1 Reply Latest reply on Mar 7, 2018 2:00 AM by prbd

    Please clarify statements in the datasheet of STK15C88

    michael.berberich

      In the Datasheet (Revision D, 16th Feb 2012) of STK15C88 in the chapter "Hardware Protect"
      the following text passage ist shown:
       When VCAP < VSWITCH, all externally initiated STORE operations and SRAM WRITEs are inhibited.

      Now i have the following questions:
       
      1.)  I think that VCAP is the operating voltage at the device. I found no explanation about this
             voltage in the whole datasheet. Am i right?
      2.)  I understand this protection mechanism as follows:
            If an autostore operation is running, no writes from a processor are possible to the SRAM-
            aerea of the device STK15C88. Is this right and what is the reaction of the device in this case?
      3.)  What happens if a write operation is done in the moment when Vcc (mentioned VCAP??)
             passes Vswitch and so initiates an autostore operation while the write is still running?
         
      Thanks for your answers!

      Mike

        • 1. Re: Please clarify statements in the datasheet of STK15C88
          prbd

          Hi Mike,

           

          Please find our comments below.

           

          1.)  I think that VCAP is the operating voltage at the device. I found no explanation about this

                 voltage in the whole datasheet. Am i right?

          Ans) Yes, you are correct.

           

          2.)  I understand this protection mechanism as follows:

                If an autostore operation is running, no writes from a processor are possible to the SRAM-

                aerea of the device STK15C88. Is this right and what is the reaction of the device in this case?

          Ans) Yes it is correct. During autostore the commands will be ignored.

           

          3.)  What happens if a write operation is done in the moment when Vcc (mentioned VCAP??)

                 passes Vswitch and so initiates an autostore operation while the write is still running?

          Ans) That write operation if completed will be reflected in the memory. If it is not completed then that operation will fail.

           

          Thanks,

          Pradipta.