----- Ursprüngliche Nachricht ----- Von: Peter Bigot Gesendet am: 09 Dez 2011 16:45:44
>>> _executed_ is a different thing. The instruction is fetched (and a >>> breakpoint >>> on it is triggered) on every MSP. >>> However, the instruction will be _executed_ the moment an interrupt is >>> triggered and LMP ends. However, it will be executed before the ISR >>> is entered, and not, as one would expect, after the ISR has ended LPM. >> I could believe this, but please provide a reference supporting your claim. > The claim is not supported by a test program using an MSP430G2553. > With this sequence: > 2c: 32 d0 f8 00 bis #248, r2 ;#0x00f8 > 30: 16 43 mov #1, r6 ;r3 As==01 > where r6 was previously zero, r6 still has the value zero within the > interrupt handler that wakes the MCU. This is entering LPM4; LPM0 > behaves the same. > Have I misunderstood what you're saying? Is there a different > situation that you meant? No, you got it right. The G series seems to be immune. (See my other post). So TI did some change in the silicon. I don't know when and where. I only know that the code above would have exposed the problem on the 1232 I worked on ~6 years ago. (interestingly, this never appeared in the 1232 errata sheet) Since then, all my operations on SR include a following NOP unless the next operation is known to be not critical. So I never checked again. And I don't have one of the old 1232 anymore. However, on many MSPs (if not all), a breakpoint on the MOV would be triggered before LPM is entered. Maybe the LMP mechanism does discard the already fetched instruction then. JMGross ------------------------------------------------------------------------------ Learn Windows Azure Live! Tuesday, Dec 13, 2011 Microsoft is holding a special Learn Windows Azure training event for developers. It will provide a great way to learn Windows Azure and what it provides. You can attend the event by watching it streamed LIVE online. Learn more at http://p.sf.net/sfu/ms-windowsazure _______________________________________________ Mspgcc-users mailing list Mspgcc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mspgcc-users
