C/C++ Programming Help Thread

Hi,
I'm having some difficulties on finding the way to implement memory stick access. I've done some pretty extensive searching, but can't completely grasp the right way.
I think I have found the way, please elaborate:

Code:

---

fd = int

int main(){

while(1){

fd (sceIoOpen("ms0:/", O_RDONLY, 0777));
  if(fd <= -1);
  printf("ERROR: Please insert MemoryStick !\n");

  else;
  printf("MemoryStick mounted to ms0:/\n");
  break;}

}

---

Since I'm still learnig proper C, there could be syntax errors on my part.
I based the above code after trying to understand the pspsdk libraries by DAX.
Hope someone can help me out.

your trying to open the ms0:/ like its a file which you cant do. Dont you thikn that if someone is playing you game/using your app they would most likely have a memory stick in?

Zitat:

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Zitat von Xsjado7

your trying to open the ms0:/ like its a file which you cant do. Dont you thikn that if someone is playing you game/using your app they would most likely have a memory stick in?

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Specially 'cause technically you people won't be able to have you hb if they don't have a MS

This is really the kind of useless test you'll do, 'cause it'll always be true. How about checking to see if a file exists for example?

Cheers

Spoiler for Code Stuff:

other things, you dont do

Code:

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fd = int

---

you do

Code:

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int fd;

---

Code:

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fd (sceIoOpen("ms0:/", O_RDONLY, 0777));

---

should be

Code:

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fd = sceIoOpen("ms0:/", O_RDONLY, 0777));

---

im pretty sure sceIoOpen() returns 0 or lower on failure

Code:

---

if(fd <= -1);
  printf("ERROR: Please insert MemoryStick !\n");

---

should be

Code:

---

if(fd <= -1) printf("ERROR: Please insert MemoryStick !\n");

---

Code:

---

  else;
  printf("MemoryStick mounted to ms0:/\n");

---

should be like

Code:

---

  else
 {
  printf("MemoryStick mounted to ms0:/\n");
 }

---

another thing, why do you break your loop when it runs it? It completely defies the purpose of having it

Do what placo mentioned, check if ms0:/MEMSTICK.IND exists
-= Double Post =-
Quick question
If i had some code like this:

Code:

---

while(1)
{
    while(1)
    {
    }
}

---

How would i brake both loops when im in the second?

Assuming all you're doing is checking if the memory stick is inserted or not...

You could also use a callback like shown in /samples/ms/callback to capture when a memory stick is inserted or ejected.

In kernel mode, you can read the controller data and the PSP_CTRL_MS bit is set when a memory stick is present.

The best solution is to use MScmIsMediumInserted() from pspmscm.h, the function returns 1 if the ms is inserted, 0 if it is not.

@Xsjado7, it could turn out to be a plugin :rolleyes:

Zitat:

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Zitat von Xsjado7

Quick question
If i had some code like this:

Code:

---

while(1)
{
    while(1)
    {
    }
}

---

How would i brake both loops when im in the second?

---

Code:

---

int running = 1;

while(running)
{
        while(1)
        {
                ...
                running = 0;
                break;
        }
}

---

Try and stay away from while(1) loops and use while(!done) style instead.

Zitat:

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Zitat von BigSanFrey

@Xsjado7, it could turn out to be a plugin :rolleyes:

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Plugins still need to be loaded from a memorystick

@Insert_Witty_Name, i was thinking about that but i thought you might be able to do something like a double break. Thanks for the help though :)

not if it is replacing a lftv_plugin.prx or camera icon :)

The best way, in my opinion, to check if the memory stick is inserted would be to use dirents, and open the memory stick that way (argument has to be ms0: I believe, and not ms0:/), this also paves the way to checking the existance of other folders if required, thats how I check for the presence of the memory card and folders in Project4 (packaged into another fucntion of course). Alternatively, you could use the methods posted above by Insert_Witty_Name if no folder checks are required.

Oh, I also got my toolchain compiling, I just retried it an hour or so later and it worked fine.

-Aura

@Insert_Witty_Name:

Thank you, that's what I am looking for.
To do that kind of kernel call I would need to put it in a external prx, because the app needs to be in user mode. Am I correct, or do I still not understand the kernel and user mode differences ?

@Aura::

So the code I put up will work if I change ms0:/ to ms0 ?

@the other replies:

True the memstick will be present when starting the app. But I could be the user decides to swap the stick before executing the "real function" of the app.

