VME bus trap ignored

[Chris Johns]

On 6/08/10 1:49 AM, Wolfgang Rostek wrote:
> Hi all,
>
> I'm doing some tests accessing VME bus addresses.
>
> I wonder that an invalid address is somehow tolerated by the Ada/RTEMS
> program but shows a correct trap using dBUG. No Ada exception handler
> seems to get invoked. Is it ok for the program to continue that way?

This depends on the requirements of your system. I would like to handle 
the exception and see what is the cause.

I suspect something in the RTEMS driver is (or is not) initializing 
something in the system controller that manages this part of the bus. It 
could be masking an interrupt or exception or turning the bus timer off. 
The dBug set up allows the exception to occur. I suspect the bus timer 
setup because of the dBug message about a timeout.

Chris

>
> The second assignment 'abcd' I can verify in RAM after restart. (the
> Memory_Address
> function is working for the whole address range)
>
> ----------------------------------------------------------------------------------------
>
> tip675_dummy : UNSIGNED_16 := 16#fedc#;
> for tip675_dummy'Address use Memory_Address(16#a0000000#);
>
> tip675_dummy2 : UNSIGNED_16 := 16#abcd#;
> for tip675_dummy2'Address use Memory_Address(16#40000000#);
>
> ----------------------------------------------------------------------------------------
>
>
> dBUG> md.l a0000000
> md.l a0000000
> A0000000: FF
>
> VME Bus Time Out
>
> PC: F0001474 SR: 2004 [t.Sm.000...xnZvc]
> An: FE000000 F001F830 F001F848 F001F7DD F001F830 CBF5F311 F001F7CC F001F7A8
> Dn: 00000000 00008600 00000046 FFFFFF00 00000000 00000008 00000008 00000046
> F0001474: 0801 0002 BTST #0x02,D1
> dBUG>
>
> Wolfgang Rostek
>
> Phone: +49 (89) 92 16-2183
> Fax: +49 (89) 92 16-162183
> wolfgang.rostek at esg.de
>
>
>
> _______________________________________________
> rtems-users mailing list
> rtems-users at rtems.org
> http://www.rtems.org/mailman/listinfo/rtems-users