This forum uses cookies
This forum makes use of cookies to store your login information if you are registered, and your last visit if you are not. Cookies are small text documents stored on your computer; the cookies set by this forum can only be used on this website and pose no security risk. Cookies on this forum also track the specific topics you have read and when you last read them. Please confirm whether you accept or reject these cookies being set.

A cookie will be stored in your browser regardless of choice to prevent you being asked this question again. You will be able to change your cookie settings at any time using the link in the footer.

Thread Rating:
  • 1 Vote(s) - 5 Average
  • 1
  • 2
  • 3
  • 4
  • 5
7" REMOTE WATERPROOF DISPLAY
#11
(2021-03-05, 10:09 PM)SARASTRO Wrote:
(2021-03-05, 12:58 PM)affinite Wrote:
(2021-02-25, 08:18 AM)SARASTRO Wrote:
(2021-02-24, 10:41 PM)rastam4n Wrote: what was the cost of the screen?
194 USD plus freight (51 USD to Spain). I paid via PAYPAL

(2021-02-25, 01:24 AM)Techstyle Wrote: That's Awesome - thanks for Sharing!

with regard to Power, I found that I didn't trust other boat users to not turn the power off at the switches accidently so I added some simple electronics to my Pi to make the schematic below:


with this the switched power is connected to the breaker panel and the const 12V is connected to battery, if the switched voltage goes off it is sensed at pin 40 and a power down is started, once the Pi shuts down, the relay is turned off, disconnecting the constant 12V.  the hardware costs less than $10 and looks like the below: 


By connecting a momentary switch between pin 40 and ground, you can also start the shutdown process when pressed
A foolproof solution!
Thanks for the idea

Daylight viewing is OK ?
Good enough, even at 45% from vertical and under high sun. (better if installed vertically)
But it has a certain "mirror" effect. I placed this question to Shiovision, and I was told that the capacitive touchscreen is better in this aspect. (mine is restive touchscreen)

Thanks for the feedback. I mounted my cockpit display under the sprayhood so not in direct sunlight. This display looks like a good option when time comes to replace the rugged Panasonic tablet I have now
Reply
#12
(2021-02-25, 01:24 AM)Techstyle Wrote: That's Awesome - thanks for Sharing!

with regard to Power, I found that I didn't trust other boat users to not turn the power off at the switches accidently so I added some simple electronics to my Pi to make the schematic below:


with this the switched power is connected to the breaker panel and the const 12V is connected to battery, if the switched voltage goes off it is sensed at pin 40 and a power down is started, once the Pi shuts down, the relay is turned off, disconnecting the constant 12V.  the hardware costs less than $10 and looks like the below: 


By connecting a momentary switch between pin 40 and ground, you can also start the shutdown process when pressed
I find the idea very interesting , and I want to test it using a EDLC capacitor instead of a second permanent supply line. (to avoid the additional wirings from de battery to the navpod)
I supuse that the resistance is placed to produce a minimum current drain from the 3,3v supply. Is this?. What is the value you use for that?
Thanks for your help
Reply
#13
(2021-03-11, 07:33 PM)SARASTRO Wrote:
(2021-02-25, 01:24 AM)Techstyle Wrote: That's Awesome - thanks for Sharing!

with regard to Power, I found that I didn't trust other boat users to not turn the power off at the switches accidently so I added some simple electronics to my Pi to make the schematic below:


with this the switched power is connected to the breaker panel and the const 12V is connected to battery, if the switched voltage goes off it is sensed at pin 40 and a power down is started, once the Pi shuts down, the relay is turned off, disconnecting the constant 12V.  the hardware costs less than $10 and looks like the below: 


By connecting a momentary switch between pin 40 and ground, you can also start the shutdown process when pressed
I find the idea very interesting , and I want to test it using a EDLC capacitor instead of a second permanent supply line. (to avoid the additional wirings from de battery to the navpod)
I supuse that the resistance is placed to produce a minimum current drain from the 3,3v supply. Is this?. What is the value you use for that?
Thanks for your help
The resistor does 2 things - first, like you said, provides a minimum current draw and secondly, it brings the voltage down quickly when power is cut so the shutdown signal is fast. 

