Monthly Archives: November 2016

WSN1120L / WNS1120CL Block Diagrams

 

wsn1120l_block_diagram

WSN1120L Hardware Block Diagram

 

wsn1120cl_block_diagram

WSN1120CL Hardware Block Diagram

 

Work in progress – New Micro

It’s  been a while  since we upgraded the microcontroller on WiSense nodes. The last upgrade was from the MSP430G2553 to the MSP430G2955.

The MSP430G2955 has 56 KB code memory (on chip flash) , 4 KB of  RAM and max clock speed of 16 MHz. The current  set of features  have  exhausted the code  memory so it is time to move to another member of the MSP430 family. This time we are upgrading to the MSP430F5419A. This is  a 100 pin micro with 128 KB  of  code  memory (again  on chip flash) and 16  KB of RAM. This micro can run at a  max  speed of 25 MHz. It has far  more  GPIO  pins (87 compared to 32 on the G2955). It has 16  12-bit SAR ADC  channels  compared  to 12 10-bit SAR ADC channels  on the  G2955. The  F5419A  has  4 “Universal Serial Communication Interface (USCI) blocks” compared to 2 on the G2955A. Obviously the F5419A costs more. So it is an upgrade on all fronts.

Since we chose to have separate PCBs  for the  micro and the  radio, changing either the radio or the micro is not a big effort.

Reduced  function devices can still use the MSP430G2955 but all FFDs and coordinator nodes will use the  MSP430F5419A going forward.

Board changes will include a 25 MHz crystal for the F5419A  and a  bigger external  EEPROM  to accommodate two 128 KB  images (for  firmware upgrade). Will add a JTAG  interface in addition to the 2 pin SPY-BI-WIRE. Debugging with the full JTAG  interface is far more convenient (and fast) compared to the SPY-BI-WIRE interface. I  have not yet decided on the PCB size and the number of GPIO pins which will be exposed.

The advantage of sticking with the MSP430 family is that all the code base (pretty big now) runs on the F5491A as it is. Peripheral register naming is slightly different between the F5419A  and the G2955. The F5419A has a highly configurable 12 bit ADC so all the device drivers using the simpler  10 bit ADC on the G2955 need to be modified to use  the new  12 bit ADC module.

I  was able to interface the CC1120 radio and  got the UART working on the F5419A. I tested both the FFD and Coordinator configurations. Looks good so far. Was not able to get the clock speed to 25 MHz maybe because I am currently using the MSP-TS430PZ5x100 Target Socket Module instead  of a PCB mounted micro.

Here are some pics of the eval setup.

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For more information, please visit wisense.in.