Alloc 16b sdram Object

#1

Can anyone tell me how this object is used? I'm particularly interested in what the 'init' attribute is for. I can't work it out from looking at the object code, and the description isn't very enlightening...

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#2

The init attribute lets you write a bit of code which gets run when the module initializes, see attr_init in the init section. The typical use of the init code attribute would be be to fill the allocated table with some values.

The module is a general table that can be referenced by name and read/written from other modules, like you do with delay write and read modules.

#3

Ah, that makes sense.
I saw the reference to 'attr_init', but didn't realise that meant 'run init string as code'.

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#4

Sorry, silly question, but how would an init function get a handle on the SDRAM array, in order to load data into it?

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#5

Sorry, answered my own question, looking at the help patch for the object.

int i;
for(i=0;i<LENGTH;i++)
	array[i]=(1<<21)*i;

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#6

Is it possible to define and init an array like

int16_t array[length] = {val0, val1, etc.};

I'm attempting to do the above with the 8b version of the object, but it seems to take a reallllly long time to compile, when going live, and also doesn't seem to work - i.e. I don't seem to be able to extract any values from the array using a table read object.

Could anyone take a look at the attached, and tell me if I'm doing anything silly.

TableAllocRead_test01.axp (84.2 KB)

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#7

You have to do the combined declaration and init in Local Data as far as I can tell. I'm doing it this way for my NES objects I am working on, but they're just initialised with static lookups.

#8

Hmm.. can't get this to work at all, currently.
I think I'll ask in the Object Coding thread, as it's looking like this is going to have to be a custom object, now.

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