I believe it is a 1K resistor. 

Please keep me updated with how you get on with the capacitor. It would be good to understand what peripherals you have connected.
Reply
#14
(2021-03-14, 12:15 AM)Techstyle Wrote:
(2021-03-11, 07:33 PM)SARASTRO Wrote:
(2021-02-25, 01:24 AM)Techstyle Wrote: That's Awesome - thanks for Sharing!

with regard to Power, I found that I didn't trust other boat users to not turn the power off at the switches accidently so I added some simple electronics to my Pi to make the schematic below:


with this the switched power is connected to the breaker panel and the const 12V is connected to battery, if the switched voltage goes off it is sensed at pin 40 and a power down is started, once the Pi shuts down, the relay is turned off, disconnecting the constant 12V.  the hardware costs less than $10 and looks like the below: 


By connecting a momentary switch between pin 40 and ground, you can also start the shutdown process when pressed
I find the idea very interesting , and I want to test it using a EDLC capacitor instead of a second permanent supply line. (to avoid the additional wirings from de battery to the navpod)
I supuse that the resistance is placed to produce a minimum current drain from the 3,3v supply. Is this?. What is the value you use for that?
Thanks for your help
The resistor does 2 things - first, like you said, provides a minimum current draw and secondly, it brings the voltage down quickly when power is cut so the shutdown signal is fast. 

I believe it is a 1K resistor. 

Please keep me updated with how you get on with the capacitor. It would be good to understand what peripherals you have connected.

I will update progress as soon as I receive the components and make some trials.Meanwhile; make some theoretical calculations about the issue
Reply
#15
I place here the progress of this issue. 
I got from Aliexpress a super-capacitor boost pack of 2 Farad capacity at 16V. My own conservative calculations determined a theoretical 1,6 F charging at 12V.
This pack is very compact (65 x 35 mm) and cheaper that a LiPo pack.  (Less than 8 euro)
Tested feeding a 12 to 5 V buck converted, can hold the Pi alive during a complete cycle of start up and shutdown on a Pi 3B + 5" display. (Much more if the display has independent supply line, as in my 7" waterproof display)

No need of any control electronic for the charge of super capacitor bank (Has his own balancing circuit to avoid exceeding 2,7V on any condenser). 
Simply; the condenser are charged in seconds when connected to the ship's battery.

The circuit to protect the Pi in case of power-off, is divided in two parts:
A battery voltage detector: with an operational amplifier (CA3130) that compares the battery voltage (divided by 2) with a reference 5,1V created with a zener diode. When system is switched off, the op-amp turns output on, and activates a reed relay (R1).

A pulse generator to shortcut GPIO3 to GND (pins 5 and 6 on Rpi): When battery supply is working, a electrolytic capacitor is charged to 12V, and can't be discharged back because there is a diode blocking reverse way. When R1 is activated, the capacitor discharges through a voltaje reducer to 5V (7805) and activates reed relay R2. This relay is ON during the lapse of time needed to discharge the capacitor from 12V to aprox. 6,5V, and returns OFF. During this time, the contacto shorts GPIO3 to GND, forcing de Pi to shutdown, while the super capacitors are maintaining the supply during the time needed.

Of course; in this project I do not need to use I2C comms. so I can use GPIO 3 for that purpose. Also, I install, in parallel, a manual Pushbutton that allows to shutdown and re-start pi without power-off.

With that solution; the 7" display can be switched on / off from a common switch jointly with all other "navigation instruments" without problems. This is a must if your co-skipper only use the Battery that disconnects service battery in the ship.