Thanks you all, so far

Zitat:

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Zitat von JoyforPSP

Am I correct, or do I still not understand the kernel and user mode differences ?

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I'm not sure, as I don't have any codes with me because I'm at school, but I think one of those functions may work in user, otherwise yes you will need to make a kernel wrapper (check on PS2Dev).

Zitat:

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Zitat von JoyforPSP

So the code I put up will work if I change ms0:/ to ms0 ?

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No, you are attempting to open a file there, ms0: is not a file, but a folder, you need dirents check the header files, you need something like sceIoDopen.

Zitat:

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Zitat von JoyforPSP

True the memstick will be present when starting the app. But I could be the user decides to swap the stick before executing the "real function" of the app.

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If you are continually running a check to see if the memory card has been removed, the the original option would be best, using dirents is only really handy for checking once (or every so often), if you were to constantly check in another thread if the memory card had been removed, the dirents method would probably lag the system.

-Aura

Or you just do it the easy way and use PSP_CTRL_MS

You might wanna look up on C syntax a bit more JoyForPSP. Your code wouldn't even compile.

Also, you can open ms0: for raw memory stick access.

MScmIsMediumInserted() from pspmscm.h is a user mode function and is probably the easiest method to achieve what you want.

Ok. Thanks again for the replies.
I'll look into MSmcIsMediumInserted() when I get home from work. You all seem to agree it is the easiest to implement and fits my needs.

And yes, I DO need to get a hang of the C syntax.
I'm still awaiting my ordered book in order to learn C.

Zitat:

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Zitat von JoyforPSP

Ok. Thanks again for the replies.
I'll look into MSmcIsMediumInserted() when I get home from work. You all seem to agree it is the easiest to implement and fits my needs.

And yes, I DO need to get a hang of the C syntax.
I'm still awaiting my ordered book in order to learn C.

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Just out of curiosity.. Do y9ou care to say why you need to check if the memory stick is inserted?

Cheers

Zitat:

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Zitat von placo23

Just out of curiosity.. Do y9ou care to say why you need to check if the memory stick is inserted?

Cheers

---

Yeah, I'm trying to code an app which does some copying to the memstick.
Next step is checking for free space, but first I'll try and get this part working, then I'll start looking into the free space and the actual copying.
I hope I can release my app sometime this year :p

I've been programming less than a year, and I've had no lessons or anything, I don't even own a programming book, I've just picked it up over the months looking at source code, and checking, in my opinion, the best resource -> http://www.cplusplus.com/ (Google also helps).

Right, now maybe I'm being stupid/blind/both, but I updated my toolchain, and I can't find the macros for PSP_LOADMODULE_APITYPE_XX XX anywhere and its bugging me, I dislike using the predefined functions as one didn't work but without that macro or its equivilent value I can't continue on, so if anyone could be so kind as to point out which header it is in, I'll be very thankful :p

EDIT: Found it, it appears to have been moved to pspinit.h, just went through all the header files to find it :Argh:

-Aura
-= Double Post =-
I'm having a problem with possibly my compiler (both before and after my toolchain update)... I'm trying to create a volume bar in Project4, so I've been using the impose_driver stuff, but whenever I tried to load my prx I got the 0x8002013C error, so I moved to use support.prx from LightMP3 as a test... it worked fine, so as a random test I decided to compile the support.prx myself from the source code, and it doesn't work. Any ideas as to why that is?

Quick question, if i have something like this:

Code:

---

u32 COLOUR 0x00ff00ff

---

(A,B,G,R)
how would i go about modifying just the blue value? I want to increase it without changing the others. Kinda like:

Code:

---

u32 COLOUR 0x00ff++00ff

---

Any ideas? Sorry for bad explanation

COLOUR = (COLOUR & 0xFF00FFFF) | ((COLOUR + 0x00010000) & 0x00FF0000);
More or less.

is it possible at all to stop the psp from shutting down after some1 holds the power button up, i'd imagine it's hardware wired in, but i still wanna check to see if it's remotly possible

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Zitat von slicer4ever

is it possible at all to stop the psp from shutting down after some1 holds the power button up, i'd imagine it's hardware wired in, but i still wanna check to see if it's remotly possible

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No. Its the hardware.

i figured as much, thanks for confirming it

Zitat:

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Zitat von slicer4ever

is it possible at all to stop the psp from shutting down after some1 holds the power button up, i'd imagine it's hardware wired in, but i still wanna check to see if it's remotly possible

---

You CAN disable this, its not hardware at all. The function you require is in psppower.h and is:

Zitat:

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/**
* Lock power switch
*
* Note: if the power switch is toggled while locked
* it will fire immediately after being unlocked.
*
* @param unknown - pass 0
*/
int scePowerLock(int unknown);

---

-Aura

Hey guys, im looking at doing some effects (transition like) for a game. I want to try and have a fade effect so first i need a function to return the colour of every pixel on the screen into an array. Would something like this work?

