Using an Assmbly Routine in PBP

[Darrel Taylor]

I'd like to ask which would you most prefer and or convenient with PIC18F data ram addressing "Access Ram" or "Indirect Addressing"

They're really two completely different things.
But if I had to choose one, I'd say "Indirect Addressing".

Access Ram is more for optimizing the code, reducing the size by letting you do things with less bank switching. It doesn't really give any additional functionality.

But "Indirect Addressing" let's you use the entire RAM space like it's a big array, which adds just a TON of functionality. Strings, packets, buffers, software stacks, etc. etc.
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[leisryan]

They're really two completely different things.
But if I had to choose one, I'd say "Indirect Addressing".

Access Ram is more for optimizing the code, reducing the size by letting you do things with less bank switching. It doesn't really give any additional functionality.

But "Indirect Addressing" let's you use the entire RAM space like it's a big array, which adds just a TON of functionality. Strings, packets, buffers, software stacks, etc. etc.
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Wow!!! I really appreciate it really enlightening!!! Is bank switching still occurs in "Indirect Addressing" Un-noticeably though?

[Darrel Taylor]

> Is bank switching still occurs in "Indirect Addressing" Un-noticeably though?

Well, YES and NO.

But, if I had to choose one ...
I'd say NO.

On 18F's, the FSRx registers are 12-bits wide.
Which means it can address any location from 0 to 4095 ($000 to $FFF).
It can access memory locations in ANY BANK without having to change the current bank (BSR). It's just a single address.

The beauty of this, is that no matter what bank your program is currently using, you can read/write from any other bank without switching the banks back and forth. Which may be where your original question was aimed, because Indirect addressing can be a good tool for optimization, much like the Access RAM.