7 Replies Latest reply on Apr 3, 2015 10:57 AM by ArvindS_76

    Wiced Sense power optimisations

      Hi,

       

      I am developing an Android app that uses data from WICED Sense. I expect my end-users to buy WICED Sense tags, download my app and then connect Sense to my app.

       

      Everything is working fine. But before announcing the app publicly, I have a few questions:

       

      • The battery life for the Sense with firmware version 1.3 is not very high. The battery goes weak after about 2 hours of use. Does Broadcom have any plans to address this?
      • Where is the source code for firmware version 1.3? I would like to try my hand at tweaking it. I only see a post about firmware v1.2.
      • Can any firmware (custom) be installed on the Sense tag and is this a recommended practice? Does the firmware need to be signed?                                                                                 
      • How much power is consumed when blinking LEDs and playing beeps? Can we increase battery life by reducing the blinks and the beeps?
      • How much power is consumed when connected but not sending data?
      • How much power is consumed when connected and sending data (from SENSE to GATT client)?  Can we increase battery life significantly by reducing the number of transmissions?

       

       

      thanks,

      HRJ

        • 1. Re: Wiced Sense power optimisations

          Hello HR

           

          The battery life for the Sense with firmware version 1.3 is not very high. The battery goes weak after about 2 hours of use. Does Broadcom have any plans to address this?

          [JT] - Correct.  Broadcom does plan to address this.

          • Where is the source code for firmware version 1.3? I would like to try my hand at tweaking it. I only see a post about firmware v1.2.

          [JT] - Please use firmware v 1.2 - v 1.3 has not been released - Check links for possible updates.

          • Can any firmware (custom) be installed on the Sense tag and is this a recommended practice? Does the firmware need to be signed?

          [JT] - Please see links:

          WICED Sense Firmware Source Kit

          [JT] - Power analysis has not been done in this scenario.  Yes, however most battery power is consumed by the sensors and the RF Technology

          • How much power is consumed when connected but not sending data?

          [JT] - Depends on several factors - detailed measurements of this scenario have not been measured

          • How much power is consumed when connected and sending data (from SENSE to GATT client)?  Can we increase battery life significantly by reducing the number of transmissions?

          [JT] - Power analysis has not been done on the WICED Sense Platform - This platform was designed to send sensor information as quickly as possible.  Yes, reducing the number is transmissions will significantly increase battery power.

           

          Thanks

          JT

          1 of 1 people found this helpful
          • 2. Re: Wiced Sense power optimisations

            Thanks JT for your detailed response.

             

            I have made my app's WICED integration public:

            https://www.reddit.com/r/skeye/wiki/remote-sensors

             

            Many of my app's users have shown interest and couple of them have already ordered the WICED sense within one day! They are happy but complaining that the device eats through batteries.

             

            What are the changes between firmware version 1.2 and 1.3, and is there an ETA for the source-code release of 1.3? If I have to create custom firmware, I would prefer basing it on the latest firmware from Broadcom, to avoid reinventing the wheel.

            • 3. Re: Wiced Sense power optimisations
              BoonT_56

              i believe the current fw version is still 1.2 as below:

               

              WICED Sense SDK 2.1 Firmware.zip

              • 4. Re: Wiced Sense power optimisations

                But the Play store app for WICED Sense allows me to update to version 1.3.

                 

                This is what it says on the Play store:

                 

                Fixed ANR/Crash issue after OTA update to 1.3.

                NOTE: WICED Sense Tag MUST be upgraded to firmware version 1.3.

                • 5. Re: Wiced Sense power optimisations

                  Hello HR,

                   

                  Have you tried to upgrade your WICED Sense Kit from the SDK 2.2 Download?

                   

                   

                   

                  WICED Sense Recovery Procedure Video

                   

                  The version of the firmware is in the header file and is version 1.3:

                   

                  #define WICED_SENSE_APP_ID 0x3A20

                   

                  #define WICED_SENSE_APP_VERSION_MAJOR 1

                   

                  #define WICED_SENSE_APP_VERSION_MINOR 3

                  Hope this helps,

                  JT

                  • 6. Re: Wiced Sense power optimisations

                    Oh, cool. I hadn't tried that, good to know that firmware v1.3 code is already available.

                     

                    Btw, there's some good news. My estimate of 2 hours of battery life was way off. I tried with a fresh battery and got 9 hours out of it. The two hour battery life was probably due to frequent connects / disconnects during development.

                     

                    Details of the test here.

                    • 7. Re: Wiced Sense power optimisations
                      ArvindS_76

                      > Can any firmware (custom) be installed on the Sense tag and is this a recommended practice? Does the firmware need to be signed?

                      Sure! You can use the SDK to develop your own apps for the Sense. Drivers for the ST sensors are included in the wiced_sense sample app.

                       

                      > How much power is consumed when blinking LEDs and playing beeps? Can we increase battery life by reducing the blinks and the beeps?

                      The LEDs and the buzzer consume some power, especially if you connect/disconnect often. You can disable them (the app in the Sense will need to be changed).

                       

                      > How much power is consumed when connected but not sending data?

                      Much of the current drain is due to the sensors. If you need to be idle and with a say, 1s connection interval, the average current draw is of the order of  a couple of 100s of uA or less for the connection. The rest of it is the sensors. If your application knows exactly when the sensors are needed and when they are not, the app can put the sensors in deep sleep (hundreds of uA draw instead of many mA when awake) when not needed (while still remaining connected). The sample wiced_sense app turns on all sensors as soon as it connects to the client and puts them into low power mode when it disconnects.

                      2 of 2 people found this helpful