[comp.sys.ibm.pc.hardware] NEC hard disk jumper info wanted

cur022%cluster@ukc.ac.uk (Bob Eager) (03/25/91)

I have just replaced a 20MB NEC hard disk with a 42MB one, in an XT clone.
No problems so far.
 
I want to put the old disk in as a second drive. However, neither disk has
any info about drive selection jumpering or termination resistors. Can
anyone help? The control cable (the wide one) does NOT have a twist in it,
so I need to do two things: alter the 20MB drive to be drive 1 instead of
drive 0; and remove the terminating resistor on one of the drives (I can
always make sure that drive is at the end of the cable).
 
The 20MB drive is an NEC D5126; it has a block of 8 switches marked DS;
switch 1 is set to ON at present and all others are OFF. I have tried some
obvious combinations. It has another 8 switch block marked T RES; all of
these switches are ON, so I guess if I turned them all OFF the terminating
resistor would be disconnected?
 
The 42MB drive is an NEC D3142; it has a block of 8 switches and another
block of 4 switches; neither appear to be marked.
 
The controller is a Western Digital WD1002A-WX1 with a SuperBIOS, version
62-000094-032.
 
Help please!
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Bob Eager                | University of Kent at Canterbury
                         | +44 227 764000 ext 7589
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