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Difference between Brown out and Power on reset

electronicsLearner77

Jul 2, 2015
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I am bit confused with these terms as Brown out reset is set when the voltage is less than Vdd. So when you are powering ON it should go from lower voltage to Vdd. In this case how micro chip handles?
 

BobK

Jan 5, 2010
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It would help if you told us what device you are talking about.

Bob
 

Amar Dhore

Dec 2, 2015
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Brown out reset flag gets set when the VDD drop below the operating voltage. It holds the reset high for some time. Check the datasheet for more information.
 

electronicsLearner77

Jul 2, 2015
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Sorry but please explain me this scenario.
1. I powered on the board for the first time. Will the brown reset flag will be set or not?
 

hevans1944

Hop - AC8NS
Jun 21, 2012
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You should find that both POR and BOR bits <1:0> are set in RCON after initial power on. All other bits in RCON should have been cleared as a result of the power-on reset. As part of your program initialization after initial power on you should clear both POR and BOR bits so that the contents of RCON represent future events accurately.

Have you read, and do you understand, the datasheet for this microprocessor? It appears to be quite sophisticated. It has been my experience with PIC micros that it is absolutely necessary to understand how each and every bit in all the registers functions before you can write correct code. The RCON register is just a status register to provide information to your program. Setting or clearing any of the bits in RCON will not create an actionable event for the microprocessor. This will not be true for other bits in other registers, whose state will determine what the microprocessor does. Read carefully and understand the purpose and function of each bit in every register. Consider using a higher level language, such as C, to shelter you from most of this.
 
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