Questions about SCSI

[melott]

I know this has been talked about from time to time
BUT can  someone explain about SCSI in terms
that us putzs can understand.
In my case the A3000 SCSI controller or WarpSCSI,
and SCSI controllers in general.
Like rules for 'Termination'
 (yes I know it needs to be terminated but I have several drives connected)
Do you set power to the bus and Terminate the
drive or just terminate the drive?
What about 'Parity' ?
What about 'ReSelection'???
And all those neat little jumpers on the drive  
It seems that most of us just do the
"Trial & Error" method. It would be nice if I knew
something like "If this is this, then that has to be
that"  rule of thumb.

Mel Ott

[melott]

Yes, we are fumbling in the dark most of the time.
Answers like above " the cable is short enough " ect.
don't help much.
And what about termination power to the bus, do I set it
on a device or all devices, or none of the devices??
There are lots of little things that add up and you
need  some kind of guide line.
We need some indepth answers here.

Mel Ott

[melott]

OK ..... now whats the difference between the
internal port and the external port on my A3k
besides the internal port is 50 pins and the
external port is a 25 pin and SCSI-1 ( I think ).
And why, on the origonal commodore installed
harddrive did the drive have a label on it saying
the tremination was removed when infact it
was the last drive on the chain and according
all popular opinion it should have been terminated??

Mel Ott

[melott]

Hmmm..... :-D

So it sounds like I made a mistake..
I added a 'HD50' pin adaptor on a bracket using
ribbon cable and the internal C= SCSI port, thinking
the 50 pin internal port would be better, but it
sounds like unless I removed the MoBo resistor
pack its not going to work,  this is for external
drives as I am using the WarpSCSI for the internal
drive. And if I understand correctly the C= 25 pin
external port  does not restrict me from using
a 68 or 80 pin drive with the right adaptor ??

The MUD is thinning
Feel free to impart any bits of wisdom you have

Mel Ott
 :-D  :-D  :-D