[ECOS] Questions about Interrupt and Handler?

[ECOS] Questions about Interrupt and Handler?

[MJLiu]

Dear Sir :

I am using eCos and ARM7TDMI, and if it isn't too much trouble, may I have
the following queries:

1. As we know, the relationship between exception type and its respective
vector address in ARM7TDMI is as follows:

    vector address        exception type
            0x00         Reset
            0x04         Undefined Instruction
            0x08         SWI
            0x0C              Prefetch Abort
            0x10         Data Abort
            0x14         Reserved
            0x18         IRQ
            0x1C         FIQ

And as we know, in eCos, there exist the mechanism of interrupts and
exceptions, and there are distinct spaces for exception and interrupt
vectors.

My question is that which exception vector addresses of ARM7TDMI are for
exception vectors in eCos, and which are for interrupt vectors in eCos?

2. I need to program exception and interrupt handlers for ARM7TDMI. So, are
there any source code examples for exception and interrupt handler
installation and manipulation?

3. Are there any detailed documents and source code examples for VSR
(vector service routine) manipulation?
    In eCos documents, it seems that they do not mention how to install
VSRs. Would someone tell me how to make it?

Would someone give me the answers for the questions above.

Many thanks in advance!!


Regards,


Liu Ming-Jun

Re: [ECOS] Questions about Interrupt and Handler?

[Jonathan Larmour]

MJLiu@mxic.com.tw wrote:
> 
> 1. As we know, the relationship between exception type and its respective
> vector address in ARM7TDMI is as follows:
> 
>     vector address        exception type
>             0x00         Reset
>             0x04         Undefined Instruction
>             0x08         SWI
>             0x0C              Prefetch Abort
>             0x10         Data Abort
>             0x14         Reserved
>             0x18         IRQ
>             0x1C         FIQ
> 
> And as we know, in eCos, there exist the mechanism of interrupts and
> exceptions, and there are distinct spaces for exception and interrupt
> vectors.
> 
> My question is that which exception vector addresses of ARM7TDMI are for
> exception vectors in eCos, and which are for interrupt vectors in eCos?

All are exceptions except IRQ and FIQ which are interrupts (despite the
indication otherwise in hal/arm/arch/current/inclued/hal_intr.h). Although
Reset isn't really an exception anyway.

> 2. I need to program exception and interrupt handlers for ARM7TDMI. So, are
> there any source code examples for exception and interrupt handler
> installation and manipulation?

Most device drivers do.
 
> 3. Are there any detailed documents and source code examples for VSR
> (vector service routine) manipulation?
>     In eCos documents, it seems that they do not mention how to install
> VSRs. Would someone tell me how to make it?

http://sources.redhat.com/ecos/docs-latest/ref/ecos-ref.9.html#pgfId=1023460

It's an assembler routine. Examples are the default routines in vectors.S
in hal/arm/arch

Jifl
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Re: [ECOS] Questions about Interrupt and Handler?

[Gary Thomas]

On 17-Jul-2001 Jonathan Larmour wrote:
>> 3. Are there any detailed documents and source code examples for VSR
>> (vector service routine) manipulation?
>>     In eCos documents, it seems that they do not mention how to install
>> VSRs. Would someone tell me how to make it?
> 
> http://sources.redhat.com/ecos/docs-latest/ref/ecos-ref.9.html#pgfId=1023460
> 
> It's an assembler routine. Examples are the default routines in vectors.S
> in hal/arm/arch

Another example is in hal/arm/edb7xxx/current/misc - look at the i2s_audio...
files.  This is a program which installs a VSR to handle the FIQ from the 
audio processor.

Re: [ECOS] Questions about Interrupt and Handler?

[Gary Thomas]

On 17-Jul-2001 Jonathan Larmour wrote:
>> 3. Are there any detailed documents and source code examples for VSR
>> (vector service routine) manipulation?
>>     In eCos documents, it seems that they do not mention how to install
>> VSRs. Would someone tell me how to make it?
> 

Another thing: it is a rare program indeed that needs to install it's
own VSR, especially on the ARM.  Most of the time all you'll need is to
install an interrupt handler (ISR/DSR).