Next development can be a more complete solution for using GPIO17 and 3V3 signal to control the primary RPi (I shall start a new thread for that)

Sorry; two pictures were incomplete

Last picture

Complete diagram


Attached Files Image(s)
                               
Reply
#16
(2021-04-01, 09:45 AM)SARASTRO Wrote: I place here the progress of this issue. 
I got from Aliexpress a super-capacitor boost pack of 2 Farad capacity at 16V. My own conservative calculations determined a theoretical 1,6 F charging at 12V.
This pack is very compact (65 x 35 mm) and cheaper that a LiPo pack.  (Less than 8 euro)
Tested feeding a 12 to 5 V buck converted, can hold the Pi alive during a complete cycle of start up and shutdown on a Pi 3B + 5" display. (Much more if the display has independent supply line, as in my 7" waterproof display)

No need of any control electronic for the charge of super capacitor bank (Has his own balancing circuit to avoid exceeding 2,7V on any condenser). 
Simply; the condenser are charged in seconds when connected to the ship's battery.

The circuit to protect the Pi in case of power-off, is divided in two parts:
A battery voltage detector: with an operational amplifier (CA3130) that compares the battery voltage (divided by 2) with a reference 5,1V created with a zener diode. When system is switched off, the op-amp turns output on, and activates a reed relay (R1).

A pulse generator to shortcut GPIO3 to GND (pins 5 and 6 on Rpi): When battery supply is working, a electrolytic capacitor is charged to 12V, and can't be discharged back because there is a diode blocking reverse way. When R1 is activated, the capacitor discharges through a voltaje reducer to 5V (7805) and activates reed relay R2. This relay is ON during the lapse of time needed to discharge the capacitor from 12V to aprox. 6,5V, and returns OFF. During this time, the contacto shorts GPIO3 to GND, forcing de Pi to shutdown, while the super capacitors are maintaining the supply during the time needed.

Of course; in this project I do not need to use I2C comms. so I can use GPIO 3 for that purpose. Also, I install, in parallel, a manual Pushbutton that allows to shutdown and re-start pi without power-off.

With that solution; the 7" display can be switched on / off from a common switch jointly with all other "navigation instruments" without problems. This is a must if your co-skipper only use the Battery that disconnects service battery in the ship.

Next development can be a more complete solution for using GPIO17 and 3V3 signal to control the primary RPi (I shall start a new thread for that)

Sorry; two pictures were incomplete

Last picture

Complete diagram

Nice set up on a boat!
I've been testing BBN OS image with Sinhovision screen.
I didn't find OpenPlotter being user friendly on touchscreen.
You might give a try to https://github.com/bareboat-necessities/lysmarine_gen
armhf version with 64-bit kernel.

Getting Started Guide is here https://bareboat-necessities.github.io/m...at-os.html

Thanks,
--MG
Download BBN Marine OS for raspberry pi 

https://bareboat-necessities.github.io/m...at-os.html

Video of actual installation:

https://www.youtube.com/watch?v=3zMjUs2X3qU


Reply
#17
(2021-04-01, 09:45 AM)SARASTRO Wrote: I place here the progress of this issue. 
I got from Aliexpress a super-capacitor boost pack of 2 Farad capacity at 16V. My own conservative calculations determined a theoretical 1,6 F charging at 12V.
This pack is very compact (65 x 35 mm) and cheaper that a LiPo pack.  (Less than 8 euro)
Tested feeding a 12 to 5 V buck converted, can hold the Pi alive during a complete cycle of start up and shutdown on a Pi 3B + 5" display. (Much more if the display has independent supply line, as in my 7" waterproof display)

No need of any control electronic for the charge of super capacitor bank (Has his own balancing circuit to avoid exceeding 2,7V on any condenser). 
Simply; the condenser are charged in seconds when connected to the ship's battery.

The circuit to protect the Pi in case of power-off, is divided in two parts:
A battery voltage detector: with an operational amplifier (CA3130) that compares the battery voltage (divided by 2) with a reference 5,1V created with a zener diode. When system is switched off, the op-amp turns output on, and activates a reed relay (R1).

