What's that extra connector on a1200 1st revision mobo?

[Varthall]

(this question came after reading the A1200 schematics forum)

What's that connector on the first revision of the motherboard?

http://www.amiga-hardware.com/a1200mbr1abig.jpg

On the next revisions, my a1200 is among those, there are only soldering pads on the place.
It's located near the keyboard connector, aligned with the (full sized) clock connector. Does it have any purpose?

Varthall

[Varthall]

Matt_H wrote:
I think that's an early incarnation of the clockport. The A1200 was initially designed to ship with 1Mb CHIP, so the second Mb was to be connected through that interface. Of course it still accomodated a clock, and maybe some other stuff, too.

So does it mean that it's a second clockport? To avoid confusion, I'm referring to that stand-alone connector, which is very close to the keyboard one, not the standard clock port, which is located at the middle of the mobo and has also some empty soldering pads on later revisions. On my mobo I had to solder pins on these pads as they were needed by the melody1200 soundcard.

Varthall

[Varthall]

mepmepmep wrote:
Are we talking somehow about that strange plastic covered port, between the mouse port and the floppydrive? If not, I'm still curious; What the ... was the port i just mentioned supposed to be used for?

Just take a look at the picture mentioned before, its a connector similar to the one for ide drives.

That covered port you mention was simply a hole for expansions, and has been used by some SCSI add-ons for accelerator boards, like GVP and blizzard ones, and by the melody 1200 audio card. Maybe other cards used that port too.

@Doobrey:
Thanks for the info! So I guess that no one has ever tried to use that port for anything...

Varthall

[Varthall]

mepmepmep wrote:
To me, that brings up another question... probably just stupid.. but still.. Is there anyway to connect the A570 to an Amiga 1200?..

I would have posted this to an other thread, anyway... The answer is no, and it doesn't makes sense, too. It's cheaper and better to add an ide cdrom, you also get a faster drive this way.

 Probably not I suppose.. The A500 has one SCSI port and the 1200 has two IDE ports.. Is that correct?

The A570 has an add-on port for a scsi controller, and the A1200 has one ide port which supports two devices.

Varthall

[Varthall]

Dr_Righteous wrote:
Makes me wonder if anyone has tried sawing off CN1 and soldering in a header at CN1A... Might prove useful in a tight-space case mod  :-D

CN1? You mean the mouse port?

Varthall

[Varthall]

Doobrey wrote:
On some of the later A1200s, the motherboard was shorter and the mouse port was connected by a short ribbon cable.
 But you still need a case that takes the "full length" mobo if you want to stick an accelerator into it.

Yes, that's true. But it could be anyway useful to use those CN1A pads to add a clone of the mouse port, this way you could have both the mouse and a second joystick connected

Varthall