strange bug with I2C and reset (LPC2103)

Started by dauzat_lilian August 4, 2007
hello,

I would like to report a very strange bug I found:
I'm working on a LPC2103 based system. The LPC communicates with a
classD audio amplifier from NS: LM4947.

We found the following bug:
It's impossible to programm the LPC more than on time using the JTAG
We realized that it is impossible to reprogram the LPC if the LM4947
is ON.

Very strange...........

Best,
Lilian

An Engineer's Guide to the LPC2100 Series

Hello,

> I would like to report a very strange bug I found:
> I'm working on a LPC2103 based system. The LPC communicates with a
> classD audio amplifier from NS: LM4947.
> We found the following bug:
> It's impossible to programm the LPC more than on time using the JTAG
> We realized that it is impossible to reprogram the LPC if the LM4947
> is ON.
> Very strange...........

And why ? Because of using the I2C ? Or because the LM4947 disturbs you JTAG
port ? Or ...
I think these are too less details to say something about the error or try
to reproduce it.

Regards,

Martin
----- Original Message -----
From: "dauzat_lilian"
To:
Sent: Saturday, August 04, 2007 3:17 PM
Subject: [lpc2000] strange bug with I2C and reset (LPC2103)
> hello,
>
> I would like to report a very strange bug I found:
> I'm working on a LPC2103 based system. The LPC communicates with a
> classD audio amplifier from NS: LM4947.
>
> We found the following bug:
> It's impossible to programm the LPC more than on time using the JTAG
> We realized that it is impossible to reprogram the LPC if the LM4947
> is ON.

The amplifier pulses affecting the JTAG signals?

Leon