A pulse generator to shortcut GPIO3 to GND (pins 5 and 6 on Rpi): When battery supply is working, a electrolytic capacitor is charged to 12V, and can't be discharged back because there is a diode blocking reverse way. When R1 is activated, the capacitor discharges through a voltaje reducer to 5V (7805) and activates reed relay R2. This relay is ON during the lapse of time needed to discharge the capacitor from 12V to aprox. 6,5V, and returns OFF. During this time, the contacto shorts GPIO3 to GND, forcing de Pi to shutdown, while the super capacitors are maintaining the supply during the time needed.

Of course; in this project I do not need to use I2C comms. so I can use GPIO 3 for that purpose. Also, I install, in parallel, a manual Pushbutton that allows to shutdown and re-start pi without power-off.

With that solution; the 7" display can be switched on / off from a common switch jointly with all other "navigation instruments" without problems. This is a must if your co-skipper only use the Battery that disconnects service battery in the ship.

Next development can be a more complete solution for using GPIO17 and 3V3 signal to control the primary RPi (I shall start a new thread for that)

Sorry; two pictures were incomplete

Last picture

Complete diagram

Thank you so much for sharing the solution and especially the photos of the capacitor boost pack.
Reply
#18
[attachment=1445 Wrote:T3chfr3ak72! pid='18895' dateline='1617751911']
(2021-04-01, 09:45 AM)SARASTRO Wrote: I place here the progress of this issue. 
I got from Aliexpress a super-capacitor boost pack of 2 Farad capacity at 16V. My own conservative calculations determined a theoretical 1,6 F charging at 12V.
This pack is very compact (65 x 35 mm) and cheaper that a LiPo pack.  (Less than 8 euro)
Tested feeding a 12 to 5 V buck converted, can hold the Pi alive during a complete cycle of start up and shutdown on a Pi 3B + 5" display. (Much more if the display has independent supply line, as in my 7" waterproof display)

No need of any control electronic for the charge of super capacitor bank (Has his own balancing circuit to avoid exceeding 2,7V on any condenser). 
Simply; the condenser are charged in seconds when connected to the ship's battery.

The circuit to protect the Pi in case of power-off, is divided in two parts:
A battery voltage detector: with an operational amplifier (CA3130) that compares the battery voltage (divided by 2) with a reference 5,1V created with a zener diode. When system is switched off, the op-amp turns output on, and activates a reed relay (R1).

A pulse generator to shortcut GPIO3 to GND (pins 5 and 6 on Rpi): When battery supply is working, a electrolytic capacitor is charged to 12V, and can't be discharged back because there is a diode blocking reverse way. When R1 is activated, the capacitor discharges through a voltaje reducer to 5V (7805) and activates reed relay R2. This relay is ON during the lapse of time needed to discharge the capacitor from 12V to aprox. 6,5V, and returns OFF. During this time, the contacto shorts GPIO3 to GND, forcing de Pi to shutdown, while the super capacitors are maintaining the supply during the time needed.

Of course; in this project I do not need to use I2C comms. so I can use GPIO 3 for that purpose. Also, I install, in parallel, a manual Pushbutton that allows to shutdown and re-start pi without power-off.

With that solution; the 7" display can be switched on / off from a common switch jointly with all other "navigation instruments" without problems. This is a must if your co-skipper only use the Battery that disconnects service battery in the ship.

Next development can be a more complete solution for using GPIO17 and 3V3 signal to control the primary RPi (I shall start a new thread for that)

Sorry; two pictures were incomplete

Last picture

Complete diagram

Thank you so much for sharing the solution and especially the photos of the capacitor boost pack.

There is a complete document for the project, in two parts

[attachment=1446 Wrote:SARASTRO pid='18967' dateline='1618072360']
(2021-04-07, 12:31 AM)T3chfr3ak72! Wrote:
(2021-04-01, 09:45 AM)SARASTRO Wrote: I place here the progress of this issue. 
I got from Aliexpress a super-capacitor boost pack of 2 Farad capacity at 16V. My own conservative calculations determined a theoretical 1,6 F charging at 12V.
This pack is very compact (65 x 35 mm) and cheaper that a LiPo pack.  (Less than 8 euro)
Tested feeding a 12 to 5 V buck converted, can hold the Pi alive during a complete cycle of start up and shutdown on a Pi 3B + 5" display. (Much more if the display has independent supply line, as in my 7" waterproof display)

No need of any control electronic for the charge of super capacitor bank (Has his own balancing circuit to avoid exceeding 2,7V on any condenser). 
Simply; the condenser are charged in seconds when connected to the ship's battery.

