Hot!what is better?internal or external oscillator?enable or disable MCLR pin ?

Author
EMB
Starting Member
  • Total Posts : 19
  • Reward points : 0
  • Joined: 2016/05/16 07:49:26
  • Location: 0
  • Status: offline
2018/09/14 05:32:00 (permalink)
0

what is better?internal or external oscillator?enable or disable MCLR pin ?

Hi All,

I'm designing a digital alarm system using DS3231 RTC and PIC18f4520.
as pic18f4520 has internal oscillator and ability to enable/disable MCLR Pin.

what is better internal or external osc?enabling/disabling MCLR PIN?

Regards ;)  
#1

3 Replies Related Threads

    MBedder
    Circuit breaker
    • Total Posts : 6519
    • Reward points : 0
    • Joined: 2008/05/30 11:24:01
    • Location: Zelenograd, Russia
    • Status: offline
    Re: what is better?internal or external oscillator?enable or disable MCLR pin ? 2018/09/14 05:33:59 (permalink)
    +2 (2)
    Ice cream is better by all means.
    #2
    NorthGuy
    Super Member
    • Total Posts : 5076
    • Reward points : 0
    • Joined: 2014/02/23 14:23:23
    • Location: Northern Canada
    • Status: offline
    Re: what is better?internal or external oscillator?enable or disable MCLR pin ? 2018/09/14 06:04:38 (permalink)
    +2 (2)
    Any time the manufacturing offers an option,  this is because in some situations one choice is more suitable, but in other situation you may need a different choice.
     
    Fore alarm system, you probably don't need an external crystal and internal oscillator will do just fine, but if you need to maintain time, the internal oscillator will not be enough, thus you need something, such as RTCC.
     
    It's a good idea to enable MCLR and not mess with it unless you're running out of pins.
     
    Speaking of choices - selecting an obsolete microcontroller for new designs is rarely a good choice. There are many new PIC18s, and also newer PIC16F1*. These will be much better choice.
    #3
    katela
    Super Member
    • Total Posts : 982
    • Reward points : 0
    • Joined: 2013/06/11 05:25:18
    • Location: South Africa
    • Status: offline
    Re: what is better?internal or external oscillator?enable or disable MCLR pin ? 2018/09/14 06:17:01 (permalink)
    +3 (3)
    This topic has been discussed many times here, a simple search will point you to the right place. Like these topics:
    https://www.microchip.com/forums/m410758.aspx
    https://www.microchip.com/forums/m955159.aspx
    You are the one to decide which one is better for your application depending on extra cost and accuracy. For communication protocols it's always better to use an external crystal.
      

    Free online Microcontroller Tutorials and Projects for Hobbyists and students. From beginners to advanced. Website: www.studentcompanion.co.za
    YouTube Tutorials: https://www.youtube.com/user/StudentCompanionSA
    #4
    Jump to:
    © 2018 APG vNext Commercial Version 4.5