The Big MegaFlashROM SCC+ SD Topic | MSX Resource Center (Página 78/96)

Expert (74)

23-02-2017, 13:31

Thanks.
Will give it another try later.

Guillian wrote:

In that case there will not be conflicts between different Nextor kernels. So if you i
mplement the basic Nextor driver functions it should work fine.

Por enribar

Paragon (1206)

23-02-2017, 19:15

Unfortunately it doesn't work with my NMS 8245.
After choosing "S" and rebooting, It detects the SD card and then hangs.
Do I have to use another machine rather than Philips?

Por Guillian

Prophet (3516)

24-02-2017, 12:48

@enribar: I have updated recovery to V1.10. Install the new version and try again.

Por enribar

Paragon (1206)

24-02-2017, 20:25

Thankyou Guillian it works now!
I need some help on dumping... I dumped alot with the MSX Game Reader but SAVEROM and MGSAVE are a bit "obscure" to me, and more difficult to run with the MegaFlashROM.
Saverom shows me many slots and subslots and then adresses.
Since I can make more and more dumps with different parameters, can you suggest me from where to start?
I have some Takeru carts...

Por ChoroQ

Resident (33)

28-02-2017, 20:32

The MegaFlashRom SCC+ with 512kb works perfect in my VG 8235. When I boot the 8235 up it shows 512kb ram. But when I insert the cartridge in my 8220 it only shows 64kb when booting up. Why doesn't the 8220 show 512kb?

Por Grauw

Ascended (10717)

28-02-2017, 21:10

I think it doesn’t actually count the RAM, the amount is hardcoded in the BIOS ROM, I seem to recall something along those lines. And maybe the 8235 has a later BIOS revision which does count it?

At least here it mentions a jumper on the main board controls the amount shown, I don’t know what it does exactly but I think its value is read out by the BIOS ROM to determine what value to show.

Anyway, I think despite what the boot-up screen says, you probably do have 512K RAM at your disposal. Otherwise, you wouldn’t be able to use MSX-DOS2. I think in DOS2 you can type the MEMORY command to confirm the amount of memory (might be a COMMAND.COM 2.44 feature).

Por Guillian

Prophet (3516)

01-03-2017, 09:28

@enribar: you can dump your Takeru cartridges using SAVEROM. Insert MFR SD in slot 1 and Takeru cartridge in slot 2.
SAVEROM TAKERU.ROM
Primary Slot: 2
Select Type: Normal
Begin Address: 4000
End Address: BFFF

That will dump a 32K ROM. The addresses depend on the size of the ROM.
If you want to be sure you dump all the ROM, use start = 0000 and end = FFFF.

@ChoroQ: as Grauw said, most MSX2 does not count the RAM at boot and show a fixed amount. But the RAM will be available. Just check it typing MEM or MEMORY in command line.

Por ChoroQ

Resident (33)

01-03-2017, 22:05

Thanks Grauw and Guillian. I will test it when I can type something with my 8220 (keyboard is missing a lot of springs). At this moment I can just play roms with joystick.

Por enribar

Paragon (1206)

02-03-2017, 23:13

@guillian: thankyou it works now!
My main problem was in fact the mapper choise between "Normal", "ASCII", "Konami", etc. At the end I selected "Normal" and funal dumps work on emulators.
I made 2 dumps of each carts, 32KB and 64KB, and compare them: the one of 64kb have more or less 50% of blank space, so 32KB is the right size.
My main worry is making uncomplete dumps (missing data) but I think such a ROM will not work on emulators.
Btw, the 64KB ROM works as well on emulators, even if it has blank space.
Thankyou for making the "S-Option" :-)

Por Manuel

Ascended (19325)

02-03-2017, 23:43

The 64k dump will contain enough information to reverse engineer the mapper type, for most cases. So it's for special cases. Most smaller ROMs do not have a special mapper and will dump fine like you did with Normal option. You can underdump with 64k dumps if there appears to be a mapper behind it, but if there's not, you may have to trim them if the ROM appears to be smaller, indeed.