About timer operation in 8051 micro controller

Replies

• 

  Harshad Italiya

  #-Link-Snipped-# can you share your keil project .zip file here?
• 

  sparsh sharma

  Harshad Italiya

  #-Link-Snipped-# can you share your keil project .zip file here?

  #-Link-Snipped-#
  i have written just a small program to check the working of timer in mode 2.
• 

  IanSiladi

  The problem is looking in your code. Are you enable to put the count that should be copied into the TL from the TH?
  Also what about your interrupt handling?
  Are you using any kind of the hardware interrupt here, specially for your timer-counter?
  
  #-Link-Snipped-#
• 

  sparsh sharma

  IanSiladi

  The problem is looking in your code. Are you enable to put the count that should be copied into the TL from the TH?
  Also what about your interrupt handling?
  Are you using any kind of the hardware interrupt here, specially for your timer-counter?

  This code is written just for the purpose of understanding the Timer operation in MODE 2 of 8051uc. i have also simulate it on keil uvision3 software. the snap shot of the output i have attached.
  and count in TL0 is loaded with TH0 contents only if TF0 is made high internally, initially TL0 starts with 00h.
  and about interrupt i am using the polling/status check method not using any hardware interrupt.
  just checking the TF0 bit status
• 

  Harshad Italiya

  #-Link-Snipped-# :
  8051 Timer 0 Mode 1 Example Program
  8051 Timer 1 Mode 2 Example Program
  You can find Timer 0 example code from KEIL. Try this and see if this is working for you properly or not.
• 

  sparsh sharma

  Harshad Italiya

  #-Link-Snipped-# :
  8051 Timer 0 Mode 1 Example Program
  8051 Timer 1 Mode 2 Example Program
  You can find Timer 0 example code from KEIL. Try this and see if this is working for you properly or not.

  yes its working but with the same way as i have mentioned, there is a need to load the TLx register first, there is no auto reload initially in this mode2. auto reload happens only after the generation of Timer Flag internally.
  Thanks
• 

  Harshad Italiya

  sparsh sharma

  yes its working but with the same way as i have mentioned, there is a need to load the TLx register first, there is no auto reload initially in this mode2. auto reload happens only after the generation of Timer Flag internally.
  Thanks

  I am still not getting you. Have you checked what is the difference between your code and the example code?
• 

  sparsh sharma

  Harshad Italiya

  I am still not getting you. Have you checked what is the difference between your code and the example code?

  yes i checked, there is no difference, both are same
  thank you sir