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SIO2PC cable advice

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Can anyone tell me if I'll damage my 130xe if I build the cable at the top of this site: http://ftp.pigwa.net/stuff/collections/atari_forever/Extension/Sio2PC/The%20SIO2PC%20interface.htm and exclude the diode? I'm having trouble finding the diode that is specified in the diagram. I have a spare 1N5819 diode, would it be better to use that or no diode at all? Or is it recommended to just keep searching for the needed diode before building the cable?

 

I'm also wondering where I could install a LED in that diagram so I could see the activity while files are loading. Any idea?

 

Any help is greatly appreciated

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the diode is a generic signaling diode, the 1n914 is similar and about as common as you can get... 1n914/4148 should be in any electronics shop (even radio shack still sells them), worse case, go to a tv repair shop and ask them if you can buy one... many will just give you one...

 

sloopy.

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I have a spare 1N5819 diode, would it be better to use that or no diode at all?

 

The 1N5819 is a 1A, 40V, 70% @ 2.0MHz Schottky Barrier. Looks like it will do the job just fine.

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The diode is there, because the Max 232 has no "open collector" output.

And any diode will just do fine, although low barier voltage ones, like Shottky of Germanium will theoretically do better.

 

Not using the diode will disable the bus in a specific way.

It will no longer accept more than one device on the bus.

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I'm also wondering where I could install a LED in that diagram so I could see the activity while files are loading. Any idea?

 

Any help is greatly appreciated

 

Sorry this is kinda old topic but here we go anyway:

 

If you want to use the led as a POWER ON and ACTIVITY indicator, use the SIO COMMAND line (SIO7). SIO7 is pulled-hi (5 volts) when the computer is ON and there is no activity, and pulled-low when a command is sent to the disk drive. This way you catch all activity (read/write etc..)

 

Solder a 200 (or 300) ohm resistor directly from the SIO7 to the positive leg (anode) of the LED and solder the negative leg (cathode) of the LED to the nearest ground.

 

Ray

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If you want to use the led as a POWER ON and ACTIVITY indicator, use the SIO COMMAND line (SIO7). SIO7 is pulled-hi (5 volts) when the computer is ON and there is no activity, and pulled-low when a command is sent to the disk drive. This way you catch all activity (read/write etc..)

 

Solder a 200 (or 300) ohm resistor directly from the SIO7 to the positive leg (anode) of the LED and solder the negative leg (cathode) of the LED to the nearest ground.

Great info - thanks! This is excactly what I've been wanting to do for a long time - I just never got around to asking how. ;)

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If you want to use the led as a POWER ON and ACTIVITY indicator, use the SIO COMMAND line (SIO7). SIO7 is pulled-hi (5 volts) when the computer is ON and there is no activity, and pulled-low when a command is sent to the disk drive. This way you catch all activity (read/write etc..)

 

Solder a 200 (or 300) ohm resistor directly from the SIO7 to the positive leg (anode) of the LED and solder the negative leg (cathode) of the LED to the nearest ground.

Great info - thanks! This is excactly what I've been wanting to do for a long time - I just never got around to asking how. ;)

 

 

You're welcome fjc :)

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