Linux embedded plus small TFT: ready-to-use solution

I need to develop a product based on Linux embedded (because I need to 
communicate with a 4G modem through USB and I have the drivers for Linux).

So I'm searching an almost ready-to-use solution for this product (I 
should minimize design cost even if this increases the price of a single 
product... I will produce only 10-20 pieces at the moment).

The system should have only a USB host port (for 4G modem) and a small 
(2.8-4.3") display TFT with resistive touch panel.
The display should be mounted on a panel.

The best would be to have a SOM solution, so I can design my simple and 
custom carrier board where to mount the SOM, the 4G modem, power supply 
and so on.
However I could use a complete (with connector) board (I'll interface it 
with a my custom board).

The most important thing: I don't want to waste too much time to make 
Linux and display running. I'd like to write only the final application. 
Linux and display should run from the beginning.

The GUI will be very simple: only about 10 different screens with some 
settigs and status info.  No more.

Any suggestion?

On Wednesday, September 7, 2016 at 4:16:16 PM UTC-7, pozz wrote:
> I need to develop a product based on Linux embedded (because I need to 
> communicate with a 4G modem through USB and I have the drivers for Linux).
> 
> So I'm searching an almost ready-to-use solution for this product (I 
> should minimize design cost even if this increases the price of a single 
> product... I will produce only 10-20 pieces at the moment).
> 
> The system should have only a USB host port (for 4G modem) and a small 
> (2.8-4.3") display TFT with resistive touch panel.
> The display should be mounted on a panel.
> 
> The best would be to have a SOM solution, so I can design my simple and 
> custom carrier board where to mount the SOM, the 4G modem, power supply 
> and so on.
> However I could use a complete (with connector) board (I'll interface it 
> with a my custom board).
> 
> The most important thing: I don't want to waste too much time to make 
> Linux and display running. I'd like to write only the final application. 
> Linux and display should run from the beginning.
> 
> The GUI will be very simple: only about 10 different screens with some 
> settigs and status info.  No more.
> 
> Any suggestion?

Raspberry Pi 3.  We are using hdmi display, but there is a display port on-board.  I am sure you can find an LCD screen for it.  We are using T-mobile USB 4G modem, works fine with the network and modem manager.  The only problem is that the USB modem would time-out when not in use for a while, and only reboot can bring it back on line.  We might end up using a network keep-alive connection to keep it up.

We only need one USB host for normal op, but a second port is handy for keyboard when we messed up the 4G or Wifi connections.  RPI has 4 USB ports.

Il giorno giovedì 8 settembre 2016 01:55:01 UTC+2, edward....@gmail.com ha scritto:
> On Wednesday, September 7, 2016 at 4:16:16 PM UTC-7, pozz wrote:
> > I need to develop a product based on Linux embedded (because I need to 
> > communicate with a 4G modem through USB and I have the drivers for Linux).
> > 
> > So I'm searching an almost ready-to-use solution for this product (I 
> > should minimize design cost even if this increases the price of a single 
> > product... I will produce only 10-20 pieces at the moment).
> > 
> > The system should have only a USB host port (for 4G modem) and a small 
> > (2.8-4.3") display TFT with resistive touch panel.
> > The display should be mounted on a panel.
> > 
> > The best would be to have a SOM solution, so I can design my simple and 
> > custom carrier board where to mount the SOM, the 4G modem, power supply 
> > and so on.
> > However I could use a complete (with connector) board (I'll interface it 
> > with a my custom board).
> > 
> > The most important thing: I don't want to waste too much time to make 
> > Linux and display running. I'd like to write only the final application. 
> > Linux and display should run from the beginning.
> > 
> > The GUI will be very simple: only about 10 different screens with some 
> > settigs and status info.  No more.
> > 
> > Any suggestion?
> 
> Raspberry Pi 3.  We are using hdmi display, but there is a display port 

If he doesn't need WiFi, BT, or eth a Rpi Zero is definitely cheaper.

