Price poll. Display, touch, base board, FPC and adapter, spacer, 10mm studs, software, shipping.

I would pay around 70€ ($80)
20%
1
I would pay around 60€ ($69)
No votes
0
I would pay around 50€ ($58)
40%
2
I would pay around 40€ ($46)
40%
2
I'm interested but I need <feature>. See my posting.
No votes
0
I've seen this but I'm not interested because <no-go>. See my posting.
No votes
0
 
Total votes: 5
Janka
Posts: 11
Joined: Mon Apr 21, 2014 9:12 pm

Soon to buy? HDMI to 5" PCT display baseboard

Mon Apr 25, 2016 2:19 pm

Hi,

for a project I made a small baseboard which piggy-backs a Raspberry B+ (and A+, haven't checked Pi2 and Pi3 yet) on the back of a 5" display. The basic idea was to have a very compact way to mount a Raspberry on a display, and that package into some hole you cut into a custom casing. I need dozens to hundreds for my own project, but maybe it's suitable for the general public, too.

Feature list:
  • Display resolution 800x480, 24bit, 110mm x 67mm display/touch area.
  • Capacitive 5-point multitouch; a driver is included as simple, stupid, heavily commented linux kernel source code (against 3.10.28, but should work with later versions, too).
  • Dimable LED backlight. Done with a PCA9530, simple control program source included.
  • Display, backlight controller and and touch controller connect to HDMI, all other ports of the Pi are available to the user, no IRQ pins or configuration required.
  • Low profile —13mm from front to Raspberry mount studs on the back—, frame 121mm x 71 mm, outer dimensions (touch glass) 127mm x 86mm.
  • Small-size HDMI to FPC adapter and FPC included, does fit into frame size when plugged.
  • SD card plugged into the Raspberry fits within the frame, same with plugged ethernet or USB cables, it's all very compact.
  • Four 2,5mm mount studs for the Raspberry Pi B+ (and A+, Pi2, Pi3), 10mm extention studs can be used to mount any other I/O module on top of the Pi.
  • Powered through the mounted Pi's 5V/GND test points, other power source not required.
  • Needs about 200mA from 5V at full brightness.
  • Ten mount holes for mounting the whole package into a casing, spacer included. Can be used with 2,5mm nuts and bolts, cramps or similar.
  • (Optional: 8 Ohms 0,5W mono amplifier connected to the analog audio output test point. I need this for my project but not sure whether other people find it useful.)
I have a price for the volume I need myself (medium/high but okay for my customers) but getting a bigger user base for this may make it much cheaper.

People who are interested, please just take the price poll and/or give a comment. No kickstart required. This stuff is already done, the only decision I have to make if I get myself into additional trouble by selling it to the general public.
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User avatar
CarlRJ
Posts: 599
Joined: Thu Feb 20, 2014 4:00 am
Location: San Diego, California

Re: Soon to buy? HDMI to 5" PCT display baseboard

Tue Apr 26, 2016 12:11 am

Your design looks impressive. I didn't know it was possible to bring the touchscreen data back across the HDMI connector. Unfortunately, you're sort of wedged in between the Adafruit PiTFT displays, which are smaller but start around $35, and the official 7" display that runs around $80, and both of those are known quantities that have software support in the Raspbian distribution already (neither is exactly plug-and-play though); I suspect your market would be primarily others who are incorporating Pi's into some other product, like you're doing. If I needed another display, though, I'd be tempted. The easy path to (some) sound capability is a nice selling point, as is leaving the GPIO bus entirely open.

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

Re: Soon to buy? HDMI to 5" PCT display baseboard

Tue Apr 26, 2016 1:27 am

Janka wrote: ....
[*] Powered through the mounted Pi's 5V/GND test points, other power source not required.
....
Will this work on 2B & 3B?

Are the power points 'friction fit' or soldered?
I think the test points PP1 (5V), PP2 (5V), PP3 (GND) and fuse F1 are in different physical positions on B+ vs 2B & 3B?
Unless specified otherwise my response is based on the latest and fully updated Raspbian Buster w/ Desktop OS.

Janka
Posts: 11
Joined: Mon Apr 21, 2014 9:12 pm

Re: Soon to buy? HDMI to 5" PCT display baseboard

Wed Apr 27, 2016 10:55 pm

CarlRJ wrote:Your design looks impressive. I didn't know it was possible to bring the touchscreen data back across the HDMI connector.
The HDMI has a DDC (as VGA and DVI have), which is plain old I²C. Usually only the EDID eeprom sits there, but you can connect other I²C chips, too. Fortunately the Raspberry allows to access this I²C from the CPU, too (though not enabled in the default configuration). The touch controller the display has is a FT5316, so it's dead simple to read out. Only drawback is existing I²C drivers for touch controller chips need an IRQ line, which the DDC obviously don't have. I could have connected it to an I/O pin but I wanted to stay clear from them so I made a custom touchscreen driver which polls the chip. It has a automatic slow/fast poll mechanism so it doesn't introduce unnecessary many timer interrupts when there's no touch.
Unfortunately, you're sort of wedged in between the Adafruit PiTFT displays, which are smaller but start around $35, and the official 7" display that runs around $80, and both of those are known quantities that have software support in the Raspbian distribution already (neither is exactly plug-and-play though); I suspect your market would be primarily others who are incorporating Pi's into some other product, like you're doing. If I needed another display, though, I'd be tempted. The easy path to (some) sound capability is a nice selling point, as is leaving the GPIO bus entirely open.
I know. I started this last year, right before the 7" display came out. But I needed something compact anyway, the product I use this for has a number of poles each one with a small display.

About the price; well, I am *above* the 70€/80$ with my net cost price right now. But for now the converter is still made in Germany, as soon we can put this together in China, it should get much cheaper.

Janka
Posts: 11
Joined: Mon Apr 21, 2014 9:12 pm

Re: Soon to buy? HDMI to 5" PCT display baseboard

Wed Apr 27, 2016 11:02 pm

klricks wrote:
Janka wrote: ....
[*] Powered through the mounted Pi's 5V/GND test points, other power source not required.
....
Will this work on 2B & 3B?
I think the test points PP1 (5V), PP2 (5V), PP3 (GND) and fuse F1 are in different physical positions on B+ vs 2B & 3B?
The Pi2 and Pi3 are ordered and will arrive soon, I hope. If the test point layout changed, I will make another version of the board which fits all.
Are the power points 'friction fit' or soldered?
The base board contacts the Pi with appropriate test point contacts with a spring in it (of course, these are soldered on the base board).

User avatar
TonyD
Posts: 448
Joined: Thu Sep 08, 2011 10:58 am
Location: Newcastle, UK
Contact: Website

Re: Soon to buy? HDMI to 5" PCT display baseboard

Thu Apr 28, 2016 1:13 pm

It would useful it you could include mounting holes for the Raspberry Pi Zero as well.
Tony

Janka
Posts: 11
Joined: Mon Apr 21, 2014 9:12 pm

Re: Soon to buy? HDMI to 5" PCT display baseboard

Sat Apr 30, 2016 1:34 pm

Ah, there are more changes needed for that. The Pi Zero has a Mini-HDMI connector at a different position and it has way different test points on the back. Sure, it would be possible to do a layout *only* for the Pi Zero. What makes me wonder about the usefulness is the display is big compared to the Pi A+ already, and compared to the Pi Zero, it would be huge. There is not much sense in using the Pi Zero when you could use the Pi A+.

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