6 replies to this topic

[Atari-Jess]

Yes, I managed to build one a couple days ago (I wanted to be sure it was perfectly working before I announced it)

All in all it cost me the following:

$4.00 PCB
$0.33 1489 IC
$0.20 14 pin socket
$0.70 worth of pre-cut wire
$0.99 tantalum capacitor
$0.25 worth of solder
$0.99 DB 9 female connector
----------------------------
TOTAL: ~$8.60 with tax.

Of course I now have a lot of parts left over because I had to buy in modest bulk.
It works like a charm and I didn't need the resistor or the diodes (which I bought and later removed)

It just didn't want to work while it was in there. Who knows why.

The trip to the electronics store didn't cost me anything, since I buy a bus pass every week.

I am very happy that I finally have an SIO2PC cable after wanting one for so long, but it took until now for me to finally have one.

Apologies to Metalguy66 because I was planning on getting one from him, but I am somewhat electronically inclined...

Edited by Atari-Jess, Mon Mar 27, 2006 5:10 AM.

[Rybags]

Nice price on the IC.

From what I've read before (and experienced in my first APE interface), the diode and resistor can sometimes cause problems.

It took me some time playing about with my first one, and I think I did away with the resistor too.

There are different flavours of the 1489, and sometimes they can make a difference too.

But, my second effort, I built into my 130XE (to the original specs) with it's own DB9 port, and it happily coexists with a 1050 on the SIO port.

As always, I would recommend an APE interface to anybody using a real 8-bitter. Keep your 1050 boxed away for nostalgia and emergency use only.

[MEtalGuy66]

Rybags, on Mon Mar 27, 2006 5:15 AM, said:

Nice price on the IC.

From what I've read before (and experienced in my first APE interface), the diode and resistor can sometimes cause problems.

It took me some time playing about with my first one, and I think I did away with the resistor too.

There are different flavours of the 1489, and sometimes they can make a difference too.

But, my second effort, I built into my 130XE (to the original specs) with it's own DB9 port, and it happily coexists with a 1050 on the SIO port.

As always, I would recommend an APE interface to anybody using a real 8-bitter. Keep your 1050 boxed away for nostalgia and emergency use only.

You only need the diode if you want to use it at the same time with REal atari disk drives. The resistor may or may not be needed depending on the exact tolerance of the 1489 you used. And you dont need the capacitor either, its just there for decoupling purposes.

If you had a diode that caused the interface not to work, its because you had the wrong diode. You need one with a forward voltage drop of about half a volt or less.

[Atari-Jess]

As far as the diode, I chose a 1N4148

When I had everything in there, it partially worked. When I removed the cap, it didn't work at all, when I removed everything but returned the cap, it worked again.

[MEtalGuy66]

Atari-Jess, on Mon Mar 27, 2006 10:22 AM, said:

As far as the diode, I chose a 1N4148

When I had everything in there, it partially worked. When I removed the cap, it didn't work at all, when I removed everything but returned the cap, it worked again.

Well I dont know who's "design" you built, but in all the 1489 based SIO2PCs Ive seen, the cap simply goes from hot to ground. Which means that when everything is plugged up, and the the circuit is operating, its doing nothing.

Another possibiity of course, where the diode is concerned is that you had it backwards. I assume you'd know if you made this sort of trivial mistake, since you are electronically inclined.


But the main thing is that it works. If it works, then who cares, right? If you ever notice it hanging in the middle of long transfers, or getting errors, Id go back and re-evaluate your design, but as long as it functions trouble-free then why mess with it?

[Atari-Jess]

MEtalGuy66, on Mon Mar 27, 2006 2:39 PM, said:

since you are electronically inclined.

Again, somewhat I don't want to be saying im all that when I'm not. I can follow diagrams and solder somewhat decently and I know what parts do what. But I'm by no means an Electronics Engineer!

MEtalGuy66, on Mon Mar 27, 2006 2:39 PM, said:

but as long as it functions trouble-free then why mess with it?

True that

[Rybags]

Some people report problems with cables, but all I'm using is about 3 feet of ribbon cable with clip-on sockets, and it works fine.