forums.ps2dev.org

[realjoeeye1]

Sys:401M33
I tried to use the ME, but got the 8002013C error code. I checked the .prx file, which used functions in sysreg.prx, but there is no such a file in my flash0, and maybe it need the kernel mode.

How can I use the ME on PSP with 4.01M33? Please help.

THX.

[J.F.]

Do a search on ME for old threads. I posted both a prx and an example of using it.

[realjoeeye1]

I saw your posts,J.F. but the download link of your sample code may be broken or I'm banned to download it.
I read many posts, and made a prx to use the kernel mode. But the functions in the prx don't work. No error code received but the functions just not work like they are not be called.

[J.F.]

http://www.mediafire.com/download.php?ahbmqxooqwq

Try that. It works fine on my slim in 4.01 M33-2. It has the clock setting code disabled. You can't change the cpu clock while the ME is running. The code there shows how to init the ME, start running code, set flags, and cleanup.

[realjoeeye1]

Many thanks!!

[realjoeeye1]

Is the "|0x40000000" opration means the ME has another address to access the memory? Are the "|0x40000000" address on ME and the original address on SC pointing to a same place?

[hlide]

nope it means we want to read/write into uncached segment as both processors cannot share the contents of their respective caches. The "|0x40000000" operation gives the same result in both processors : bypass the cache update, don't read/write in the cache even if there may be a hit but directly in main ram, vram or scratchpad.

[J.F.]

[hlide]

yeak, just forgot vram and scratchpad is specific to main processor :).

[realjoeeye1]

I've not used ME to access the VRAM. When load my prx, it received an error code:800200d9, like there was not enough memory to allocate. I used PSP_HEAP_SIZE_KB(10*1024) both in prx and eboot.pbp, it doesn't work.

[realjoeeye1]

I've tried J.F.'s sample code, the EBOOT.pbp already compiled did not work, it received an 80020001 error code loading the .prx. But when I recompiled it, it works well! Maybe I have to rewrite my codes based on J.F.'s MediaEngine.prx.

[realjoeeye1]

I'm not sure what the sigmask and sigset exactly mean, can J.F. give a simple explanation?

[J.F.]

[J.F.]

[realjoeeye1]

Yes, I'm sure I've put the mediaengine.prx to the same folder with the EBOOT.PBP. It didn't work on the old EBOOT.PBP, and work fine on the new EBOOT.PBP that I compiled.

Thanks!

[realjoeeye1]

[realjoeeye1]

[J.F.]

[realjoeeye1]

[J.F.]

No problem. With modern CPUs doing bus snooping, many people haven't learned those old-school cache coherency lessons. :)

[realjoeeye1]

I used the ME to IDCT a 8X8 short block, but it doesn't work correctly.

Codes:


static int idct_me(int start_block)
{
idct_start((short*)(int(&dct_recon[start_block][0][0])|0x40000000));
return 0;
}
static void idct(int start_block)
{
int err;
err=BeginME(mei, (int)idct_me, start_block, 0, 0, 0, 0);
/* if (err < 0)
printf(" failed! Error calling BeginME. %d\n",err);
else
printf("BeginMe OK. %d\n",err);
sceKernelDelayThread(300000); */
}

idct_start() is a function to do the IDCT, it can do that correctly on th SC. But when I used ME as above code, I got an incorrect result, and sometimes PSP crashed.

[J.F.]

Using caches:
SC: store data to input array, then flush dcache
ME: invalidate input array (not flush!), then process data, then flush dcache for output array
SC: invalidate dcache for output array (not flush!), then read results

When you use BeginME(), remember that the data won't be valid until the ME is done. There's a function to check if the ME is done, and one to wait for the ME to finish.

If you don't want to mess with the caches, always use the uncached pointer EVERYWHERE for EVERYTHING. Also, flush/invalidate the dcache for the arrays BEFORE messing with them to make sure that you're using the contents of memory instead of the cache.