formatting m2351 Eagle on Interphase 4200

[Anthony A. Datri]

I've got an Interphase 4200 SMD controller stuck into a 3/180, and am
trying to format an Eagle with little success.  I've tried a variety of
paramters and jumper settings, but always end up with

write: I/O error
error 29: sector not found
write: I/O error
error 29: sector not found
write: I/O error
error 29: sector not found

When doing a "mapformat" in ipdiag.  Once I got it so that it only gave
the error once, and was able to do a "format" of the whole drive without
errors, but "flawmap" didn't seem to comprehend the spare sectors, and
tried to map every track with an error, which it couldn't do with much
sucess.

Any ideas?  I really want to stop relying on xy450's.