TWRKL25Z Tower Module Errata Page 3 of 4
the board.
Care should be taken to avoid connecting the OpenSDA mini USB at the same time, because this may cause
a short circuit!
1.2
Reset button
When the OpenSDA is not powered the reset button does not work. This is because the reset button has
been placed in the OpenSDA side of the level shifter for the reset signal.
To be able to use the reset button, it is needed to power the OpenSDA circuit. This issue does not inhibit
the POR or the external debugger reset.
1.3
Pull-ups missing from the TWRPI connector IIC
1.3.1
Issue description
The IIC signals connected to the TWRPI connector (J4, pins 1 and 2) are missing their pull-ups. These signals
are also connected to the elevator IIC signals (I2C0_SCL and I2C0_SDA) so they are also missing pull-ups if
IIC communication is needed for peripheral boards.
1.3.2
Workaround
Pull-ups can be connected to these signals externally by using the tower elevator lateral connectors. Using
through-hole resistors, connect a 2.2 k to 10 k ohm resistor. Connect between pins 7 and 3 and pins 8 and 3
of the primary elevator top lateral connector as showed in the figure below.
