EVB9S12NE64 CW v6.1 write to port problem

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EVB9S12NE64 CW v6.1 write to port problem

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mtumarc
Contributor I
Im using an EVB9S12NE64 with codewarrior v6.1, build 6037. I am attempting to drive LEDs using port B but cannot seem to change the portB value. I am programming in assembly and would think simply loading an accumulator and storing the accumulator value to PortB would suffice although no state change is observered. Does anyone have a sample code or other suggestions?
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mtumarc
Contributor I
 are the port addresses for the EVB different than those of the actual MCU?
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JimDon
Senior Contributor III
No. They are the same.
I don't think it is an issue with communicating with the board, unless you are saying that CW is showing some thing other that what you wrote to the port.

I/O ports can be moved - this is rarely done, but you could check that. There is a register you write to to change that base address of the ports. I have not ever done this, but it is possible.

The only other thing I can think of is a pull up. The chip has active pull ups, so you should see a signal.
What is this pin driving?

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Xbot
Contributor II
Give him a sample code already... he just want to check if his board is ok. geez
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mtumarc
Contributor I
is seems as if there is an issue communicating with my board. codewarrior is showing that the memory byte indicated as portb on the data sheet is being changed although there is no change on the actual port. any suggestions?
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mtumarc
Contributor I
I have set DDRB to configure the port as an output, and do notice a .5V drop when the uC executes that instruction but i cant change between '1' and '0'. Im using $0001 as the portb address. Is that the correct address?
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JimDon
Senior Contributor III
Well, if you don't  already have this, down load it and look on page 25.That should answer all you questions in this regard.

What is the load on this pin? If it is open, it should be able to got to at least 4v. Could it be shorted?


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JimDon
Senior Contributor III
Did you set the direction register to output for that bit on that port?
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