Closed Solution for Ratte switch on A4000 with socketed CIA

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timmie

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Currently migrating from one A4000 PCB to another one. However the target PCB has the CIA socketed where I need to put the Ratte CIA adapter. I.e. that's a no go. Has somebody got a solution? Is there a standard sort of riser component I can put in the socket, then put the CIA chip on there and have room to slide the CIA adapter over it? Or anything else that works.

Thanks!!
 
I'm facing the same problem with my A4000T where I socketed both CIAs.

The required signals are also present externally on the serial port. But that would mean a bulky DSub connector and routing a cable from the outside to the inside of the case.

The A4000T however, is modular, so I can get the signal from the pin header for the ports module...
 
Thanks, the serial port may be an, albeit bulky, option, but somebody then needs to make me a cable :)

The sub par solution would be to put a manual switch on the pins for the jumper I guess. Can I operate such a switch while the Amiga is running?

I still hope to be able to use the "auto" part of my Ratte switch, preferably with a more elegant solution :)
 
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Yes, the three way (Amiga-Auto-RTG) switch works while running the Amiga. In fact, it does exactly the same as the Auto mode.

There's another internal solution. You can solder a thin wire to pin 8 of U305 (1489) in the A4000D to get the required CTS signal.
In addition, you need 5V and GND, which are available in a lot of locations, like all Zorro slots, the power connector, on each of the active components, etc. You can tap these from the 1489 too, if you want.

If you don't want to solder, look for "SOIC14 test clip" on your favourite selling platform.
 
So have this testclip "grab" U305 and take pin 7 for GND, pin 8 for the signal and pin 14 for 5V?
 
So have this testclip "grab" U305 and take pin 7 for GND, pin 8 for the signal and pin 14 for 5V?
Yes, I guess this should work. I don't know about the long time stability of the test clips though... But it might be worth a try.
 
It just feels like not the best solution with the test clip. I also don't have any (recent) soldering skills. That's something I wanted to pick up again in 2020, but I don't expect to gain significant experience quickly to work on a PCB. Just hope to be able to do some cable/connector repair stuff within a few months.

So for this topic I'll go for one of the following 2 solutions (or maybe both, if I want to switch to RTG only when running AOS4.1 classic):

- Serial connector giving me the same cable as the CIA adapter, which I can connect to the Ratte switch. If somebody is willing to build me one for a recent price I'm open for offers.
- Manual on-off-on switch, that's ideally round and fits through the keylock whole and looks nice enough, something ike this https://www.ikod.se/ratte-control-switch/, but I'll settle with a (nice looking) purely mechanical switch too. So same here, if somebody is willing to build me one for a recent price I'm open for offers.
 
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It just feels like not the best solution with the test clip. I also don't have any (recent) soldering skills. That's something I wanted to pick up again in 2020, but I don't expect to gain significant experience quickly to work on a PCB. Just hope to be able to do some cable/connector repair stuff within a few months.

So for this topic I'll go for one of the following 2 solutions (or maybe both, if I want to switch to RTG only when running AOS4.1 classic):

- Serial connector giving me the same cable as the CIA adapter, which I can connect to the Ratte switch. If somebody is willing to build me one for a recent price I'm open for offers.
- Manual on-off-on switch, that's ideally round and fits through the keylock whole and looks nice enough, something ike this https://www.ikod.se/ratte-control-switch/, but I'll settle with a (nice looking) purely mechanical switch too. So same here, if somebody is willing to build me one for a recent price I'm open for offers.
There's still another solution: You can use a signal from the parallel port (don't know which one atm, but could find out if you want).
In contrast to what I wrote earlier, I can't recommend using the serial port, because the RS232 standard allows voltages of up to 25 volts for any given signal. That's the reason for the 1488 and 1489 chips. They translate between TTL and those high level voltages.
Putting 25V in your Ratte Switch will kill it for sure.

Btw. soldering PCBs is much more easy than soldering cables. Just use a good, temperature regulated iron and always apply flux. Do your Jedi training on some old PC mainboard and you will be a pro in no time!
 
OK, maybe I'll just stick with a manual switch for now and do the soldering myself when I'm confident enough. Thx!

Someone has the exact dimensions of the keylock whole of the front panel of the A4000D, so I can go shop for a nice looking (mechanic) round on-off-on switch?
 
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