[Coco] Biggest OS-9/Nitros-9 HD?

[Alex Evans]

On Sep 23, 2005, at 4:49 PM, Dave Kelly wrote:

> Diego Barizo wrote:
>
>>   I've been reading the OS-9 manual, and I understand that the FAT  
>> uses 3 bytes - 24 bits - to keep track of the files sectors.
>> That would give 16777216 sectors, and at 256 bytes a sector,  
>> 4194304 Kb, or 4 Gb
>> Is that the maximum size of HD partition that OS-9 can work with?
>> What is the biggest HD any of you has ever used with OS-9?
>> Also, the manual says something about the files being able to be  
>> as big as the media. Did I get it right? Could OS-9 in 1985/6 work  
>> (theoretically) with files over 2 GB, something that Windoze  
>> machines could not do until the release of WinXP some 23 years  
>> latter?
>> Diego
>>
> Your math is correct. But look at your allocation table. 1 sector =  
> 256 byte x 8 bits = 2048 sectors of storage x 256 (sector size) =  
> 624,280 hard disk size possible.

So, you are saying that OS-9 can't even support a 720k floppy.   
Actually the maximum allocation table size is 65,536 bytes, or  
524,288 entries allowing 128M without sector clustering.  If you  
allocate using clusters of 32 sectors of 16k, then you can have media  
as large as 4G.