A few questions about using sd card

[kof888]

Recently I bought another sd card device to use on the dc

although I already have the cloned gdemu and mode, but I am still very interested in DreamShell, because I have not used DreamShell for many years, so I have a few questions to ask

1 Can I run my own compiled programs in DreamShell? Such as elf or bin, I don't know what is the process of loading files in DreamShell

2 I tested it, depending on the compatibility of iso_loader with sd card (especially for some games that need to run programs in ip.bin separately)

3 Using sd.bin to play the game BIOHAZARD CODE VERONICA PLUS, is there a bug of infinitely taking tiger head gems in cd2? I don't have a hard disk, I just tested it on the sd card and found that this bug will also exist. I wonder if this problem also exists on the hard disk?

4 Does using sd.bin not support reading CDI files like atomiwaves does? I wrote a piece of code like this before the cdi game started, the display is black, but the test on gdemu is normal, if you remove this code, then it works fine in DreamShell

syscall C0,
similar to the following
................................
r8=0x8C0000C0
mov.l @r8, r0
mov #h'1C, r4
jsr @r0
r7=0;


Thank you for your responses

Please forget my bad English, I don't speak English, I used google translate

[megavolt85]

1) yes, execute from app File Manager
2) most games don't work from IP.BIN
3) yes, same problem with HDD
4) CDI is not the best choice for SD, even if the game starts it runs much slower than reading ISO or GDI-Opt

your code is call to function gd_dmaread_stream, R5 can be contain pointer to buffer with two parametrs (LBA and sector count)
SD don't have DMA and this function not work in most games

[kof888]

(02.03.2022 18:39)megavolt85 писал(а):  1) yes, execute from app File Manager
2) most games don't work from IP.BIN
3) yes, same problem with HDD
4) CDI is not the best choice for SD, even if the game starts it runs much slower than reading ISO or GDI-Opt

your code is call to function gd_dmaread_stream, R5 can be contain pointer to buffer with two parametrs (LBA and sector count)
SD don't have DMA and this function not work in most games

Thanks for your reply

I probably know something, but there are still some questions I want to figure out

1 How to use the specific method? For example, I wrote an elf program that loads a bmp file and displays it on the screen. How should I add it to the app File Manager?

2 Then the method of reading in iso_loader is to directly read the main program file (1st_read.bin) executed in ip, right?

3 In the near future, I will upload the modified main program file and the complete gdi image

4 So what other methods are used in the reading program of the sd card? Is there any information available?

[megavolt85]

1) put your ELF or BIN to SD card and open in filemanager, same as open exe in windows
2) right
3) it's fine
4) supported all methods, but when CPU use MMU, access to RAM possible only over DMA, SD don't have DMA channel and can't write data to RAM
P.S. all WINCE and few KATANA games use MMU

[kof888]

Thanks again for your reply, I'll try it first

[fafadou]

Цитата:3 Using sd.bin to play the game BIOHAZARD CODE VERONICA PLUS, is there a bug of infinitely taking tiger head gems in cd2? I don't have a hard disk, I just tested it on the sd card and found that this bug will also exist. I wonder if this problem also exists on the hard disk?

Now with hdd the 0.6.11 loader avoid this issue
For resident evil code veronica plus with hdd we suggest 0.6.11_se loader here :
http://www.dc-swat.ru/forum/thread-2646.html
it's why I really wish to see one day a mix with 0.7.x loader and 0.6.11 in order to boot some games without patch like ooga booga, or the last reluctant games.

There is also a sd.bin 0.6.11 version, I don't try it about the tiger issue...

For sd card we recommend the 0.6.6x beta version you can also find via the link.