Re: devLib, locationProbe routine

[Andrew Johnson <anj@mail.ast.cam.ac.uk>]

On Wed, 26 Oct 1994 08:36:30 -0600 Marty Kraimer wrote:

> > From anj@mail.ast.cam.ac.uk Wed Oct 26 08:21 CDT 1994
> > 
> > Am I right in thinking that the routine  locationProbe  in devlib returns 
> > SUCCESS to indicate that the given address does *not* respond to VME 
accesses of 
> > any size?  I presume the aim here is to indicate that this area of the 
memory 
> > map is currently not used.
> 
> No it returns success (0) only if something responds AND no one else has
> requested something from the rage of addresses requested. Thus ALL non 0
> returns values are errors. 

That's not what my version (3.11.4) does - has anyone actually tested it?

->devAddressMap
value = 0 = 0x0
->locationProbe 1, 0x200000
value = 34144265 = 0x2090009
->*0xf0200000
_rsrv_free_clientQ + 0xef24fabc = 0xf0200000: value = -14204673 = 0xff2740ff = 
_rsrv_free_clientQ + 0xfe2c3bbb
->locationProbe 2,0x80000000
value = 0 = 0x0
->*0x80000000
0x80000000: value = 
Bus Error
Program Counter: 0x00053e1a
Status Register: 0x3000
Access Address : 0x80000000

(I have a card at A24:0x200000, none at A32:0x80000000, no addresses registered)

I presume from your description that a driver should call  locationProbe  before 
calling  devRegisterAddress  which is probably reasonable (although it means 
that devLib has to use  sysBusToLocalAdrs  twice and there is more work needed 
in converting a driver).

- Andrew

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