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Re: Code or SWI to read word of logical memory?

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"Theo Markettos" <theom+news@chiark.greenend.org.uk> wrote in message 
news:8Oh*WXaEt@news.chiark.greenend.org.uk...
> neil f <news@anf.nildram.co.uk> wrote:
>> Whoops. Just noticed I'd left the MOV PC, R14 off the end. Now it does 
>> what
>> I'd expect - i.e. nothing.
>>
>> Peter van der Vos kindly wrote and posted a very simple memory access
>> module in response to my request for GPIO access routines on the ROOL
>> forum.  Unfortunately that module doesn't allow wide-ranging access of 
>> the
>> kind I need now, so I thought I'd try to write something simple myself.
>
> You can write a very simple module like this yourself.  Just have a
> barebones module with a few SWIs.  I once wrote a module called SVCUtils
> with the following SWIs:
>
> SVC_LDR
> SVC_LDRB
> SVC_STR
> SVC_STRB
>
> Each SWI handler just calls the appropriate instruction then returns, eg:
> .SVC_STR
> STR r0,[r1]
> MOV pc,r14
>
> Then you can call it thus:
> SYS "SVC_STR",&45,&03010FE0
> equivalent to !&03010FE0=&45
>
> It isn't 32 bit and I don't have the source to hand, but it shouldn't take
> long to write something similar, or modify Peter's version.
>
> Theo

I downloaded SVCUtils module from your website, Theo, and it seems to run OK 
on the XM. I've loaded and saved a few sample GPIO registers without 
problems showing up. Are you sure it isn't 32-bit compatible? It seems to 
have the 32-bit flags word present. 

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Thread

Code or SWI to read word of logical memory? "neil f" <news@anf.nildram.co.uk> - 2011-05-27 09:34 +0100
  Re: Code or SWI to read word of logical memory? Theo Markettos <theom+news@chiark.greenend.org.uk> - 2011-05-27 11:42 +0100
    Re: Code or SWI to read word of logical memory? "neil f" <news@anf.nildram.co.uk> - 2011-05-27 13:29 +0100
      Re: Code or SWI to read word of logical memory? "neil f" <news@anf.nildram.co.uk> - 2011-05-27 13:47 +0100
        Re: Code or SWI to read word of logical memory? "neil f" <news@anf.nildram.co.uk> - 2011-05-27 14:36 +0100
          Re: Code or SWI to read word of logical memory? Theo Markettos <theom+news@chiark.greenend.org.uk> - 2011-05-28 00:20 +0100
            Re: Code or SWI to read word of logical memory? "neil f" <news@anf.nildram.co.uk> - 2011-05-29 21:31 +0100
              Re: Code or SWI to read word of logical memory? Theo Markettos <theom+news@chiark.greenend.org.uk> - 2011-05-29 23:40 +0100
            Re: Code or SWI to read word of logical memory? Jeremy Nicoll - news posts <jn.nntp.scrap007@wingsandbeaks.org.uk> - 2011-06-01 02:07 +0100
              Re: Code or SWI to read word of logical memory? Rick Murray <heyrickmail-usenet@yahoo.co.uk> - 2011-06-01 04:24 +0200
          Re: Code or SWI to read word of logical memory? Tank <webmaster@tankstage.co.uk> - 2011-05-28 06:54 +0100
            Re: Code or SWI to read word of logical memory? "neil f" <news@anf.nildram.co.uk> - 2011-05-28 22:36 +0100
              Re: Code or SWI to read word of logical memory? Tank <webmaster@tankstage.co.uk> - 2011-05-29 08:38 +0100

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