Bye Jack

Il giorno giovedì 8 settembre 2016 11:24:33 UTC+2, Jack ha scritto:

> > > Any suggestion?
> > 
> > Raspberry Pi 3.  We are using hdmi display, but there is a display port 
> 
> If he doesn't need WiFi, BT, or eth a Rpi Zero is definitely cheaper.
> 
> Bye Jack

For example:

https://learn.adafruit.com/introducing-the-raspberry-pi-zero/video-outputs

Bye Jack

On Thursday, September 8, 2016 at 2:25:14 AM UTC-7, Jack wrote:
> Il giorno giovedì 8 settembre 2016 11:24:33 UTC+2, Jack ha scritto:
> 
> > > > Any suggestion?
> > > 
> > > Raspberry Pi 3.  We are using hdmi display, but there is a display port 
> > 
> > If he doesn't need WiFi, BT, or eth a Rpi Zero is definitely cheaper.
> > 
> > Bye Jack
> 
> For example:
> 
> https://learn.adafruit.com/introducing-the-raspberry-pi-zero/video-outputs
> 
> Bye Jack

Pi0 is $5, but shipping is probably $10.  Or you can buy $195 of accessories for free shipping, but pi0 is limit 1.

Elsewhere, pi0 goes for around $15 and pi3 for $35.

Perhaps we can ask this guy where he is moving from pi0 to pi3:

http://www.ebay.com/itm/Raspberry-Pi-Zero-Camera-V1-3-with-case-8gb-SD-card-wifi-USB-mini-USB-cable-/191947508204?hash=item2cb0f689ec:g:LaUAAOSwgZ1Xs0oS

On Thursday, September 8, 2016 at 9:06:14 AM UTC-7, edward....@gmail.com wrote:
> On Thursday, September 8, 2016 at 2:25:14 AM UTC-7, Jack wrote:
> > Il giorno giovedì 8 settembre 2016 11:24:33 UTC+2, Jack ha scritto:
> > 
> > > > > Any suggestion?
> > > > 
> > > > Raspberry Pi 3.  We are using hdmi display, but there is a display port 
> > > 
> > > If he doesn't need WiFi, BT, or eth a Rpi Zero is definitely cheaper.
> > > 
> > > Bye Jack
> > 
> > For example:
> > 
> > https://learn.adafruit.com/introducing-the-raspberry-pi-zero/video-outputs
> > 
> > Bye Jack
> 
> Pi0 is $5, but shipping is probably $10.  Or you can buy $195 of accessories for free shipping, but pi0 is limit 1.
> 
> Elsewhere, pi0 goes for around $15 and pi3 for $35.
> 
> Perhaps we can ask this guy where he is moving from pi0 to pi3:
                              (why)
> 
> http://www.ebay.com/itm/Raspberry-Pi-Zero-Camera-V1-3-with-case-8gb-SD-card-wifi-USB-mini-USB-cable-/191947508204?hash=item2cb0f689ec:g:LaUAAOSwgZ1Xs0oS

Il 08/09/2016 01:54, edward.ming.lee@gmail.com ha scritto:
 > On Wednesday, September 7, 2016 at 4:16:16 PM UTC-7, pozz wrote:
 >> I need to develop a product based on Linux embedded (because I need to
 >> communicate with a 4G modem through USB and I have the drivers for 
Linux)..
 >>
 >> So I'm searching an almost ready-to-use solution for this product (I
 >> should minimize design cost even if this increases the price of a single
 >> product... I will produce only 10-20 pieces at the moment).
 >>
 >> The system should have only a USB host port (for 4G modem) and a small
 >> (2.8-4.3") display TFT with resistive touch panel.
 >> The display should be mounted on a panel.
 >>
 >> The best would be to have a SOM solution, so I can design my simple and
 >> custom carrier board where to mount the SOM, the 4G modem, power supply
 >> and so on.
 >> However I could use a complete (with connector) board (I'll interface it
 >> with a my custom board).
 >>
 >> The most important thing: I don't want to waste too much time to make
 >> Linux and display running. I'd like to write only the final application.
 >> Linux and display should run from the beginning.
 >>
 >> The GUI will be very simple: only about 10 different screens with some
 >> settigs and status info.  No more.
 >>
 >> Any suggestion?
 >
 > Raspberry Pi 3.  We are using hdmi display,

I think it's very difficult to find a small display with HDMI connection.

