This adapter LVD compatible?

[jaybert]

Can someone tell me if this 68pin >> 80pin scsi adapter is LVD compatible?
http://store.yahoo.com/sagetac/sca8ad.html

I just purchased that not realizing that I would need one especially for LVD

 

[pjs]

I went to your link and I can not tell.

I would assume that it is NOT lvd beings it does not explicitly say so and lvd needs an extra set of data lines.

Paul

 

[jaybert]

http://www.symmic.com/computer/adaptor/S80D68LS.htm

Thats the new one i purchased...it says LVD so i can assume it'll work correct? Also, what exactly do you mean by the extra data lines?

 

[pjs]

LVD means Low Voltage Differential.

Non-lvd is single ended: 16 data bit lines are refferenced to ground.

With differential, there are two lines per data bit. A positive and a negative line.
The positive line is compared to the negative line, not to the ground line (withing limits).

It is the difference between the positive and the negative that determines the logic state of a particular linr. So for wide scsi (16 bits), 32 actual data lines are needed, compared to 16 for single ended wide scsi.

The advantage of differential is that common mode noise (a voltage value that BOTH the positive and negative lines have) is ignored (up to a point).

What this boils down to is that data transfers are more reliable, or the data transfere rate can be higher for a given reliability (for a given error rate).

Paul

 

[jaybert]

so basically the cards themselves look the same, its just the internal mechanisms/workings of the card?

 

[TuOni]

hey this is a good post

 

[pjs]

Yes, the cards look the same, the connectors, 4 pin power, 80 pin sca and 68 pin scsi are the same, just the wiring on the circuit board is different.

Paul