There are a few common reasons that a user is
unable to connect to a LaunchPad. To determine which of these steps are relevant,
follow the instructions in How to test your JTAG connection with
CCS to Test Connection to the LaunchPad. Before using the
following steps, disconnect any BoosterPack™
Plug-in Modules or other external hardware from the LaunchPad.
If the log from the Test Connection
indicates that the Test Connection cannot communicate with the debug
probe, try the following steps:
Change the USB cable and
make sure that the correct debug probe is selected in the Target
Configuration file.
Check the hardware
switches and jumpers on the LaunchPad to see if any can disable the JTAG
connection. This information is in the LaunchPad User's Guide, which is
usually linked on the TI.com store page for the LaunchPad.
If the Test
Connection log still shows that the Test Connection
cannot communicate with the debug probe, there is a possibility that the
LaunchPad has been damaged. This is especially likely if the debug probe
is not visible in the device manager of the PC.
If the log from Test Connection mentions
that the Test Connection cannot circulate bits or that the IR or DR paths
are broken, try the following steps:
Check the hardware
switches on the LaunchPad to see if any disable the JTAG connection.
This information is in the LaunchPad User's Guide, which is usually
linked on the TI.com store page for the LaunchPad.
Some LaunchPads are
designed to work only with 2-pin cJTAG or only with 4-pin JTAG. This is
set in the Advanced tab of the target configuration. Make sure to
set this correctly.
If the Test
Connection log still indicates that the Test Connection
cannot circulate bits, there is a possibility that the LaunchPad was
damaged.
If the log from Test Connection denotes
that the test passed, but code still cannot be loaded to the device, try the
following steps:
Use the switches on the
LaunchPad to put the device in wait boot mode. If you are then able to
connect by following the manual launch steps,
then there was likely something in the previously flashed code that was
preventing the connection.
If a connection is still
not possible, or the connection worked but code cannot be loaded, it is
possible that the device is locked.