DrCharles
Experienced Member
In another thread, I chronicled my adventure getting a 3.5" floppy drive hooked up to my PDP-11/23+.
It now looks to the system (RT-11 5.04 and TSX+ 6.50) like an RX33 with nearly 2400 blocks. So far so good.
I had a 720K disk mixed in there, and when I put it in the PDP-11, FORMAT balked and warned me it was an RX50 disk. So the controller can "tell".
I can format DS/HD disks on the PDP-11, and read and write to them... but when I put them in the WinXP box running PUTR, they won't even read the directory. PUTR is correctly set up for RX33 type, RT11 filesystem.
In fact, most of the used disks won't even format on the PC, let alone read/write. OK, so they're old. Found some more disks (a new-old-stock box of Memorex DS/HD) and they will format on the PC or on the PDP-11, but they can only be formatted, read or written by the hardware that did the format!
Figured it might be drive head misalignment since this hardware is all old. I tried another 3.5" drive in the PC after cleaning the heads and it behaves exactly the same way.
What's really strange is that just ONE used Verbatim DS/HD disk can be read and written between systems, just like they all should.
Any ideas what's going on here? Do I need two new drives? Or just go back to RX50 5.25" drives?
It now looks to the system (RT-11 5.04 and TSX+ 6.50) like an RX33 with nearly 2400 blocks. So far so good.
I had a 720K disk mixed in there, and when I put it in the PDP-11, FORMAT balked and warned me it was an RX50 disk. So the controller can "tell".
I can format DS/HD disks on the PDP-11, and read and write to them... but when I put them in the WinXP box running PUTR, they won't even read the directory. PUTR is correctly set up for RX33 type, RT11 filesystem.
In fact, most of the used disks won't even format on the PC, let alone read/write. OK, so they're old. Found some more disks (a new-old-stock box of Memorex DS/HD) and they will format on the PC or on the PDP-11, but they can only be formatted, read or written by the hardware that did the format!
Figured it might be drive head misalignment since this hardware is all old. I tried another 3.5" drive in the PC after cleaning the heads and it behaves exactly the same way.
What's really strange is that just ONE used Verbatim DS/HD disk can be read and written between systems, just like they all should.
Any ideas what's going on here? Do I need two new drives? Or just go back to RX50 5.25" drives?