denny george

Code execution(Address Bus  And  DATA Bus  Access) during FLASH Erase HCS908

Discussion created by denny george on Mar 5, 2008
Latest reply on Mar 6, 2008 by David Payne
Hello All,
 
In HCS908AW32, We have an flash erase time of 20 ms for a single page of 512bytes.Single page (512B) is the minimum possible erasable flash area.I cannot erase anything less than this num of bytes.
 
 
 
Now my doubt is that during this erase time (i.e. after the erase command has been issued) for the next 20 ms should I wait there indefinitely till FLASH Command Complete Flag is SET or can I do anything useful like executing some critical code.
 
If I wait till 20ms some of my critical code could not be executed(to be frank some data coming from outside into the micro) I'll miss this event.
 
Is the address/data bus locked during this period? If not Then I think I can execute code from RAM.(Code cannot be run from flash while flash erase/programming are to be done right? )
 
Also I have noticed sometime back while flash erasing/programming, an  access to the flash part of the code creates reset in HC908GR32.But in HCS908AW32 if I access the operation was getting affected.
 
AW32 data sheet documentation is really poor. Have anyone had previously run any code during this erase period  or any valuable suggestions for me ???
 
 
Best Regards,
Denn

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