Re: [hatari-devel] ACSI emulation

["Roger Burrows" <anodyne@xxxxxxxxxxxx>]

On 15 Jan 2018 at 23:29, Eero Tamminen wrote:

> Hi,
> 
> On 01/15/2018 09:17 PM, Thomas Huth wrote:
> > On 15.01.2018 20:14, Roger Burrows wrote:
> >> For EmuTOS-related reasons, I just measured the data transfer rate of an
> >> emulated ACSI disk.  On my not-very-fast Linux system, it's about 5 times
> the
> >> maximum rate observed on real hardware (6400kB/sec vs 1300kB/sec),
> 
> If Hatari should emulate something in this regards, I think it
> should be interface speed, not some ancient storage medium.
> 
This IS interface speed I'm talking about.  Real disks may be slower.

> According to Wikipedia, first SCSI standard (on which ACSI is based?),
> has max speed of 5MB/s, and the SCSI chip in TT has max speed of
> 4MB/s:
> https://en.wikipedia.org/wiki/SCSI#Parallel_SCSI
> https://en.wikipedia.org/wiki/Atari_TT030#Technical_specifications
> 
ACSI is only implemented on Atari systems, so the only relevant interface is on 
real Atari hardware.  If you can get I/O at over 1500KB/sec, you should tell 
everyone how.

And the SCSI chip on the TT will not transfer at an effective rate above 
2MB/sec.

Roger