XGATE + S12X Concurrency Issues

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SleepyKeys
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Re: XGATE + S12X Concurrency Issues

Post by SleepyKeys »

Fred wrote:
Sean0 wrote:Im talking about reading/writing to a shared register without a condom on.
LOL! No, I was talking about when you had some instructions misaligned at some point and it locked up. Considering the manual states that S12 takes precedence if two accesses occur at the same time, I'll require some pretty hard evidence (not circumstantial) to believe otherwise :-)
Fair enough :-) I'll do my worst.
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Dan
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Re: XGATE + S12X Concurrency Issues

Post by Dan »

Sean0 wrote:I think
"Avoid using the same ports for XGATE BB as we do for any other type of BB IO"
and
"The simple solution is to keep XGATE BB off of port A all together and delegate nothing."
is the correct choise. It's simpler which means faster to develope, better performance and a simpler config.
I agree with Sean here. It's not like we are exactly short on io pins here, especially with the 144-pin CPU package.
nhtshot
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Re: XGATE + S12X Concurrency Issues

Post by nhtshot »

Sean0 wrote:
Fred wrote:I think that it's a false observation. If both cores desire access, S12 wins. Define "unsafe"?
I belive you're thinking of requesting access to a hardware semaphore. Im talking about reading/writing to a *shared register without a condom on.
It doesn't crash. I've abused that quite a bit and the S12 wins every time. The Xgate blocks and gets to do it's business once the S12 is done.
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