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			<title>Macintosh Plus: SCSI Device and Driver Support Limits</title><body class="ac-gn-current-support">
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<h1 id="main-title">Macintosh Plus: SCSI Device and Driver Support Limits</h1>
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<div id="intro-container"><div class="truncate"><div class="attr SYMPTOMS"><div class="attr TOPIC"><FONT SIZE=4> </FONT><BR>
<FONT SIZE=4> <BR>
How many SCSI drivers does the Macintosh Plus support according to Apple's<BR>
specifications?  Are there any restrictions on the type or nature of those<BR>
drivers?<BR>
 <BR>
</FONT></div></div> <!--  attr Symptom  --></div> <!--  truncate --></div> <!--  intro-container --><div class="clear"> </div>
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  <div class="attr SUMMARY">
There are no &quot;published&quot; specifications regarding how many SCSI drivers<BR>
the Macintosh Plus can have loaded into memory at one time.  A typical<BR>
SCSI driver uses about 5K of memory.  If you attached seven SCSI devices,<BR>
you would use around 35K of memory for their drivers.  This 35K or even<BR>
50K does not pose a problem.  The real problem you have with the Macintosh<BR>
Plus and SCSI devices is the electrical limitation.  Four to five devices<BR>
is probably the maximum that you can put on the SCSI bus due to the load<BR>
placed on the SCSI bus by the SCSI devices.<BR>
<BR>
<BR></div>
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<div class="mod-date">Published Date: Feb 18, 2012</div>
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