2/24/2010 1:21 PM | |
Joined: 10/7/2005 Last visit: 7/15/2024 Posts: 3009 Rating: (1053)
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Hello Mikkel Fog I think theconfusion comes from the fact that the Max_Tsdr isstipulated in theGSD file of EACH DP Slave but it also appearsas a single value in the Busparameters of the DP Master. While both values mean the same they are not automatically linkedto each other. The Max_Tsdrin the DP Slave is the maximum allowed time (in t bits) that your DP Slave can take before it starts sending back the response message to the Master. There is also a set of standardMax_Tsdrfor each baudrate which are listed below: MaxTsdr_9.6 = 60 MaxTsdr_19.2 = 60 MaxTsdr_45.45 = 400 (Note: also used as PA baudrate, thus larger value) MaxTsdr_187.5 = 60 MaxTsdr_500 = 100 MaxTsdr_1.5M = 150 MaxTsdr_3M = 250 MaxTsdr_6M = 450 MaxTsdr_12M = 800 |
Cheers |
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2/28/2010 1:38 PM | |
Joined: 10/7/2005 Last visit: 7/15/2024 Posts: 3009 Rating: (1053)
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Hello Mikkel Fog
That is correct to the best of my knowledge. Step7 will simply use the previously listed "Standard" values for Max_Tsdr and other bus parameters ifthe bus profile is set to DP Standard.
I suppose so, but ideally you make sure that your DP Slave is developed to NOT exceed the "Standard" values for Max_Tsdr. I have not yet come across a DP Slave that has a higher Max_Tsdr in its GSD file than the "standard" ones, but there's plenty of Slaves with lower Max_Tsdr than the "standard" one out there (which is of course a good thing).
Not too sure what's wrong here, but bear in mind that the Slot Time is the one and only important one for the DP Master to check for Slave timeouts. It starts counting down when the last bit of the request message has been sent and the firstByte (11 bits) of the response message MUST be fully received within this time (otherwise the Master will do aretry). 100 is the "standard" Slot time for 19.2Kbps which means you (should) actually have some5.2ms time. You however are only measuring half of that and already have a timeout, so I am a bit at a loss to explain thisbut hope this helps anyway. |
Cheers |
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