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From: phil@pepsi.amd.com (Phil Ngai)
Newsgroups: comp.sys.ibm.pc
Subject: Re: ESDI or SCSI or RLL?
Message-ID: <29854@amdcad.AMD.COM>
Date: 12 Apr 90 20:01:24 GMT
References: <18758@boulder.Colorado.EDU> <27800006@adaptex> <6137@jarthur.Claremont.EDU>
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Reply-To: phil@pepsi.AMD.COM (Phil Ngai)
Organization: Advanced Micro Devices, Inc. Sunnyvale CA
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In article <6137@jarthur.Claremont.EDU> rspangle@jarthur.Claremont.EDU (Randy Spangler) writes:
|Now, my only question is "What's the difference, hardware-wise and 
|functionality-wise, between the PIO and bus master?"

One difference is that bus master doesn't work in systems that use
memory mapping, such as 386s with QEMM-386 or 386Max. The memory
management software doesn't tell the bus master what's going on...



--
Phil Ngai, phil@amd.com		{uunet,decwrl,ucbvax}!amdcad!phil
The War on Drugs is the modern day Inquisition.