Retroflag NESPi Case - Soft Power & Reset Hack

Yahmez

@throbinson In the 'ETA Prime' version the reset sends a signal to the Pi which then (through a script watching for the signal) initiates a shutdown. The power switch operates as it does in the original case simply hard cutting the power to the Pi.

Yahmez

@druz That's awesome man! I was originally going to go this route till I found the pololu boards and compared the cost VS the effort required.

THRobinson

@yahmez said in Retroflag NESPi Case - Soft Power & Reset Hack:

@throbinson Either one will work fine. There are distributors of pololu in canada... did you check if they have them?

Yup... none seem to have them that I could find. One seller was close, had a 2812,2813,2814,2815... but not the 2810 or 2811. :S

ETAPrime I think will work for me... safe shut down, and full power off, pretty much all I need.

I wonder, and sure it can be done... go the ETAPrime route and also add a 3rd button, very small momentary switch, just drill a hole in the case at the back or under the flap and attach to the GPIO as a reset button.

Mostly though just looking for a safe shutdown then full power off... I hope that I won't need to reset very often.

You said you were going this route before seeing cost-vs-effort... which route did you end up going?

Yahmez

@throbinson Regarding the cost VS effort comment, I was talking about what @druz did (freeforming the components) until I found the pololu board.

Keep in mind, if your looking to safely shut down as simply as possible, you can simply navigate to shutdown in the ES menu and after it completes the shutdown just hit the power button, no mod required for that.

Yahmez

@throbinson You could use this instead, it's overkill but in this case functionally equivalent to the smaller boards.
http://www.robotshop.com/en/45-40v-dc-8a-big-mosfet-slide-switch-reverse-voltage-protection.html

THRobinson

@yahmez I kinda wish I knew more about this stuff, because probably a lot of suitable boards. All I see is a small board with a switch on it. Had to Google was a mosfet was. :D

I'm still a bit confused on what this mod does... ETA Prime's, the reboot is a safe shutdown, can press again to start up as well, sorta a manual reboot. Power kills the power completely. So basically, hit reset, wait for it to shutdown safely, then press power and it's off. Hit power again, it all comes on.

For this one... manual says "When done, the hack allows you to safely shutdown (via the power button) and reset (via the reset button) your Raspberry Pi." which I was unclear about... so, reset sends a command to restart the system? or just the current game? Then power sends a safe shutdown command, and once safely shut down, it then shuts the power off completely? or shuts down then I have to yank the plug?

druz

@throbinson yep, that's pretty much what it does, no need to yank the plug. The whole idea is for the MOSFET to delay the power shut off until the pie has properly shutdown. One advantage of this is, it will prevent you (or someone who's not familiar of how the power/reset buttons work) from mistakenly pushing the power button before hitting the reset switch and waiting for the safe shutdown script to execute. This is a far safer and elegant solution.

Again, for anyone interested in building this without the ready made pololu switch board (The pololu board is actually a good idea, I just didn't want to wait for the board to arrive and I had all the components on my bench :P), I have drawn up a schematic of the simplified build.

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THRobinson

Gotcha... thanks.

Debating buying 20kits worth of parts to make it worthwhile for ship costs and just sell them on eBay (Canada only) at cost+ship... then make back my cost on shipping and save some money for my fellow Canucks.

Probably $8CAD for the full kit... if there's interest at all? As it is, the Pololu after shipping is about $20CAD, the kit may help some people out.

I believe the original poster had a kit online, found an old link, but doesn't seem to be selling anymore. @Yahmez If I put a few kits up on eBay, are you ok with me linking to your doc?

Yahmez

@throbinson Yes, I sold about 40 or so kits online but I completely underestimated the demand. I only put together the kits to help out a few online friends who had issues sourcing all the components, but I sold out in a few days. I decided against selling any more due to limited free time (I work full time and have four young kids). A few other people have been selling the kits since then, one guy made some custom pcbs to completely replace the stock switch PCB with all the parts for the safe shutdown mod. I am completely fine with you linking to my walk through, I shared it with the internets for anyone interested in trying it, not to make money.

THRobinson

@yahmez Cool... thanks. Didn't know that much of a demand. I'll only put a dozen up I think, just to make back the shipping costs. That's pretty cool about the guy who made a new board for it... may have to search for that.

I did see on eBay some people are selling the cases pre-modded. Can't recall how much more they were or what mod was done though.

mitu

@yahmez said in Retroflag NESPi Case - Soft Power & Reset Hack:

one guy made some custom pcbs to completely replace the stock switch PCB with all the parts for the safe shutdown mod

Is it this one - https://github.com/mafe72/Retroflag-NESPi-Front-Panel-Control-Board ?

Yahmez

@mitu I take it back. Two people have made pcbs. The one you linked does not include any mosfet switching capability it simply changes the function of the power and reset buttons into inputs for gpio.

Yahmez

@throbinson yes there are a couple of guys who mod the cases with my method and sell them on eBay.

xadox

@yahmez Thx for your great mod & guide.
I implemented your mod yesterday and it's working like charm.

Maybe you could also mention the ES gracefully Shutdown Mod in the starting post:
https://retropie.org.uk/forum/topic/12895/ensuring-es-gracefully-finish-and-save-metadata-in-every-system-shutdown

Yahmez

@xadox good idea. I'll do that.

Riverstorm

@yahmez said in Retroflag NESPi Case - Soft Power & Reset Hack:

@mitu I take it back. Two people have made pcbs. The one you linked does not include any mosfet switching capability it simply changes the function of the power and reset buttons into inputs for gpio.

Referring to that link without the mosfet switching you're still not fully powered down and the LED will still be lit?

I would also be interested in what @mitu was asking. You would happen to know if these guys are selling a pre-built replacement PCB or a link to it?

mitu

@riverstorm From the link I gave a few posts back, there's a link to https://oshpark.com/shared_projects/V2yqoyFn which seems to have an order page.

Riverstorm

@mitu said in Retroflag NESPi Case - Soft Power & Reset Hack:

@riverstorm From the link I gave a few posts back, there's a link to https://oshpark.com/shared_projects/V2yqoyFn which seems to have an order page.

Thanks Mitu for the link. Would this shut down safely like a complete power off/on without unplugging the unit? The instructions are short and it looks you need an account to get the pricing. It looks good though.

Yahmez

http://www.ncspecialties.com/computers/customcomputers/nespi/softshutdown/v2/

That's the one I was referring to.

mitu

@riverstorm The instructions are on the github design page, which I linked in the 1st post. It seems to run similar to all the other projects that use push buttons to trigger GPIO in/out, it has a script to map the actions to OS commands - shutdown/reset/fan control.