Running homebrew emu's at 333mhz MAY have killed my PSP

laxer3a · Post by **laxer3a** » Sat Jun 18, 2005 2:20 am

To be honest, I would rather see people use lower clockrates (or lowest possible for each software) and learn how to better optimize their code.

Hum... Running a snes at full speed with copro on a 333 mhz is a challenge I think. (sound stereo 48 Khz :-P, no frame skip)

Try to emulate the ARM cpu at 16.7 Mhz on a PSP ?(GBA.. GBA.. GBA...)
Even with a good JIT its a challenge also.

So, thats not because we are bad coder that we want more power.
Its because we are GOOD coder that we want more power...
(sorry for the modesty here)

Don't think these boards are full of lamers that are wasting CPU to do useless empty while loop.
But respect the people because many of us here are probably able to do a good usage of each cycle available around here.(including you)

So I wouldn't mind if too high clockrates damage the PSP ;)

I feel really sad to read this. :-(

0xdeadface · Post by **0xdeadface** » Sat Jun 18, 2005 2:29 am

Bit offtopic but:

"Try to emulate the ARM cpu at 16.7 Mhz on a PSP ?(GBA.. GBA.. GBA...)
Even with a good JIT its a challenge also. "

I think the challenge wouldn't be to emulate it, but to detect what areas of code can be run as is, after all you're emulating on a similar architecture (processorwise) or through HLE. In that regard it's almost more feasible to run GBA code at high speed than SNES code.

Regarding the SNES and other emulators....I don't know about the currect GNU compilers, but I do know that the PSX devkit back then (also GNU) had a very lousy C compiler which produced code that was heavily optimizable when resorting to assembly.

0xdf

Agoln · Post by **Agoln** » Sat Jun 18, 2005 5:27 am

Can you only change the clock-speed on application-by-application basis? Or can you set it to let's say... 133 and it will stay there until you set it back to 222.

People are thinking "WHY would you EVER want to underclock it for non-testing purposes?" well... for a simple reason of video watching or even MP3 playing. There is no need for a 222 or even higher to watch movies / play music, and that way instead of like... 3-5 hours of battery life, you can get much more (I'm unsure of how much more, but a lot :P).

ector · Post by **ector** » Sat Jun 18, 2005 6:28 am

0xdeadface wrote:Bit offtopic but:

"Try to emulate the ARM cpu at 16.7 Mhz on a PSP ?(GBA.. GBA.. GBA...)
Even with a good JIT its a challenge also. "

I think the challenge wouldn't be to emulate it, but to detect what areas of code can be run as is, after all you're emulating on a similar architecture (processorwise) or through HLE. In that regard it's almost more feasible to run GBA code at high speed than SNES code.

Huh? GBA has an ARM and PSP has a MIPS. Huge difference there.. ARM on MIPS has to be one of the more difficult combinations to get really fast because of MIPS' total lack of flags vs the ARM's x86-like flags.

0xdeadface · Post by **0xdeadface** » Sat Jun 18, 2005 6:32 am

Crap, the horrible part is you're right,,and I'm not sure why I have always walked around thinking they were the same....

....Which kinda blows given that I coded mips assembly as a job.

I obviously never coded for the GBA.

:o\

0xdf

allthatinny · Post by **allthatinny** » Sat Jun 18, 2005 11:00 am

dude to be honest, seems like you fry your PSP because before the PSP runs out of Battary the screen turns gray with a little battery indicator blinking, then shuts off.

kemical · Post by **kemical** » Sun Jun 19, 2005 2:15 pm

sorry if i've started making people paranoid about running stuff at 333mhz, I still haven't been able to get my PSP working, thank you to everyone who's suggested things to try.
Right now I'm taking apart the PSP to see about the internal battery.

Maybe it wasn't related to the overclocking thing, It seems like it did the low battery behavior, the power light was flashing, the emulator locked up, and I was unable to power off the PSP from what I remember, I actually was about to pull the battery out because it made me get worried, and I think it then shut off by itself before I got the battery cover off.

