sudomod

Posted: **Tue Feb 19, 2019 8:45 pm**

I'm working on a custom GBZ build. I'll be machining the housing from billet aluminum. I'm designing it from scratch so once it's off the CNC machine, all the parts should drop in. I have no problem with the mechanical side of things but I'm pulling my hair out trying to get the electrical side figured out.

My main problem right now is figuring out the power switch. I'm wanting to use a momentary push button instead of the slide switch. I don't want my kids to be sliding a power switch back and forth a 100 times, so in order to power the unit on and off, you will need to hold the power switch button for 5 seconds. After 5 seconds, I need to latch the EN HIGH of the Power Boost 1000c. In order to power the unit off, hold the power switch for 5 seconds and then have something that sends a signal to the PI GPIO to shut down with a script. Once shut down, latch EN LOW on the Power Boost.

So far I've been looking at the following to latch the EN...NPN/PNP combination, SCR Thyristor, and the 555 IC. I read somewhere that the 555 can be power hungry so it may not be the best choice for a battery powered device, there is a LMC555 but still may not be the best choice. When the unit is off, I would like to have all power consumption off. Seems like a 555 setup I saw, it would still draw a very small amount of current when the unit is off. I'm thinking a NPN/PNP combination might be the best option but I'm not sure how to go about adding the 5 second delay for both powering on and powering off.

Thanks in advance for your help. Looking forward to sharing my build on here.
Justin

Posted: **Wed Feb 20, 2019 1:05 am**

I would recommend Camble safe shutdown switch....

It turns the system on and off safely

https://sudomod.com/forum/viewtopic.php?f=38&t=2260

I don’t how old your kids are....

But two of my younger children are 3 & 5 yrs old who have played with builds I’ve made....

You’d be really surprised
Turning the system on/off 100 times won’t even factor into it (especially because where the switch is positioned)

They’ll be more into
playing the games
Or just holding the build and watching what’s on the screen...
In regards to the power switch, it’s if they actually remember (or can be bothered) to turn it off...

Even by the age of 4 they’ll have a reasonable understanding of what a on/off switch is about...
And use it responsibly (if they remember to use it)

Anything younger...
There just looking at the screen (bash buttons)
Anything older
And you shouldn’t even be worrying about anything like that

There are momentary button options out there...
(Google RPi safeshutdown)
But nothing that’s gonna give you a 5sec delay on either starting up or shutting down

Have more faith in your kids...
Their of a generation that’s a lot more tech savvy then us...

NB:
Not giving you a parenting class....
Just sharing my experience...
Especially as I don’t test my builds...
my kids do...

.

Posted: **Wed Feb 20, 2019 6:04 am**

VeteranGamer: Thanks for the reply. I actually bought one of Camble's switches the other day. It hasn't arrived yet. I do agree about kids probably being more interested in the games than messing with the power switch but I guess another reason for wanting a "hold 5 seconds" is so it doesn't accidentally turn on or off if I have it in a bag or something. After finishing my last bartop build (see attached image), my 3 and 5 year olds loved playing the games, but during the load screens they would flick the toggle switches. Of course these switches are pretty inviting to be flicked in the position they are in, so I was just thinking of curing this problem on the front end since it would be harder to add this switch mod later to an aluminum case. I'll do some more digging to see what I can come up with. VeteranGamer, your builds are great. Your's along with other great builds on here have given me the inspiration to start this project.

Posted: **Wed Feb 20, 2019 2:52 pm**

jwh02017 wrote: ↑
Tue Feb 19, 2019 8:45 pm
I'm working on a custom GBZ build. I'll be machining the housing from billet aluminum. I'm designing it from scratch so once it's off the CNC machine, all the parts should drop in. I have no problem with the mechanical side of things but I'm pulling my hair out trying to get the electrical side figured out.

My main problem right now is figuring out the power switch. I'm wanting to use a momentary push button instead of the slide switch. I don't want my kids to be sliding a power switch back and forth a 100 times, so in order to power the unit on and off, you will need to hold the power switch button for 5 seconds. After 5 seconds, I need to latch the EN HIGH of the Power Boost 1000c. In order to power the unit off, hold the power switch for 5 seconds and then have something that sends a signal to the PI GPIO to shut down with a script. Once shut down, latch EN LOW on the Power Boost.

So far I've been looking at the following to latch the EN...NPN/PNP combination, SCR Thyristor, and the 555 IC. I read somewhere that the 555 can be power hungry so it may not be the best choice for a battery powered device, there is a LMC555 but still may not be the best choice. When the unit is off, I would like to have all power consumption off. Seems like a 555 setup I saw, it would still draw a very small amount of current when the unit is off. I'm thinking a NPN/PNP combination might be the best option but I'm not sure how to go about adding the 5 second delay for both powering on and powering off.

Thanks in advance for your help. Looking forward to sharing my build on here.
Justin

May sound dumb, but why not leave the slide switch in for show, and have the real power switch in the battery compartment if its a big concern.

Posted: **Wed Feb 20, 2019 3:08 pm**

May sound dumb, but why not leave the slide switch in for show, and have the real power switch in the battery compartment if its a big concern.

I'm not making an exact copy of the Gameboy DMG-01 but it will look very similar to the average person. There are some features that I'm wanting and the only way I've found to do them is to make slight changes to the housing design/layout. By doing this, I've done away with the battery compartment and game slot. There will be 2 halves and they will be screwed together so I won't have access to the inside without a tool. Another "kid friendly" feature...haha

From what I've been reading, I believe a resistor and capacitor combination can be used to get the 5 second delay. Then once the capacitor is charged, it can send a high signal to a latching circuit, this will in turn enable the EN pin on the power boost. Now to just figure out how to unlatch it with the same power button after the PI has shutdown.

I know I'm probably making this project more complicated than what it has to be, but I like the learning process.

sudomod

Momentary power switch question

Momentary power switch question

Re: Momentary power switch question

Re: Momentary power switch question

Re: Momentary power switch question

Re: Momentary power switch question