Subject: RE: KA675/KA680 differences
To: 'Michael Kukat' <>
From: Carlini, Antonio <>
List: port-vax
Date: 01/13/2001 00:07:36
	> So the speed might be not that different? According to the HW
reference on
	>, KA675 (4000/400) is Mariah based and rated 16
VUPs, while the
	> KA680 is rated 32 VUPs. But ok, i'll see. It just came up in
networked single
	> user mode. I'll compile a kernel now, put my KFQSA in it, and have
fun with
	> a cool new machine... at least i hope so :)

	I'm not near my notes (well, I am but the machine is switched off 
	and it's late ! ) but from memory the KA680 was the first NVAX VAX
	The KA675 was presumably built to fill a gap in the performance
	range - this was done by disabling the VIC. I suppose theoretically
	this would have allowed otherwise useless NVAX chips (i.e.
	those where everything worked except the VIC) to be used.
	I doubt that this would have been worthwhile. (This was done
	in other cases though - the original DECnis MPC used culled
	SOC chips: i.e. those where the FPU had failed and at least
	five of the six (or 8??) cache banks worked).

	> I only have KA660 and KA680 here. KA660 helped me a lot for this
port, and
	> KA680 still waits for support... I think, i'm _extremely_ near.
Maybe Stefan
	> will get something for the TM the next days, if everything works
like i want
	> it to...

	> Ok, the 4k60 and 3100m80 is correct in this case. And things math
in this
	> case as i got the same strange errors, and the same interrupt
vectors for
	> memory (0x54 and 0x60).

	> 680 is still missing. I encountered strange problems about... half
a year ago,
	> but now i see new light, if the 680 is that near to the 675. I was
	> the experimental hardware for this, and the KA53 i have here is
too much
	> different from the KA680 due to the dz at ibus instead of

	I've got tech manuals for most of the above kicking around somewhere
	so if you need descriptions of the interrupt structure just ask (I'm
	such details are in the manuals I have ... ). It may take me a few
days to
	get to the docs though.

	If you have the EK-KA680-TM then you should be able to get any and
	of KA675, KA680, KA69x working since they are all the same with 
	just a few *minor* differences (CPU cycle times, cache size, VIC

	The basic design is (AFAIK) identical.