Bernard Mentink wrote:
> Hi Janne,
> 
> I presume by MSP-FET you mean the target board micro? (Confused, as my
> understanding of an MSP-FET is a parallel port to JTAG adapter sold by
> TI ???)
> If you mean the former, then the pins you specify don't match up with
> the page in the manual.
> 
> The manual shows pin 8 of the JTAG header going to the TEST pin on the
> device (which is pin 1 on the 2232) and pin 1 on the JTAG header no
> longer goes to pin 38 on the 2232 (for JTAG mode) but
> now goes to pin 7 (reset). I presume if the the JTAG pins are connected
> they are not used in this mode and can be ignored.
> 
> So my question is: Do I follow the manual circuit (Fig-3-1) or do I try
> to connect as your instructions as they are different. Can you not
> supply a schematic? A picture is worth a 1000 words!
> 
> Thanks,
> Bernie
> 

Hi Bernie,

SBW doesn't work at all with parallel port JTAG. You must use USB FET for
that. Here is a drawing of direct connection of SBW. My explanation was based
on the assumption that you have 4-wire JTAG header on your 2232 target, like
me. TEST/VPP connection is not necessary unless you want to blow the JTAG
fuse which I assume is something you don't want to do right now. You are
right, "normal" JTAG pins are not used with SBW.

Here is the adapter schematic to convert from 4-pin JTAG to SBW:

http://koti.mbnet.fi/jahonen/Electronics/Stuff/SBWAdapter.png

As you can see, only two pins are used other than VCC and GND.

To directly connect the 2232 to the USB FET (without JTAG fuse blow option):

http://koti.mbnet.fi/jahonen/Electronics/Stuff/SBWConnection.png

These two lead to same result, but using a SBW connected pinheader avoids the
mess with adapters.

Regards,
Janne

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