24 Mar
2010
24 Mar
'10
1:13 a.m.
On 23 Mar 2010 at 23:59, Pete Turnbull wrote:
Interesting -- I'd not come across that, so
I've just learned
something new. Any easy ones I should look out for? I think I may
have a use for that idea.
Some Samsung and Mitsubishi drives document "1.6MB support" jumpers,
so you'd want that.
But if you're like me, I have buckets full of Teac FD235-HF and -HG
drives, particularly those with a drive select jumper and nothing
else. On these, find the pads labeled S3 and S4. You'll find a 0-ohm
SMT resistor installed on S4 and an ohmmeter will show that it's
connected to the +5 line. If you check the unpopulated S3 pads next
to it (usually), you'll find one is connected to one of the S4 pads
and the other is connected to pin 2 of the drive interface header.
The usual way of adapting these is to replace the S4 jumper with a 1K
SMT resistor and jumper the S3 pads with a 0-ohm resistor. This
gives the spindle speed control to pin 2, which is an option if your
system uses pin 2 as a density select pin.
I usually remove the S4 jumper completely and run a wire between the
pad that's not connected to +5 and ground. This hard-configures the
360RPM spindle speed without regard to pin 2.
--Chuck