GTA04 ... JTAG

Mike (mwester) mwester at
Tue Apr 29 23:45:46 CEST 2008

Andy Green wrote:
> Somebody in the thread at some point said:
> | Joerg Reisenweber wrote:
> |> Please, before we start to mux UARTs again, and get real bad headache
> |> like on GTA01
> |
> | Yeah, I also don't particularly like this. We've been bitten before
> | by this sort of multiplexing. Granted, it's more contained in this
> | case than on GTA01.
> Yeah, muxing something like that needs an excuse rather than getting
> waved through.  However the two modes are very distinct, you are either
> blowing flash in MSP430 or you are seeing Linux console traffic, and the
> modality is controlled by and affects only the FTDI interface.

A plea from someone in the field: Please, please, please no more muxes.

No matter how many use-cases are considered, nor how simple the 
situation may seem to be, nor how comprehensive the mux design might be, 
Murphy _will_ strike, and he prefers to wait until long after you've all 
moved on the GTA05 or GTA06 or whatever...  Then we'll discover (like 
the GTA01) that as one unforseen horror is resolved, another one as bad 
or even worse lies just beyond.

No comment on the JTAG, just begging for no more muxes.

Mike (mwester)

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