for a neat solution

Thx

Hi @nannerbm60, @Supernovali was working on a small dongle - not sure where he’s at with that but maybe he could share the design files (I know life has been busy for him lately!)

In terms of the short cable that we said we’d produce on our next run - we haven’t had any need to produce more yet since we had to produce a lot on the first batch (cable MOQs are high) and also DIY Edition has been really popular which lessens the need to make more. As soon as I have news on that I’ll be sure to update, but the best solution in the short term is the small PCB that @Supernovali was working on

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Yeah, sorry about the slow response. As far as the display bridge goes, there are 2 issues. First, I’m back in school and trying to balance life. It isn’t that I don’t have free time to work on it but I am limited. The second is supply. To continue with the design, I need more connectors. Due to the demand in computer components, my previous order of 50 units hasn’t been filled and was ordered back in April. I will either need to wait until the shortage clears or start over from scratch with a new supplier and connector. The other suppliers are extremely expensive compared to this one. So we will see what happens.

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