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Power - JTAG question .

Started by praveen July 19, 2004
Please omit the previous email. Hi All I have a question. I am using my own design board. I am using the JTAG
to program the board. What about the power supply. The pin 11 of the
JTAG connector requires 3.3 v. Is this supplied by the parallel port?.

I connect the board through the newmicro JTAG and then to the
parallel port.

Should I connect an external source (3.3 v) to the pin11? In general
how the JTAG connector is powered. Is it through the parallel port or
it requires an external source. Can any one help me on this? Thanks
Praveen



Praveen,

Pin 11 of the command converter should be connected to the I/O supply
on your board. It powers the output buffer for the logic translation so
the output is at the correct voltage for the device you are using.
Typically this is 3.3v...

--
dB

--- praveen <> wrote:
> Please omit the previous email. > Hi All > I have a question. I am using my own design board. I am using the
> JTAG
> to program the board. What about the power supply. The pin 11 of the
> JTAG connector requires 3.3 v. Is this supplied by the parallel
> port?.
>
> I connect the board through the newmicro JTAG and then to the
> parallel port.
>
> Should I connect an external source (3.3 v) to the pin11? In general
> how the JTAG connector is powered. Is it through the parallel port or
> it requires an external source. Can any one help me on this? > Thanks
> Praveen >

__________________________________


Hello Praveen

It seems to me that the JTAG converter receives 5 V from the parallel
port for one half of its level translation, and 3.3 V from the target
board for the lv end of its level translation.

Best regards
Robert On Jul 19, 2004, at 1:12 AM, praveen wrote:

> Please omit the previous email. > Hi All > I have a question. I am using my own design board. I am using the JTAG
> to program the board. What about the power supply. The pin 11 of the
> JTAG connector requires 3.3 v. Is this supplied by the parallel port?.
>
> I connect the board through the newmicro JTAG and then to the
> parallel port.
>
> Should I connect an external source (3.3 v) to the pin11? In general
> how the JTAG connector is powered. Is it through the parallel port or
> it requires an external source. Can any one help me on this? > Thanks
> Praveen
>