Problem w/ older IBM 2.5" ide drives on A600/A1200

[Argus]

Here's a riddle I just thought I'd throw this out to the group.  I'm trying to install a couple of older IBM 2.5" drives in the A600 and A1200 that I have.  The drives are 1GB and 540MB and came out of working but old 486 IBM notebooks.  When I took them out they had special ribbon connectors that accessed the extra four pins on the far end of the harddrive pinout (i.e. 48 pins instead of 44).  To install in the A600/A1200s I tried used regular 44-pin 2-inch ide notebook cables but neither drive is recognized at all on either machine.  I know the ide headers work on both machines because another 1GB Hitachi drive I had works on both.  Any ideas?  fyi, there are no jumpers on the pcbs of either of the IBM drives.

[Argus]

Thanks.  Yes, the drives came out of old Thinkpads. I'll try shorting pins 45-46 or 47-48 as suggested.  First, I need to check to see if the A1200 internal ide is default master or slave (I think it's default is master).  I shall report back with results.

[Argus]

Well, I got the 1GB drive working but the 540MB looks like maybe it needs the low-level format trick.  Thanks for the help!