Re: Sider II HD unit

[Patrick Schaefer <pa.schaefer@fz-juelich.de>]

stephen e buggie wrote:
> 
> If I were you, I would SCSI-ize the Sider.  Add a big-capaicity SCSI unit!

Did you try this? I have connected a SCSI drive to my Sider interface
and I was able to read and write single sectors, but there were two
problems:

a) the SCSI drive has 512 byte sectors, the original one seems to have
256 byte sectors. After PR#7 the controller firmware reads the first
block into memory $BF00. A 512 byte block overwrites the $C000 page with
the softswitches, therefore the system hangs.

b) the Sider installation program reports a status error. The SCSI
drive, even though very old, reports an extended status with 7 bytes.
The installation program expects the old SCSI-I format with only four
bytes.

The interface firmware supports some non-standard SCSI commands: $0D,
$0F, $E3, $E4. 

I have the 1986 ROM version with the DOS3.3 based installation program.
The '88 ProDOS setup disk does not work with the old ROM.


Patrick