[Simulavr-devel] SPM temp buffer

[ken restivo]

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Ted-

Since I'm testing and debugging a bootloader, I have run into a situation where 
I need to implement and the the SPMCR register.

So far so good, adding all the conditionals to avr_opcode_SPM() was easy, and 
adding SPMCR to register.c is going to be pretty straightforward.

However, one thing I'm not sure of is where in the object-oriented structure of 
things to add the "temporary page buffer" mentioned in the databook? It's a 
buffer of 128 bytes on the atmega163, and I can only guess it's some in-chip 
reserved sram.

The databook implies that this is stored SOMEWHERE, but it appears not to be be 
in actual application-addressable sram. I haven't yet tried writing test data 
tosram after first spm'ing stuff into the "temporary buffer", to see if/where 
it is stored, but I imagine it isn't in there anyway, since the databook offers 
no stern admonisments against writing to sram during/between these operations.

I'm inclined to do the quick hack and just avr_malloc() 128 bytes inside of the 
SPMCR constructor, and leave it at that. But if there's a better place to put 
this thing, let me know.

Cheers!

- -ken
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