So I've just done some searching on the web, turns out you can get video out of 2000 and 3000 series PSPs, which I didn't know about (I've only ever had a 1000 series, and besides that I know little about the PSP). You'll need a PSP component cable, and some way to capture the component signal. Hope that that helps!
Yes! Do you have custom firmware on your PSP? If so, you can use a tool called RemoteJoy Lite to capture your PSP screen through USB cable. https://www.psx-place.com/resources/remote-joy-lite-0-20a.219/ Let me know if you need help setting that up, it can be a bit annoying if you're not familiar with this kinda stuff.
One thing to really keep in mind, is that it is highly likely that all loading screens on your PSP might be very long, compared to loading screens in emulator runs. DarkJarris and me have been thinking of ways to get around this and make runs fair, no matter if you're on actual PSP or an emulator, but we've not yet found anything. Just something to keep in mind :)
Thought it'd be a good idea to put this out on the board instead of just on Discord, to have a more clear oversight on what's being done to get loadtimes out of the equation.
So, the main reason this is a thing at all, is because, as it turns out, actual PSPs tend to not be consistent with loadtimes, versus the PPSSPP emulator (and probably others, if they even exist, I don't know). Since an Arcade 42 run contains a minimum of 84 loading screens, significant loadtimes create a significant disadvantage, and are thus not very fair.
One idea so far has been to manually time loadtimes separate from the splittimer with something like a stopwatch app, either live or after a run, but this is not preferable due to inaccuracies. This might, however, be the only (feasible) way to deduct loadtimes from past runs.
The ideal solution would be some cross-platform and automatic script that can trigger a split timer to pause or its own separate stopwatch to count while it detects a loading screen. If the script interacts with a split timer, it would be important to look into doing this for multiple split timers, as not every split timer works on all platforms; if the script has its own stopwatch, it'd be useful to include an input box for final run time to automatically calculate loadtime-deducted run time. I am personally thinking of ways to achieve this with my very limited coding experience, but I've not gotten very far yet.
I'm personally keeping myself from doing any live-timed runs before there's a good solution to this, to prevent having to do more manual stopwatching of loadtimes (plus so I can actually see right after the run what my final time is).