Looking for info about ATAPI ATA Controllers

[xelos]

ATAPI ATA Controller

Hello everybody,
I'm searching the information about IDE controllers (ATA Controller), especially for the registers and reading/writing data on hard drives. Also, I need an information about addressing of hard drives (cylindres/heads/sectors) - how it works?

 

[alcatraz1972]

Re: ATAPI ATA Controller

Look this book:

Title : The SCSI bus and IDE interface; protocols, applications and programming
Author : Schmidt, Friedhelm


I dont have the electronics version

 

[robswu]

Re: ATAPI ATA Controller

Hi,

The information you are looking for are all in the ATA specifications, which are free for download. The ATA controller implementation of the interface registers varies between the different controllers (8bit interface vs. 32bit interface) so you probably have to go download the vendor datasheets for that.

 

[dainis]

Re: ATAPI ATA Controller

/http://www.t13.org/

 

[Big Boy]

Re: ATAPI ATA Controller

On t13 indeed, if I remember well. I suggest starting with ATA4 specs, which cover most of the things you need to know, though the more rescent specs cover things such as ultra DMA and some of those latest development. If it's for a micro-controler project for example, you probably won't need 33MB/sec transfer anyway!

Reading/writing is pretty easy once you know the basic procedure. The most tricky part is doing the read/write protocol sequence when transfering the sector data, but this can be implemented as stand-alone functions, and is well-doccumented.

I would suggest starting with PIO transfer.

Also, there are two addressing modes, which are CHS (stand for Cylinder-Head-Sector), which it outdated, but probably still supported by all drives (though you can only access the begining of the disk), and have become obsolete with the second addressing mode, which is LBA. In LBA, everything is easy, as you just tell which sector, starting from 0, you want to read (0 to 268,435,455), the high address limited by you HD capacity. This give access to 137GB. Every drives larger than about 400~500MB support LBA. It is funny though, as I remember when I tested with an old 420 megger, it didn't support LBA

The first function to implement, to test if you can acces the drive, is the IDENTIFY DEVICE command. Once you send the command, you read the data block just as a regular sector (256 words).

 

[mostafa_elwakeel]

Re: ATAPI ATA Controller

hi
you can find good information in this link
**broken link removed**
in the Specifications folder(Home / Specifications / ATA-ATAPI )
thank you

 

[sonal]

ATAPI ATA Controller

I dont have the electronics version