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Re: device matching at mainbus

On Wed, 16 Jan 2013, Holm Tiffe wrote:
There are interrupt levels until 1F and each vector entry has 4 Bytes length
(longword). Int 0 has an offset 0 in the SCB. IPL 14 which is needed for my
console driver has the possible Offsets of 0xF8,0xFC and 0x100.
How is this meant from the rtVAX Manual that the SCN should have an Vector
of 0x2c0 and an IPL 14? The VAX standard lists the Offset above 100 as
Implementaion-dependant...wich says nothing at all.

I'm not sure what you're looking at (perhaps table 5-5 DEC Std 32?), but
IPL is really independent of the vector. There is no requirement that any
particular vector have any particular IPL.

For vectors F8 and FC, their talking about a standard console interface
using the internal registers you would get at using MTPR/MFPR. You don't
have such a console, so they are not relevant.

Vectors 100-13C are typically used for IPL 14 vectors by a bus adapter
like the UNIBUS adapter. This has nothing to do with your hardware.

If your hardware implements a console interrupt, it will probably do
so according to the VAXeln requirements, which would be an IPL 14
interrupt with vector 0x2c0.
roger ivie

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