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Conference hydra::amiga_v1

Title:AMIGA NOTES
Notice:Join us in the *NEW* conference - HYDRA::AMIGA_V2
Moderator:HYDRA::MOORE
Created:Sat Apr 26 1986
Last Modified:Wed Feb 05 1992
Last Successful Update:Fri Jun 06 1997
Number of topics:5378
Total number of notes:38326

3879.0. "2090a and Hard disk led" by LUCCIO::RONCAGLIONI (Luca, IW2BQB in Milan -ITALY-) Tue Jun 26 1990 21:14

Hi!

I've an A2000 with 2090a and a SCSI disk. I've connected the Hard Disk's led 
but it is always lit and doesn't flicker with the HD access. It is 
connected on the 2090a.
It does work properly if I connect a ST506 HD.

Anyone is experienced in this? Any idea? What have I done wrong?

Thanks in advance. 
Luca
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3879.1short pulse (spike!)WJG::GUINEAUTue Jun 26 1990 23:0419
The 2090(a) should work fine with a SCSI hard disk - actually it will appear
as though the light doesn't blink at all!

I suspect you have the led cable connected incorrectly. There are 2 sets of
pins on the 2090(a) for led connection. They are located right next to
each other. Try moving the connector to the other set of pins.

Now the light will blink very slightly when the disk is acessed. This is 
because the 2090 only blinks the led for SCSI drives during actual DMA - which
is of very short duration, hence not enough energy to light the led.

If you'ld like, I can upload a schematic of a simple circuit I designed and
built which will stretch the LED pulse comming from from the 2090(a),
making the LED look great! The whole thing costs about $5.00 and 1 hour
of your time.

john

3879.2MQOFS::DESROSIERSLets procrastinate....tomorrowThu Jun 28 1990 17:4610
    Most drives have a set of pins on which you can connect a led, this is
    what I did when I installed a SCSI drive on my 2090a.  In fact I made
    another hole next to the green led and now I have two leds, one for
    each drive.  Another possibility is to use a bi-color led, one side
    driven from one drive and the other from the other drive, a guy in our
    group did just that and it quite a show to see the led glow green then
    red then orange (when both drives are active)
    
    Jean
     
3879.3Everbody shoulda have one...FROCKY::BALZERChristian Balzer DTN:785-1029Fri Jun 29 1990 07:129
Re: -1 (bicolor LED)

To the best of my knowledge, the HD-LED of the B2000 is a bicolor version,
at least mine is. 
I use the the green mode, since a red flickering at this particular location
has my subconcious crying "GURU"... ;-) 

<CB>

3879.4Ok for the schematicLUCCIO::RONCAGLIONILuca, IW2BQB in Milan -ITALY-Fri Jun 29 1990 16:397
Hi John! I'll check for the cable connection this weekend.

I'll be more than happy if you can upload the schematic you told in (.1).

Thanks!
Luca