ssd@sugar.UUCP (Scott Denham) (12/01/87)
(Repeat of an earlier plea for help)
I constructed a simple motor latch to interface a Tandon TM-100-2A drive
to my A1000, largely for the purpose of getting files from my Amiga to
a rather interesting graphics device at work through a rather un-
interesting 'blue' box. My problem is that since upgrading to a B2000
(4.2 rev) the drive no longer wants to work as a 'PC' drive, though its's
fine as a 40-track Amiga device. The symptoms are 'root directory full'
from PCcopy and 'error -4' from PCformat. Oddly enough the drive still
works fine in both modes on the old 1000. Can anyone shed any light on
what 'error -4' might mean, what differences might exist between the
1000 and 2000 implementations of the external disk interface, and
whether or not such a latch circuit needs any additonal 'tweeks' to
operate on the 2000 ??
Scott Denhamgrr@cbmvax.UUCP (George Robbins) (12/03/87)
In article <1151@sugar.UUCP> ssd@sugar.UUCP (Scott Denham) writes: > > interesting 'blue' box. My problem is that since upgrading to a B2000 > (4.2 rev) the drive no longer wants to work as a 'PC' drive, though its's > fine as a 40-track Amiga device. The symptoms are 'root directory full' > from PCcopy and 'error -4' from PCformat. Oddly enough the drive still > works fine in both modes on the old 1000. Can anyone shed any light on > what 'error -4' might mean, what differences might exist between the > 1000 and 2000 implementations of the external disk interface, and > whether or not such a latch circuit needs any additonal 'tweeks' to > operate on the 2000 ?? You might want to make sure that your drive doesn't have any heavy-duty 180 or 220 ohm terminating resistor packs. The A1020 drive is specified to use 1K terminators to avoid overloading the driver circuitry. The A1000 used discrete TTL buffers to drive the floppy signals, whereas the A500 and A2000 use a modified 8520 with high-current outputs to drive some of the signals, and a TTL buffer only on the signals that come from Paula via Gary. -- George Robbins - now working for, uucp: {uunet|ihnp4|rutgers}!cbmvax!grr but no way officially representing arpa: cbmvax!grr@uunet.uu.net Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)