The circuit to protect the Pi in case of power-off, is divided in two parts:
A battery voltage detector: with an operational amplifier (CA3130) that compares the battery voltage (divided by 2) with a reference 5,1V created with a zener diode. When system is switched off, the op-amp turns output on, and activates a reed relay (R1).

A pulse generator to shortcut GPIO3 to GND (pins 5 and 6 on Rpi): When battery supply is working, a electrolytic capacitor is charged to 12V, and can't be discharged back because there is a diode blocking reverse way. When R1 is activated, the capacitor discharges through a voltaje reducer to 5V (7805) and activates reed relay R2. This relay is ON during the lapse of time needed to discharge the capacitor from 12V to aprox. 6,5V, and returns OFF. During this time, the contacto shorts GPIO3 to GND, forcing de Pi to shutdown, while the super capacitors are maintaining the supply during the time needed.

Of course; in this project I do not need to use I2C comms. so I can use GPIO 3 for that purpose. Also, I install, in parallel, a manual Pushbutton that allows to shutdown and re-start pi without power-off.

With that solution; the 7" display can be switched on / off from a common switch jointly with all other "navigation instruments" without problems. This is a must if your co-skipper only use the Battery that disconnects service battery in the ship.

Next development can be a more complete solution for using GPIO17 and 3V3 signal to control the primary RPi (I shall start a new thread for that)

Sorry; two pictures were incomplete

Last picture

Complete diagram

Thank you so much for sharing the solution and especially the photos of the capacitor boost pack.

There is a complete document for the project, in two parts

And second part


Attached Files
.pdf   7%22 DISPLAY PROJECT PART#1.pdf (Size: 1.22 MB / Downloads: 318)
.pdf   7%22 DISPLAY PART#2.pdf (Size: 880.78 KB / Downloads: 296)
Reply
#19
(2021-02-25, 01:24 AM)Techstyle Wrote: That's Awesome - thanks for Sharing!

with regard to Power, I found that I didn't trust other boat users to not turn the power off at the switches accidently so I added some simple electronics to my Pi to make the schematic below:


with this the switched power is connected to the breaker panel and the const 12V is connected to battery, if the switched voltage goes off it is sensed at pin 40 and a power down is started, once the Pi shuts down, the relay is turned off, disconnecting the constant 12V.  the hardware costs less than $10 and looks like the below: 


By connecting a momentary switch between pin 40 and ground, you can also start the shutdown process when pressed

@Techstyle: That sounds great. Could you please elaborate on the relay board, or maybe provide an ebay link?

Best regards, Tobias
Reply
#20
(2022-01-03, 02:55 PM)tobias.e Wrote:
(2021-02-25, 01:24 AM)Techstyle Wrote: That's Awesome - thanks for Sharing!

with regard to Power, I found that I didn't trust other boat users to not turn the power off at the switches accidently so I added some simple electronics to my Pi to make the schematic below:


with this the switched power is connected to the breaker panel and the const 12V is connected to battery, if the switched voltage goes off it is sensed at pin 40 and a power down is started, once the Pi shuts down, the relay is turned off, disconnecting the constant 12V.  the hardware costs less than $10 and looks like the below: 


By connecting a momentary switch between pin 40 and ground, you can also start the shutdown process when pressed

@Techstyle: That sounds great. Could you please elaborate on the relay board, or maybe provide an ebay link?

Best regards, Tobias

the relay board is: https://www.amazon.com/gp/product/B00LW15A4W

I have been using this successfully for all of the 2021 sailing season and it works great.  I do have the following lines of code in the config.txt:

Code:
dtoverlay=gpio-shutdown,gpio_pin=21,gpio_pull="down",active_low=1
gpio=20=op,dh
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)