Running roms off a USB

Dominus · 29 Aug 2016, 23:29

I just have a quick question about running roms off a USB stick. Does it work as added memory or do all the roms need to run off the stick now? I don't want to go out and get a 16 GB usb stick if my SD is already 32 GB.

cyperghost · 30 Aug 2016, 08:57

@Dominus you decide!
Best way imho is just to link roms from USB to ROM via LN -s Commando

But there is also a nice wdritten wiki how to do. It might be a ggold idea to just link huge files (PSX or Dreamcast Roms) Form USB to ROMS folder.

Sorry I am writing from tablet with non english keyboard Chars.

dankcushions · 30 Aug 2016, 09:55

@Dominus the guide is to make it run all your roms. to split the storage (for example all PSX drives on the USB stick, everything else on the SD) is possible but it would make what is already a complex guide even more complex. plus i recommend separating roms from your install anyway.

also, you should buy a bigger USB since they are so cheap. with 32gb or 64gb you will probably be ok for most situations.

iconrumble · 30 Aug 2016, 10:06

you can use the usb the two ways. I personally have console roms on my sd card and have an usb stick for psx isos
My usb gets automounted on boot; I then added a symbolic link in the retropie roms folder linking the folder on the usb with the psx isos, using ln -s [target] [linkname].

Dominus · 31 Aug 2016, 06:05

@iconrumble Yeah that sounds like exactly what I want to do. I'd love to just put all my PSX games onto a USB stick, and leave the smaller console games on the SD. Do I follow the wiki somewhat then? What do I do after I disable the USB transfer daemon?

Dominus · 31 Aug 2016, 06:27

This video is a little old, but do I just want to do this basically? Or is there a better way to do it now?:

iconrumble · 31 Aug 2016, 07:39

@Dominus The video opts to ediit the file es_systems.cfg, to point emulationstation to the usb. The problem with that is that this cfg file can be overwritten when updating retropie.
I prefer to create a symbolic link ( https://en.wikipedia.org/wiki/Symbolic_link ) pointing to the usb. Retropie will still look for the rom on the sd card but will be redirected by this link to the usb.
To do this, create a "psx" folder on your usb, ssh into the pi, go to home/retropie/roms, delete the existing "psx" folder and enter sudo ln -s /media/usb0/psx psx This will create a link in your sdcard roms folder, named "psx", pointing to "psx" folder in your usb. First follow the video to find the correct path to your usb (usb0, usb1, etc).

Dominus · 4 Sept 2016, 22:09

I have yet to try this, but I am sure it will work so thank you in advance! But I had another question... are you able to split the roms for one system up onto 2 different USB Sticks?

iconrumble · 5 Sept 2016, 08:03

@Dominus instead of symlink the entire "psx" folder, you can keep the "psx" folder on the sd and create two symlinks inside that, each one for each usb.
Example:
go to home/retropie/roms/psx;
enter sudo ln -s /media/usb0/psx USB0 --> this creates the symlink for the fist usb
enter sudo ln -s /media/usb1/psx USB1 --> this creates the symlink for the second usb
don't forget to confirm the usb paths.

Dominus · 7 Sept 2016, 20:01

@iconrumble Thanks man! That is so much easier then what is explained in the wiki. I haven't tried the 2 usb Symbolic Link to same folder, but at least I know it is possible. Thanks!

Juakin · 9 Jul 2016, 22:17

@iconrumble said in Running roms off a USB:

you can use the usb the two ways. I personally have console roms on my sd card and have an usb stick for psx isos
My usb gets automounted on boot; I then added a symbolic link in the retropie roms folder linking the folder on the usb with the psx isos, using ln -s [target] [linkname].

Dude, this is exactly the way I want to configure my RetroPie, can you please explain (or give a link) on how to automount USB's on Retropie??
Also, if you place a PSX iso in /home/pi/RetroPie/roms/psx and at the same time have more of them in /media/usb0/roms/psx will load all of them, or you can only see the ones on the USB??

Dominus · 7 Sept 2016, 22:19

@iconrumble I never did no automounting, do I have to do that?!? It seems to have worked already?

Juakin · 7 Sept 2016, 23:52

@iconrumble nevermind I've already done it...
@Dominus I had to, my usb's didn't mount automatically when I connected them, In fact if I was on the desktop (lxde) and connect one of them it asked for a password, so yes, I had to edit the "fstab" file and add automount to my devices.

iconrumble · 8 Sept 2016, 07:55

@Juakin In my case, I swapped the psx folder on the sd card with a symlink, so I can only see isos on the usb. You could create the symlink inside the sd psx folder (just like a subfolder), that way you can put isos in the sd card and the usb.

@Dominus @Juakin My 64gb fat32 usb get's automounted at boot, I didn't have to edit the fstab or do anything else. I'm running of retropie 3.8 image updated to 4.0.1

Juakin · 8 Sept 2016, 11:31

@iconrumble said in Running roms off a USB:

@Juakin In my case, I swapped the psx folder on the sd card with a symlink, so I can only see isos on the usb. You could create the symlink inside the sd psx folder (just like a subfolder), that way you can put isos in the sd card and the usb.

That's exactly what I did, now I can load my ISOS from both places.
Thanks for the info.

AndersHP · 27 Oct 2016, 06:46

Wow, having just read this topic I'm getting convinced that even I can do this.

Does this generally slow down or in other ways stress the Retropie? And what are the exact benefits of running ROMs off a USB, if there's Space enough on the SD?

Apart from that, do you just use USB Sticks, or USB external harddives? Are there any min. requirements for the USB (read/write speed etc)?

What about Steven Selph's scraper. will this also understand the symlink and still scrape the games?

dankcushions · 27 Oct 2016, 09:12

@AndersHP said in Running roms off a USB:

Wow, having just read this topic I'm getting convinced that even I can do this.

Does this generally slow down or in other ways stress the Retropie?

no. USB transfer will probably be faster than SD cards (?), but in any case it doesn't really matter.

And what are the exact benefits of running ROMs off a USB, if there's Space enough on the SD?

the benefits are listed here: https://github.com/RetroPie/RetroPie-Setup/wiki/Running-ROMs-from-a-USB-drive

Apart from that, do you just use USB Sticks, or USB external harddives?

i use a USB stick. a harddrive seems excessive. that amount of ROMs would surely grind ES to a hault.

Are there any min. requirements for the USB (read/write speed etc)?

no.

What about Steven Selph's scraper. will this also understand the symlink and still scrape the games?

i don't use symlinks, i use the recommended mount method. i would have thought it would, though.

spannernick1 · 27 Oct 2016, 12:37

Edited... question already be asked.

Dominus · 27 Oct 2016, 22:10

@AndersHP @dankcushions
I find that save states take a hell of a long time to save! I have PSX and GBA on my USB stick, and I bet it takes 10 seconds or more to save PSX games (loading is pretty instant it seems), and GBA about 5 seconds? Just looking into why that is (could be my USB stick?) or to move the save states to the SD card.

dankcushions · 27 Oct 2016, 23:24

@Dominus said in Running roms off a USB:

@AndersHP @dankcushions
I find that save states take a hell of a long time to save! I have PSX and GBA on my USB stick, and I bet it takes 10 seconds or more to save PSX games (loading is pretty instant it seems), and GBA about 5 seconds? Just looking into why that is (could be my USB stick?) or to move the save states to the SD card.

it may just be the emulation. the original psx memory cards were slow, so the games / bios may have no idea they are being run on much better hardware. it's the same reason load times still exist for psx games, despite running on machines that could hold the whole ISO in memory.