 > but there is a display port on-board.

Do you mean the DSI (Display Serial Interface)?  Even in this case, I 
think it's very difficult to find a small TFT display with DSI port that 
can be purchased as a standard product.
If you have any suggestions where to find, please tell me.

I think the best method to interface a small (2.8-4.3") TFT display is 
using a display module with an integrated display controller (such as, 
ILI9341).  The display controller can be connected to the SPI link.

As here [https://www.adafruit.com/product/1601].



 > I am sure you can find an LCD screen for it.  We are using T-mobile USB
 > 4G modem, works fine with the network and modem manager.  The only
 > problem is that the USB modem would time-out when not in use for a
 > while, and only reboot can bring it back on line.  We might end up
 > using a network keep-alive connection to keep it up.

Sincerely, I only need to send some AT commands and receive answers.  I 
don't need to make a real IP connection.  So I only need a serial port 
to open.

Telit (the manufacturer of the 4G modem I'll use) says the USB of modem 
is a standard CDC ACM and the Linux driver should be already included 
(cdc_acm).
Do you know if cdc_acm is included in Raspberry Pi Linux kernel?
Have you tried to send AT commands to your modem?


 > We only need one USB host for normal op, but a second port is handy for
 > keyboard when we messed up the 4G or Wifi connections.
 > RPI has 4 USB ports.

pozz <pozzugno@gmail.com> writes:
> I think it's very difficult to find a small display with HDMI connection.

5 inch is easy to find--does yours have to be smaller?  Could you
consider using a small Android tablet or something similar?

> Do you know if cdc_acm is included in Raspberry Pi Linux kernel?
> Have you tried to send AT commands to your modem?

Don't know if it's in the raspberry pi kernel but Linux has supported it
forever, at least as a loadable module.  I've never used it myself though.

On Thursday, September 8, 2016 at 4:32:34 PM UTC-7, Paul Rubin wrote:
> pozz <pozzugno@gmail.com> writes:
> > I think it's very difficult to find a small display with HDMI connection.
> 
> 5 inch is easy to find--does yours have to be smaller?  Could you
> consider using a small Android tablet or something similar?

Tablet is not for embedded.  It's difficult set up default behaviors and hard to hook up I/Os.  I want my device to power up and connected, without any clicking or tapping.

> 
> > Do you know if cdc_acm is included in Raspberry Pi Linux kernel?
> > Have you tried to send AT commands to your modem?

The modem-manger does that.  I don't have to deal with the details.

> 
> Don't know if it's in the raspberry pi kernel but Linux has supported it
> forever, at least as a loadable module.  I've never used it myself though.

Yes, it's in there.  It recognize the USB modem, bring up an usb0 interface, use it as gateway, and reach the net.

In fact, i have both wlan0 and usb0 connected to the net.  Not sure how it decide which one to use.

Den fredag den 9. september 2016 kl. 02.15.49 UTC+2 skrev edward....@gmail.com:
> On Thursday, September 8, 2016 at 4:32:34 PM UTC-7, Paul Rubin wrote:
> > pozz <pozzugno@gmail.com> writes:
> > > I think it's very difficult to find a small display with HDMI connection.
> > 
> > 5 inch is easy to find--does yours have to be smaller?  Could you
> > consider using a small Android tablet or something similar?
> 
> Tablet is not for embedded.  It's difficult set up default behaviors and hard to hook up I/Os.  I want my device to power up and connected, without any clicking or tapping.
> 

I have a dirt cheap 7" tablet, it can run linux. It is a standard allwinner 
a10 cpu. No I/O though


-Lasse