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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Orjan on July 25, 2004, 09:04:04 PM

Title: How do I connect a LED to a CD-ROM?
Post by: Orjan on July 25, 2004, 09:04:04 PM

I am thinking about putting a slimline CD-ROM into my A1200, and I thought it would be cool to have an extra LED to show me when the CD-ROM is working or not... But I don´t know how to connect it.. I have only seen the Catweasel MkII S-class to have connectors for external LEDs, so I guess I have to hack a little...

Does one of the pins from the CD-ROM interface carry the LED indication, so I can connect it directly to the connector? Or perhaps you have a better solution for me?

Title: Re: How do I connect a LED to a CD-ROM?
Post by: Brian on July 25, 2004, 10:23:32 PM

Well.. the HD led should light up anyway so I guess it could be a HD/CD indicator. There are a few IDE splitters available that gives the option of adding a indication led for the second IDE chain. If you keep the HD on the first IDE chain and the CD on the second and then that led would do it I think. While you're at it with adding leds to the machine you should concider adding a PCMCIA Activity led aswell (great for when you use a PCMCIA Ethernet card).

Title: Re: How do I connect a LED to a CD-ROM?
Post by: Orjan on July 26, 2004, 11:25:58 AM

Way ahead of you! :)

I intend to put a slimline CD-rom in my 1200, provide it with an extra LED, and do the PCMCIA LED "hack"... It´s gonna be so cool... :)

Anyway, if the IDE controller doesn´t have connectors for external LEDs, what can I do? I don´t want the HD LED on the 1200 to light up when the CD is working, I want a separate LED for it...

Title: Re: How do I connect a LED to a CD-ROM?
Post by: Brian on July 26, 2004, 01:07:35 PM

The splitter (controller) will have an external connector for a led if you want to cause the design of the hack show how to add that.

This page showing the hack (http://user.it.uu.se/~jesperw/se/amiga/4ide.shtml) is in swedish but I think you'll be able to use it anyway.

That led should only light up when the CD is in use but I don't know if the HD led will shine TOO at that time.

Title: Re: How do I connect a LED to a CD-ROM?
Post by: Orjan on July 26, 2004, 01:15:45 PM

Well, I am swedish, so everything made perfect sense... :)

So, it´s pin 39 controling whether the LED should be on or off? Can I just solder a cable to the back of the IDE connector and hook it up to a LED?

Title: Re: How do I connect a LED to a CD-ROM?
Post by: lorddef on July 26, 2004, 01:22:42 PM

I havent looked at the diagram and neither do I know much about IDE interfaces, but I would think you'd use the signal from pin 39 to switch a transistor which would light the led from another poersource, such as the 5v line.

Title: Re: How do I connect a LED to a CD-ROM?
Post by: Brian on July 26, 2004, 01:26:35 PM

@Orjan

I don't think that will work... you need to make the full device or you'll have the CD led light at the same time as the HD led all the time anyway so.

So as it's a realy simple hardware to make you should try it... ELFA will have all the bit's you need for peanuts.

Title: Re: How do I connect a LED to a CD-ROM?
Post by: Orjan on July 26, 2004, 01:35:57 PM

I don´t think I´m going to build the device, I am probably going to buy one from ggsdata.se...

But in the schematic it says:

Optional LED:

    +5V DC      o---[220ohm]---->|-----[39]
                               LED

Now, all I want to know is if I can connect a LED like this, by soldering a cable on the opposite side of the IDE controller I am going to buy? Or how should I connect it to the CD-ROM so it lights up when the CD is active?

Title: Re: How do I connect a LED to a CD-ROM?
Post by: Orjan on July 26, 2004, 01:41:32 PM

I don´t think I´m going to build the device, I am probably going to buy one from ggsdata.se...

But in the schematic it says:

Optional LED:

    +5V DC      o---[220ohm]---->|-----[39]
                               LED

Now, all I want to know is if I can connect a LED like this, by soldering a cable on the opposite side of the IDE controller I am going to buy? Or how should I connect it to the CD-ROM so it lights up when the CD is active?

Title: Re: How do I connect a LED to a CD-ROM?
Post by: Brian on July 26, 2004, 01:57:18 PM

The scematic say you should connect the led to the second IDE connector not the first as it will be if you solder it to the IDE controller. It would possibly work but would if so result in the led light up when the HD led light up so you'd have 2 leds flashing at the same time... so quite useless.