I think you just burned the SCSI chip on the A2091.
A friend is selling some of them in this very forum. Do a search for WD33C93.
Also never connect two boards if you don't know about 'em.
Or better buy another type of SCSI controller. A2091 is too slow and rubbish, anyway. Grab a GVP SCSI+ or SCSI+8 for a little more than the sluggish 2091 if you can afford it.
