Using LaunchPadXL JTAG to debug a SensorWeb board - mozilla-sensorweb/sensorweb-wiki GitHub Wiki

When I got my SensorWeb board, the JTAG portion of the board wasn't working properly.

This page describes how to connect up the JTAG from a CC3200 LaunchPadXL board to use with the SensorWeb board.

  • On the LaunchPad board, remove jumpers J6 & J7 (FTDI Tx/Rx), J8, J9, J10, and J11 (TCK, TMS, TDI, and TDO).
  • On the SensorWeb board, remove jumpers J15 & J16 (FTDI Tx/Rx), and all 4 jumpers on J18, and J11 (power selection).
  • Connect Ground from the Launchpad to ground on the SensorWeb. I used J20 on the LaunchPad and pin 4 of J1 on the SensorWeb (pin 4 is furthest from the edge of the board).
  • Connect VCC from the LaunchPad (also on J20) to the center pin of J11 on the SensorWeb board.

Photo of VCC/GND locations on the LaunchPad board VCC & GND connections on the LaunchPad

Photo of VCC/GND locations on the SensorWeb board VCC & GND connections on the SensorWeb board

  • Connect The JTAG signals. On the LaunchPad board you want to use the pins on the JTAG side of the 2x4 header (the side with the labels TCK/TMS/TDI/TDO). On the SensorWeb side use the 4 pins closets to the processor. Note that the order of the pins on the SensorWeb board is different from the LaunchPad board. On the SensorWeb board, the order is TCK/TDI/TMS/TDO, with TCK being the pin closest to the power jack. In the photos, the wire colors are brown/TCK, orange/TDI, red/TMS, and yellow/TDO. I used 4" long jumper wires. I found that I got too many errors when using 8" jumper wires.

Photo of the JTAG and UART connections on the LanchPad board JTAG & UART connections on LaunchPad

Photo of the JTAG and UART connections on the SensorWeb board JTAG connections on the SensorWeb board

  • Connect the UART signals. On the Launchpad, these are J6 and J7. Use the pin on the JTAG side of the board (closest to the J6/J7 labels). Connect J6 (grey) to J15 (pin furthest from power jack). Connect J7 (white) to J16 (also pin furthest from power jack). Note that you'll need to leave the MCU on the LaunchPad board powered if you want the UART signals passed through, since there is a buffer chip on the LaunchPad UART lines which is powered from the same VCC which powers the MCU.

Photo showing SensorWeb UART connections UART signals on SensorWeb board

You should now be able to plug in the LaunchPad USB and use the JTAG/UART.