4 Replies Latest reply on Jan 9, 2013 3:28 PM by daniel.hernandez

    Real Time Clock (RTC)

    daniel.hernandez

      Let me start by giving you some background on my device, my device is battery operated, when the battery is in its turned on when its not its off, I use a RTC to keep track of the amount of time that passes between uses of my device, it has an independent battery to keep the RTC powered. I'm currently using a M41T94MQ6E (RTC with 44B of Ram that communicates through SPI) and a 25AA320A (32K memory storage) for my RTC information storage.

         

      Is it possible to replace all that functionality on the CY8C5568AXI-060? I basically need to know when my device is turned on and how much time passes between the periods where its turned off. I have a small coil cell battery on my board that powers the RTC when the primary battery is not in the device.

        • 1. Re: Real Time Clock (RTC)
          user_14586677

          The answer is yes for the RTC portion.

             

           

             

          http://www.mymcu.ru/content/articles/Cypress/AN66083.pdf

             

           

             

          For 32KB of RAM, do you need hi speed RAM of just storage for

             

          time stamps, etc.. ? If latter you can use program memory as a

             

          store.From the datasheet -

             

           

             

          5.2 Flash Program Memory

             


          Flash memory in PSoC devices provides nonvolatile st
          user firmware, user configuration data and bulk data s
          The main flash memory area contains up to 256 KB of
          program space.

             


          Up to an additional 32 KB of flash space is available fo
          device configuration data and bulk user data. User code
          be run out of this flash memory section. The flash outp
          bytes wide with 8 bytes of data and 1 additional byte.

             

           

             

           

             

          Regards, Dana.

          • 2. Re: Real Time Clock (RTC)
            user_14586677

            Note there is up to 64 KB SRAM in a PSOC 5, which will retain all the

               

            way down to hibernate mode. 1.71V for hibernate, LP versions.

               

             

               

            Regards, Dana.

            • 3. Re: Real Time Clock (RTC)
              user_14586677

              Sorry, earlier past truncated on FLASH -

                 

               

                 

              5.2 Flash Program Memory

                 


              Flash memory in PSoC devices provides nonvolatile storage for
              user firmware, user configuration data and bulk data storage.
              The main flash memory area contains up to 256 KB of user
              program space.

                 


              Up to an additional 32 KB of flash space is available for storing
              device configuration data and bulk user data. User code may not
              be run out of this flash memory section. The flash output is 9
              bytes wide with 8 bytes of data and 1 additional byte.

                 

               

                 

              Regards, Dana.

              • 4. Re: Real Time Clock (RTC)
                daniel.hernandez

                Dana,     

                 

                   

                      

                 

                   

                Thanks for the quick response.     

                 

                   

                      

                 

                   

                To answer your earlier question all I am essentially storing is a time stamp and the on and off status of the device itself. So I don't really need any high speed RAM. Although I could change this to accommodate a new design.     

                 

                   

                      

                 

                   

                I have a question how would the RTC continue to operate without an external power source, or do I hook up the current battery to the Microprocessor? If so how would I do that?