topic Getting started with exceptions? in MPC5xxx

Getting started with exceptions?

bobgrimes — Fri, 14 Apr 2017 01:46:52 GMT

The MCP5744P is cool, but the docs are really confusing for someone jumping into the deep end... For me, I think the biggest problem is terminology; I've been working the embedded processing scene for many years, but until now, I have only encountered Power architecture in Xilinx Virtex4. This is the background I am coming from, so please understand that I understand the concepts here, but not the terminology; this is the cause of my confusion, I am sure. To be clear, below when I "quote" something, this is to indicate where I think I am confused by terminology, or specifics of the 5744P.

I am trying to develop "exception handlers" for various issues that may arise. A partial list I was given is this:

Critical Interrupt (IVOR0)
Machine Check (IVOR1)
Data Storage (IVOR2)
Instruction Storage (IVOR3)
Alignment (IVOR5)
Program (IVOR6)

Here are my problems that are causing great, personal grief, that I am 1000% positive many out there can help with!

Where the hell do I find documentation for these???
How do I associate a handler for these? I'm not looking for the basics of how one writes an ISR or the like. I just don't know the details of how you wire one up to the "exception". For example, using other architectures, how do I set an interrupt vector to point to an ISR to service the interrupt? How is it enabled?
In the interest of testing my handlers, how do I intentionally cause any/all of these?

To those in the know, my frustration lies in the fact that I know the information is out there, but the complexity and terminology differences between simpler (?) architectures (e.g. wicked old Intels, Coldfires, ARM) and this beast are killing my confidence!

Re: Getting started with exceptions?

petervlna — Mon, 17 Apr 2017 19:08:42 GMT

Hello Bob,

A1: You can find the documentation in core reference manual.MPC5744P contains 2x e200z425 core,

Here is link:http://cache.nxp.com/assets/documents/data/en/reference-manuals/e200z4RM.pdf?fsrch=1&sr=2&pageNum=1

Refer to chapter 5 Interrupts and Exceptions, specially to Table 5-3. Exceptions and Conditions.

A2: I am not sure if there is a guide document for it but we have posted a lot of examples including Exception, ISR and handlers here on community:

MPC5 software example list

A3:These details you can find in core reference manual in chapter 5.7 Interrupt Definitions.

Hope it helps,

Peter

Re: Getting started with exceptions?

bobgrimes — Sun, 23 Apr 2017 16:05:35 GMT

Hi Peter,

I want to thank you for your kind reply. Looking back, I'm rather

embarrassed at my post; chalk it up to frustration and pre-vacation

exhaustion. I was out this last week, so I'm just getting back in stride.

Immediately before my vacation, I did talk with a colleague who, I think,

got me over the hump on this issue, at least I hope so! The problem I

think I was having is simply too much detailed information, not enough

technical overview, and a terminology mismatch. For example, I already had

the documentation resources you provided; also, I had the examples too.

(I'm not discounting you providing them, thanks!)

The problem was this: I started with this example: (

https://community.nxp.com/docs/DOC-333754). I was able to compile and run

this on our debugger/hardware, so I was encouraged. However, when I ported

it to our system, I could not get the interrupts to fire. As far as I

could determine, everything is the same between the demo code and the

ported version. This had me very frustrated, and combined with a lack of

confidence that I understood anything about the chip, caused my post.

Turns out the issue is, as expected, both unrelated to getting a Machine

Check interrupt to fire, and specific to our system. I would explain more,

but it is a long story, and I think I am past the sticking point - though I

will know more in a few hours!

Thanks again, and best regards.

Bob