Because of a discussion in the CPC scene I want to add extended ATA support in SymbOS, which increases the sector numbers from 28bit to 48bit. This will allow to access a maximum of 2TB with FAT32 instead of the current 128GB.

Can anyone help me with the following questions?

1.) where do I find a documentation how to set a 48bit LBA address with an IDE interface? I made some Google searches but without any success yet.

2.) do modern hard discs with a size of >128GB do not support normal ATA commands (28bit) anymore?

I know that already 128GB is completely oversized for a Z80 system, and that 2TB is just crazy. But because of question (2) some people are afraid, that you can't use modern hard discs anymore in the future, if you only use 28bit commands.

Already found it:
http://www.t13.org/technical/e00101r0.pdf

And:
"New devices implementing this 48-bit addressing are totally backward compatible with existing
hosts and host software. The usable capacity of the device will be limited to that addressable by
the host but the device will operate normally at that capacity."

Just FYI...

So, better spend some effort on SCSI support

I think that 128GB is sufficient for storing the whole production of MSX SW ever developed across the face of the world since 1983 to nowadays

I can make some v9990 movie files to fill it

ARTRAG: very much more than enough!

what is the data transport rate for the MSX?

The data rate is 162KB/s on the CPC (maximum), on a MSX2 it should be similiar or a little bit faster.
That means: 25.000 years for reading a 128PB harddisc
The funny thing is, that some experts in the CPC scene are sure, that they will write applications, which need this space.

The speed depends on the type of msx. ranging from 120KB/s to 716KB/s

Normally the IDE is quite slow on the turbo r when you compare it to novaxis SCSI. When the IDE code is completly in internal ram of the turbo r I expect it will be quite fast.

Interesting! Because it is executed in the external Rom catridge? The "fast mode", where Roms are copied into the Ram, doesn't take care about the Sunrise IDE rom?

No, in DRAM mode only BIOS(16K), BASIC (16K), KANJI (16K) and SUBROM (16K) are copied to RAM. (=64K)

In case of SymbOS using DRAM mode is 100% waste of memory. Programs that use plenty of BIOS calls may get some small boost.

Mostly this feature is usefull for tweaking BIOS routines.

Prodratron do you use any code from the rom?. On turbo R it's always better to run stuff from internal ram.

No, sorry, my question had nothing to do with SymbOS I just was interested about the MSX in general
Of course I already deactive the DRAM mode while booting SymbOS, and my IDE routines do not use the BIOS and run in normal Ram.

that will probably mean it runs faster already.. Btw also use LDIR otir etc instead of multiple LDI ,OUTI on turbo r