Code:

---

int count;
int pixely;
int pixelx
u32 pixelcol[130560];//130560 is amount of pixels on screen

while(pixelx <= 480)
    {
                pixely ++;
                count ++;
                if(pixely > 272)
                {
                          pixelx ++;
                          pixely = 0;
                }
                pixelcol[count] = getPixelScreen(pixelx, pixely);
    }

---

You're thinking about it the wrong way.

Draw a quad over the screen last thing in your drawing loop.

Set the alpha of the quad based on if you're fading out or fading in.

Fading out, then you want to increment the alpha value from 0-255. Fading in you want to decrement it from 255-0.

oh, nice. Man thats a good idea(its not that amazing but just a nice way of doing it) i never thought of doing it like that. Thanks man :tup:
-= Double Post =-
just for future reference, if for some reason i need it, would my code still work?

Yes, as IWN said use a quad with a varying opacity. On the PSP (probably on soem PCs as well) avoid huge loops like that. I've done motion blur in LUA and the frame rate is awful.

Even after narrowing down the blurring zone to be 480x10 i still was getting like 3 fps...

dang, thats some seriously choppy stuff. Thanks for the help guys. The transitions/effects add that extra bit of professional-ism to a game/app

Zitat:

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Zitat von Auraomega

You CAN disable this, its not hardware at all. The function you require is in psppower.h and is:



-Aura

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All that does is disable sleep mode, actually.

Xsjado - Heh...

You'd be surprised at the very simple arithmetic used to make some of the most amusing transitions ;) I'm using a neat transition system in my current project. Transitions are fun to make, then actually being able to make use of them really sets your game apart from others.

Here's one that makes the scene underneath (the next state hint hint) kinda "pop" out of no where (well, depends on the transition speed)

Code:

---

// Declare these where ever they can be accesible
bool bEntering;        // Flag to tell if were entering a game state
Vector2D vTransition;  // 2D Vector class or structure used for transitioning game states
const int TRANSITION_X_SPEED = 10; // The transitions speed x-coordinate wise
const int TRANSITION_Y_SPEED = 6;  // " y-coordinate wise

// Initialize (call this when initializing the next state)
bEntering = true;
vTransition.x = 0.0f;
vTransition.y = 0.0f;

// Think (call this during the thinking part of the game states, out of any switch statement or w/e)
if (bEntering)
{
  if (vTransition.x >= SCREEN_WIDTH / 2)
  {
    bEntering = false;
  }
  else 
  {
    vTransition.x += TRANSITION_X_SPEED;
    vTransition.y += TRANSITION_Y_SPEED;
  }
}

// Draw (call this in the drawing part of the game states, out of any switch statements or w/e)
if (bEntering) // Replace oslDrawFillRect(x,y,x2,y2,color) with whatever your graphics library supports
{              // Draw our neat transition GFX (a square expands - it's 4 points are then used to draw black rectangles everywhere BUT inside of it, the stuff inside it is the next state being drawn below it)
  oslDrawFillRect(0, 0,
                  int (SCREEN_WIDTH / 2 - vTransition.x), SCREEN_HEIGHT, RGB(0,0,0))

  oslDrawFillRect(int (SCREEN_WIDTH / 2 + vTransition.x), 0,
                  SCREEN_WIDTH, SCREEN_HEIGHT, RGB(0,0,0));

  oslDrawFillRect(int (SCREEN_WIDTH / 2 - vTransition.x), 0,
                  int (SCREEN_WIDTH / 2 + vTransition.x), int(SCREEN_HEIGHT / 2 - vTransition.y), RGB(0,0,0));

  oslDrawFillRect(int (SCREEN_WIDTH / 2 - vTransition.x), int(SCREEN_HEIGHT / 2 + vTransition.y),
                  int (SCREEN_WIDTH / 2 + vTransition.x), SCREEN_HEIGHT, RGB(0,0,0));
}

