This is where I'm going with fwcontrol
Sean Bruno
sbruno at miralink.com
Fri Aug 29 21:02:52 UTC 2008
Dieter wrote:
>>> Should
>>>
>>>
>>>
>>>> Message ID Root ID R T Gap Count
>>>> 00(2 bits) (5 bits) 1 1 (6 bits)
>>>>
>>>>
>>>
>>> be
>>>
>>> Message ID Root ID R T Gap Count
>>> 00(2 bits) (6 bits) 1 1 (6 bits)
>>>
>>> send_phy_config() ANDs root_node with 0x3f, and the
>>> "Physical ID" field in the controller register is
>>> 6 bits.
>>>
>>>
>> Well, according to the 1394 documentation, no. The root ID is
>> definitely 5 bits.
>>
>> The gap count is also 5 bits, I must have mis-counted. So, really it
>> should be:
>>
>> Message ID Root ID R T Gap Count
>> 00(2 bits) (5 bits) 1 1 (5 bits)
>>
>
> Looking at "Table 5. PHY Register Map" in the VIA controller datasheet
> (page 24 of the pdf)
> http://www.datasheetarchive.com/pdf-datasheets/Datasheets-6/DSA-113181.pdf
>
> the "Physical ID" field is 6 bits, as is the "Gap Count" field.
> I don't have the IEEE documentation, so I'll have to assume
> you are correct about it saying 5 bits. So why doesn't the
> controller datasheet agree with the IEEE doc? Granted one is
> a controller register and the other is a packet, but I'd
> expect these individual fields to be the same size.
>
>
>> This means that the Root ID and the Gap Count cannot exceed 0x3f(63).
>>
>
> That's 6 bits. 5 bits would be 0x1f = 31 decimal.
>
>
Huh....I seem to be having some kind of wierd PDF rendering issue.
Ok, so looking at the document in another application(not acroread),
the Node ID is 6 bits, the Gap Count is 6 bits. I'm the crazy one I guess.
Wierd.
>> So, the masking
>> of the values instead of generating and error seems wrong to me. I'm
>> going to put in error checking
>> to make sure the values comply with the specification and document the
>> correct values in the man page
>> and the comments of the code.
>>
>
> Sounds good.
>
--
Sean Bruno
MiraLink Corporation
6015 NE 80th Ave, Ste 100
Portland, OR 97218
Phone 503-621-5143
Fax 503-621-5199
MSN: sbruno at miralink.com
Google: seanwbruno at gmail.com
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