On 11/30/19 7:16 PM, Fred Cisin via cctalk wrote: > On Sat, 30 Nov 2019, Bill Gunshannon via cctalk wrote: >> I'll start with the simple and funny one. If i run FORMAT >> it formats all 80 tracks. :-) Seems like the definition >> for an 8" disk as selected in the config menu is just plain >> wrong. Of course, once it formats all 80 :-) tracks any >> attempt to access it, like a DIR, just returns "sector not >> found". > > A lot could depend on how the software is interpreting the FDC return > codes. > > In the case of PC BIOS (765), error code number 4) that would mean that > it did format; it sees sectors, but not the one that you asked for. > That may be that the format command setup and the read are in > disagreement on sector numbers, and/or sector size. > > It could also happen if it ended up on the wrong track. (then the C > field of the CHRN of the sector doesn't match the C field of the CHRN > requested) > Even a non-functional stepper could do that. Be well aware thet > "VERIFY" checks whether there are READABLE sectors, not whether they > have correct content. If you want RELIABLE code, include a READ after > WRITE, rather than rely on the FDC "VERIFY". > A non-functional WRITE (including FORMAT) will VERIFY just fine, but > leave behind whatever had been on the track before, rather than what you > though that you had put there. > > PC FDC returns error code 2 for not seeing address mark. However, > MS-DOS goes through a short list of codes that it knows, and then falls > through to "error, but none of the above" and says "General Failure" (I > can't help but think that that was one of the brass in VietNam)
I think you missed something. This is a P112 SBC not a PC. I watch the head step from track to track until it runs into the stop after passing the last real track. I have a dbit 8" adapter and it displays the track count and I watch it go from 0 to 79. I am assuming the problem is that wherever the disk parameters are being stored on the P112 they are wrong for 8" disks. bill