---

Not the best, nothing crazy, etc. but hey it's one ;)

P.S. it'd be nice to have a huge collection of transitions. Sure some will be more render-engine specific but hey it'd be a good developer resource

Zitat:

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Zitat von SG57

P.S. it'd be nice to have a huge collection of transitions. Sure some will be more render-engine specific but hey it'd be a good developer resource

---

I was thinking about that earlier. Just gather a load together into a library and port it to work with a few different graphics libs like OSL/TriEngine/Graphics.h

Is there any way to get EBOOTs to be loadexec'ed from flash0-3? Loading PRX files works fine, but trying to use the loadExec calls I get an error (SCE_KERNEL_ERROR_ILLEGAL _PERM_CALL I believe). I'm not sure if there is any work around from this?

-Aura

Zitat:

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Zitat von Auraomega

Is there any way to get EBOOTs to be loadexec'ed from flash0-3? Loading PRX files works fine, but trying to use the loadExec calls I get an error (SCE_KERNEL_ERROR_ILLEGAL _PERM_CALL I believe). I'm not sure if there is any work around from this?

-Aura

---

You can't just use sceKernelLoadExec for EBOOTs. If I recall correctly, you have to first decompress the .ELF from the EBOOT. Check out this thread.

http://forums.qj.net/f-psp-developme...eps-64080.html

OMG, I could kiss you right now :humped: I've been trying to get this working for a while and have been reduced to using the new ms versions of the loadexec (which work with EBOOT.PBP natively without any messing around). All I can say is thank you deeply, and I can't believe it was something that simple :p

-Aura

EDIT I:
Hmm, no wait, seems to not work flash - flash. Ms0 - flash works fine, but flash - flash just fails, oh well, back to the drawing board...

EDIT II:
It works flash - flash in 1.50, but not in 3.XX, which is where this app is targeted.

Zitat:

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Zitat von Auraomega

OMG, I could kiss you right now :humped: I've been trying to get this working for a while and have been reduced to using the new ms versions of the loadexec (which work with EBOOT.PBP natively without any messing around). All I can say is thank you deeply, and I can't believe it was something that simple :p

-Aura

EDIT I:
Hmm, no wait, seems to not work flash - flash. Ms0 - flash works fine, but flash - flash just fails, oh well, back to the drawing board...

EDIT II:
It works flash - flash in 1.50, but not in 3.XX, which is where this app is targeted.

---

Yes, I remember hearing something about not being able to run EBOOTs from the flash in 3.xx, but I didn't know if it was true or not. Do they still run from the memory stick? Maybe copy it to the memory stick before booting? Is this an EBOOT that you coded? Maybe you could recompile it into a PRX.

I need some help. Im trying to get a program to recognize the motherboard of the PSP, so I did this:

Code:

---

if ((tachyon = 0x00300000 && baryon = 0x00040600))
        {
        printf("Motherboard = TA-081 1g\n");
        }

---

I get error

Zitat:

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error: invalid lvalue in assignment

---

I know it has to do with the (( and the &&, how would I code that part so the program would 'use' both tachyon and baryon?

If statements use two ='s instead of one. Change it to:
if ((tachyon == 0x00300000 && baryon == 0x00040600))

Hope that helps.

Zitat:

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Zitat von Durka Durka Mahn

If statements use two ='s instead of one. Change it to:
if ((tachyon == 0x00300000 && baryon == 0x00040600))

Hope that helps.

---

Aha, thanks! I appreciate the help and it works now.

Zitat:

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Zitat von Judas

Yes, I remember hearing something about not being able to run EBOOTs from the flash in 3.xx, but I didn't know if it was true or not. Do they still run from the memory stick? Maybe copy it to the memory stick before booting? Is this an EBOOT that you coded? Maybe you could recompile it into a PRX.

---

Yeah, I've not actually read it anywhere but I assumed this would likely be the case. It is an app I made, and compiling in prx format is possible, but it physically needs to be loadExec'ed from flash, not just loaded as another module, I'm not actually being rejected as such, its attempting to load it from flash, and not giving any errors, but then it just returns me to the XMB (Project4 in my case), I'll do some more research into it, as I also want to be able to do this with code that is not my own.

The only other thing I can think of is if I write my own driver like that of DevHook and somehow trick the PSP into believing that its loading from ms0:/, but so far I've had no luck in that department either.

If you can think of any other options I'm all ears, the more ideas I have the more likely I am to find a work around to my problem.

-Aura