AST RESEARCH, INC.        TECHNICAL BULLETIN # 1594          10/01/96 
 
 
 
TITLE:  Bravo and 3COM 3C5X9 and Adaptec 2940
 
 
ISSUE 
 
   When a 3COM ISA 3C509 network adapter and Adaptec AHA2940 SCSI 
   PCI adapter are installed in the Bravo MS system, executing 
   3COM's configuration utility may result in the following error 
   condition:
   
    "12.03 The computer has a memory problem and needs to be 
   serviced."
   
   This issue affects the following systems: 501749, 501772, 501774, 
   501777, 501814, and 501815.    

 
BACKGROUND 
 
   The 3C509B adapter is an ISA adapter that can be configured as an 
   ISA or EISA adapter. Since the adapter has this capability, the 
   configuration/diagnostics utility must be able to determine if 
   the board is configured correctly when it is installed in a ISA 
   slot. 
   
   The error condition occurs when the utility performs a word read 
   at address FC80. The Adaptec 2940 adapter has reserved that 
   address location and puts up an error flag whenever an unknown 
   entity comes in contact with the address. Adaptec puts up the 
   flag because they want to protect the BIOS on the 2940 adapter 
   from being manipulated by foreign entities. The error flag is 
   passed to the computer system and the system generates a memory 
   error condition.    

 
ACTION 
 
   When configuring the 3COM adapter, remove the Adaptec 2940 
   adapter from the system.    

 
NOTES 
 
   This problem only exists when the 3COM and Adaptec adapters are 
   installed in the computer at the same time, and the 3COM 
   configuration utility is being executed. 
   
   No problems exist after the 3COM adapter has been configured and 
   the Adaptec adapter has been reinstalled in the computer.    

 
TAN 001016RC 
 
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