Parent

IBM 5170 Fixed Disk and Diskette Drive Adapter -
Jumper Information



First generation
Second generation
Notes
Bug




First generation


Jumper Photo    Settings
E1 / E2 / E3 aaa  Option 1:  Jumper E2 to E3.  Floppy controller portion of adapter at primary address range starting 3F0h     <-------- DEFAULT SETTING

 Option 2:  Jumper E1 to E2.  Floppy controller portion of adapter at secondary address range starting 370h
E4 / E5 / E6 aaa  Option 1:  Jumper E5 to E6.  Hard disk controller portion of adapter at primary address range starting 1F0h     <-------- DEFAULT SETTING

 Option 2:  Jumper E4 to E5.  Hard disk controller portion of adapter at secondary address range starting 170h
E7 / E8    Factory jumper - do not remove
E11 / E12    Factory jumper - do not remove





Second generation


Jumper Photo    Settings
E1 / E2 / E3 aaa  Option 1:  Jumper E2 to E3.  Floppy controller portion of adapter at primary address range starting 3F0h     <-------- DEFAULT SETTING

 Option 2:  Jumper E1 to E2.  Floppy controller portion of adapter at secondary address range starting 370h
E4 / E5 / E6 aaa  Option 1:  Jumper E5 to E6.  Hard disk controller portion of adapter at primary address range starting 1F0h     <-------- DEFAULT SETTING

 Option 2:  Jumper E4 to E5.  Hard disk controller portion of adapter at secondary address range starting 170h





Notes

The IBM BIOS on the 5170 motherboard is programmed expecting the floppy controller portion and hard disk controller portion of the adapter to be at the primary addresses.

Selecting the secondary address range for the floppy controller portion will make that portion 'invisible' to the IBM 5170 BIOS.  The portion is still there, but the IBM 5170 BIOS will not look for it at the secondary address range.  Similar thing for the hard disk controller portion.




Bug

The following bug only happens when the hard disk controller portion of the adapter, first or second generation adapter, is changed to the secondary address range.
For that reason, very few people will experience it.

Symptom

Basically, you cannot boot from a floppy.
The sequence is:

1. Insert a boot floppy.
2. Power on 5170.
3. If the 5170's SETUP configuration is still configured for a hard drive, you will see a 1782 error (expected because no HDD controller at the primary address) - press F1 key.
4. Some floppy drive activity.
5. You will see a 601 error.
6. Boots to BASIC.

Comment

It is interesting that changing a jumper for the hard drive functionality of the adapter affects the floppy drive functionality.

It is not a case of getting the jumpers confused, because changing the floppy jumper results in no floppy drive activity whatsoever.

Investigation

Swapping out the IBM 5170 BIOS for the Award one at here gets around the problem - boots from the floppy drive.
That suggests the presence of a bug in the IBM 5170 BIOS.