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PLEASE HELP!  Processor = MCF523X, CodeWarriors V10, external Flash memory connection question

Question asked by Dan Wermers on Apr 8, 2011
Latest reply on Apr 12, 2011 by Dan Wermers

PLEASE HELP -- PLEASE HELP -- PLEASE HELP --

 

My design uses the MCF5232 processor with an 16 bit external flash chip(s).  Got back 10 prototypes some months ago, and have been programming using the internal 64K SRAM on the processor.  Everything OK.  But now I'm past the 64K limit and need to run my code from external Flash memory.  I've managed to erase and blank check the flash boot chip, but cannot program it.  Simple quesions concerning how to connect a 32 bit ColdFire uP to a 16 bit flash device:

 

A)  I've connected A0 on the processor to A0 on the Flash chip (A1 to A1, A2 to A2, etc...).  Have just now noticed that for the M523XEVAL board schematics that A1 is connected to the Flash chip A0 (A2 to A1, etc...).  Have I just done a Boo Boo and will I have to now rewire the address lines such that A0 is not connected to anything, A1 is connected to A0, etc...  And is this why the flash algorithms provided do not work?  I'm thinking now that the processor uses the A0 to get bytes, and since my Flash does not have a BYTE pin, which would normally be connected to A0, there is a screw up whenever the processor tries to access byte data from the 16 bit device.  And this would screw up the flash algorithms provided since they all seem to be based on byte level access.

 

B)  If this be the case why is there not a warning/recommendation in red capital letters that says such.  This is my first time with this processor and 16 bit Flash, I'd assume that A0 is connected to A0.  Nowhere does the MCF523X Reference Manual mention this.

 

THANK YOU, and by the way, if you are able to (PLEASE) help me I have connections with Saint Dogbert and I guarantee that you will be blessed!

 

Dogbert256 

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