28 Feb
2003
28 Feb
'03
3:39 p.m.
On Fri, 28 Feb 2003, Tony Duell wrote:
Maybe this is part of the problem. Neither drive has a terminator on it.
Are you sure? It normally goes in a DIL socket near the interface cable.
Is there a totally empty socket on both drives?
They are separate resistors without interconnection.
- don
I haven't seen anything in xtrs that lets me use a physical disk, only
disk images. Does anyone know if I'm mistaken and xtrs will read disks?
I have the source of an old version on this machine. I can't run it,
because I don't run X, of course, but a quick grep shows a number of
FDRAWCMD ioctl()s in trs_disk.c. Which implies to me that it's accessing
the PC disk controller at a low level, to read a non-native (for the PC)
disk format, presumably a real TRS-80 disk.
-tony
On Thu, 27 Feb
2003, Tony Duell wrote:
Sorry, guess I should have been more specific. The (drive that was
0:) drive spins, and the LED comes on, but the machine still says "Cass?".
OK...
What test equipment do you have available? Multimeter? Logic probe? Logic
analyser? 'scope?
I can probably suggest signals to look at to find out exactly what's
going on...
Aparently, the Drive 0: is bad. Replacing it with the 1: or an
Does the spindle motor run on this drive when you try to boot from it?
Does the LED come on? The other drive (which I had replaced it with)
attempts to read from the
disk, and either displays "Diskette?" or nothing if there's no disk in the
drive or a disk, respectively.
Of course at this point you don't _know_ that the disk controller or CPU
boards are working correctly...
IBM-branded Tandon drive from an IBM 5150 PC, it seems to try to boot from
What have you done about the termination resistor pack (the 'odd coloured
IC' on the drive logic board)? The machine will not do the right things
if the last drive on the cable is not terminated. What resistance is it? I could probably try
making one out of spare
150 Ohms, but I can't remember if the resistors are separate or if they
have a common connection to the highest-numbered pin on the package. I
think the former. I would like
to try to make an image from the disks I have, is there a
program that works under Linux with a standard floppy disk controller to
read disks and spit out .dsk files?
I've not written one yet (although it would not be hard to do). However,
I belevie xtrs can do this (BACKUP from a physical disk to an emulated
one). Since I don't run X, I can't be sure, though.