ULINK: USING ULINK2 ON LPC2000 DEVICES

Information in this article applies to:

• ULINK2 JTAG Adapters

PROBLEM

Custom boards using LPC2000 devices that download and debug with the ULINK JTAG adapter do not work properly with ULINK2 JTAG adapter.

CAUSE

This problem is typically caused by a component (such as a voltage supervisor) that is connected to the JTAG RESET pin. If the component draws too much current, it could prevent ULINK2 from controlling the /RESET signal.

The older ULINK adapter is more tolerant of components that draw higher-than-normal current connected to the /RESET pin. ULINK2 expects standard digital current draw on that pin.

RESOLUTION

One solution is to install a 1K ohm resistor between the component and the RESET pin. This reduces the amount of current required to control the /RESET signal and allows ULINK2 to work.

SEE ALSO

• ULINK: START PROBLEM WITH PHYTEC PHYCORE LPC2294

FORUM THREADS

The following Discussion Forum threads may provide information related to this topic.

• Re-programming through JTAG fails the 1st try, works the 2nd try

Last Reviewed: Thursday, September 20, 2007