Bit setting help

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Bit setting help

Post by spartan09 » Tue Nov 25, 2014 10:05 am

Hello, I have a AVR question that I have been set from my class. Please note: I AM NOT ASKING YOU TO ANSWER THE QUESTION!I m just asking to see if it correct as i have no simulation software or hardware available at the time. I have supplied my answer with workings the chip i m using is a ATMega164P

An AVR is running from an 11.0592MHz clock. For serial transmission only, at 4800 Baud:

Which bit(s) in the UCSR0B need to be set?

What value needs to be loaded into the UBRR0 register? (Assume U2X0 = 0.)


My Answer:

From the data sheet I would set bits: 1<<TXCIEn | 1<< TXEn | 1<<TXB8n

The values that need to be loaded into the UBRR0 register are:

UBRR0 = ( f / (16XBaud Rate)) -1
UBRR0 = 143

So values 143 needs to be loaded into the register

Can someone who is familiar with micro controllers confirm my answers as I am new to this. If they are wrong could you please correct me. Much appreciated


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Ross Robotics
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Re: Bit setting help

Post by Ross Robotics » Tue Nov 25, 2014 5:32 pm

Double posting will NOT get you an answer faster, if anything, it will slow it down.
Available for circuit and PCB design, just PM me!

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