[hpsdr] Atlas bus lines C29 and C31

[Bill Tracey]

A27, A29, A31, C27. C29, and C31 are not paralleled as the other 
Atlas lines are - they're cross connected so you can get a chain from 
slot to slot to slot.   A27 and A29 are used for the JTAG chain and 
at the time Atlas was done it was thought to be a good idea to have a 
few more setup that way.     You're not the first to get caught by this one!

Cheers,

Bill (kd5tfd)


At 05:56 PM 3/20/2011, Joe Martin K5SO wrote:
>***** High Performance Software Defined Radio Discussion List *****
>
>
>All,
>
>Relax.  As Joe K1RQG points out to me, from the Atlas documentation 
>it seems that C29 and C31 have been made intentionally different 
>from most bus lines, for some reason.
>
>However, this mean that the communications specification that we 
>currently have for comm lines between Ozy/Magister/Metis and Mercury 
>is invalid, as C29 and C31 fall in the middle of the 8-line comm 
>spec that exists for that specification.
>
>In Metis v1.1 and Ozy 6.3 I avoided use of the C29 and C31 lines and 
>used A6 and A4 instead for those two sets of firmware.
>
>It occurs to me that the two "missing" data lines (C29 and C31) of 
>the 8-line comm spec could easily be the reason were earlier were 
>plagued with strange audio "popping" phenomena.  Lately many of the 
>apps run using only a single NWire communication between the boards 
>so the "missing" lines weren't important, until you try to use one 
>of them for the NWire comm, hihi.
>
>Sorry to put out a general alert but it sure looked like one was 
>warranted to me at the time.
>
>73,  Joe K5SO


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