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Subject: Re: SCSI vs parallel debate
From: Bruce@offserv.pcb.co.za
Reply To: mapug@shore.net
Date: Sat Jan 28 02:05:17 1995

Dear fellow LX-200 techo-junkies,

I have only had my LX-200 for 2 months and still am enjoying discovering the universe with the direct transmissions of photons to my eyeballs (ie CDD imaging is still some time away), even though I have not had much luck lately with warm,humid anti-cyclones from the Indian ocean causing much hot,humid and rainy weather.

Being in the computer business, I do however have some contribution to make in the SCSI/Parallel interface debate.

SCSI is a much more versatile interface than the old "Centronics" parallel (//). Devices that transmit/receive data over the parallel i/f of a PC are bound to be limited in some form & functionality or another. It might work on one PC and not another. There is no formal spec, rather industry ad-hoc improvisations. Also, you are limited to PC's. This is from our experience with Laplink, etc. Data transmission becomes unreliable over 3 meters over a // i/f.

They both communicate data in 8 bits in Parallel but there is more overhead in the SCSI protocol that //. Bandwidth is debateable. Rarely does one achieve full spec speed.

In SCSI, it depends on your interface. We have always had good results with Adaptec controllers. They make a really neat PCMCIA SCSI adapter, the APA460, which we sell for SA Rands R1125 (probably about US $275) which I would suggest anyone needing a SCSI Adapter for there laptop have a look at.

This should give one good bandwidth for downloading those large CCD images. Of course, your notebook should have a PCMCIA slot. I would avoid the //-SCSI adapters since our experience has shown them to be a bit messy.

If I was buying a CCD imager, I would definitely go for the SCSI.

Cheers for now and starry skies to everyone,

Bruce Gillespie Network Engineer & Internaut

Yeoville, Gauteng, South Africa

(Bruce@PCB.Co.ZA)