Alcahest · Post by **Alcahest** » Sun Jun 19, 2005 3:04 pm

have you tried the following:
-Put battery inside PSP, connect AC adapter, then hold the power switch for 30 to 40 seconds. It will soft reset it.
Then release the Power switch, and then push the power switch one last time to put it ON.
Any results with this method?
Later,

Alcahest

DrEggman · Post by **DrEggman** » Sun Jun 19, 2005 3:52 pm

I had 2-3 cases where my PSP wouldnt respond to powering up. I would hit the power switch, but the green power light would just flick on for a brief second. My psp was pretty dead. Took the battery out, didnt fix it. Hooked up AC, didnt fix it. But I took the battery out and held the power switch for 15 seconds without AC hooked up. Worked. Had this happen again so I did the same thing, worked again. Try it.

zigzag · Post by **zigzag** » Wed Jun 22, 2005 2:24 pm

It could easily run more than full speed if it was using proper APIs and hardware graphics routines.

Darkcreator · Post by **Darkcreator** » Thu Jun 23, 2005 12:30 pm

kemical wrote:sorry if i've started making people paranoid about running stuff at 333mhz, I still haven't been able to get my PSP working, thank you to everyone who's suggested things to try.
Right now I'm taking apart the PSP to see about the internal battery.

Maybe it wasn't related to the overclocking thing, It seems like it did the low battery behavior, the power light was flashing, the emulator locked up, and I was unable to power off the PSP from what I remember, I actually was about to pull the battery out because it made me get worried, and I think it then shut off by itself before I got the battery cover off.

If one of your friends has a psp take his battery out and put it in your psp who knows you might have just killed your battery

tomt · Post by **tomt** » Fri Jun 24, 2005 7:54 pm

sorry bit O.T but does this mean if your psp goes into sleep mode whilst running homebrew it bricks it? has anyone tested whether there is a reliable way to fix this that will always work?

seems a bit dangerous running homebrew if its going to kill your psp if you let the battery get low

Guest · Post by **Guest** » Fri Jun 24, 2005 8:26 pm

I get the feeling that there are sleep modes and homebrew does not yet know how to handle them, especially in battery low situations.

It seems that people also do not know the difference between putting the psp into sleep mode and into "off" mode using the "power" switch.

tomt · Post by **tomt** » Fri Jun 24, 2005 10:21 pm

it seems strange that it should need to interact with the game/homebrew to go into sleep mode at all though unless it has some strange way of doing it

razorrifh · Post by **razorrifh** » Sat Jun 25, 2005 12:16 am

i doubt its anything strange. i would assume it would be a callback function from the firmware letting the game know to shutdown things (like telling it to pause basically) and that the machine is going to sleep for a while. its not like windows (and any other os?) that writes ram to a memory device in order to resume at a later time. it would work like that if it had onboard memory, and reserved space for that, but since there potentially might be noowhere to save that data to, and because its probably much much much faster to just keep everything in the memory where it is, and turn off the screen and other non-vital functions and probably turn the processor down to 33mhz or so (or less probably... its just gotta wait for the press of a button) it makes sence to me.

cyberheater · Post by **cyberheater** » Sun Jun 26, 2005 4:38 am

Same thing happen to me and a friend.

We have not been running homebrew but we did allow our PSPs to run down for a fair bit of time.

Here are my symptoms:-

For some reason they do not seem to be charging when I plug my PSP into the charger.

The orange charging light comes on for a short while then it stops.

When I check the status of the battery in the menu it states:-

Charge level 0%
Hours left -
Power Source External
Bettery Status Charged

If i replace the battery while the charger unit is in place:-

* The orange charge light comes on (for around 5 mins)

The battery status is:-

Charge level 0%
Hours left -
Power Source External
Battery Status Charging

But the battery never seems to charge.

Are your symptoms the same...

zigzag · Post by **zigzag** » Sun Jun 26, 2005 8:22 am

Are your symptoms the same...

No... his PSP is dead...

lshian · Post by **lshian** » Sun Jun 26, 2005 11:23 pm

DrEggman
I had 2-3 cases where my PSP wouldnt respond to powering up. I would hit the power switch, but the green power light would just flick on for a brief second. My psp was pretty dead. Took the battery out, didnt fix it. Hooked up AC, didnt fix it. But I took the battery out and held the power switch for 15 seconds without AC hooked up. Worked. Had this happen again so I did the same thing, worked again. Try it.

Ya I got this cases also. It work for me :). Guess running a 333mhz is fine as I run all the SNES games at this mode.[/quote]