"accidentally" writing negative values to addr_ptr

Software questions and issues with the FV-1

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knutolai
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Location: Bergen, Norway

"accidentally" writing negative values to addr_ptr

Post by knutolai »

What does the addr_ptr register do with negative values written to it?

Are they clipped, abs() or something else?

"RMPA provides indirect delay line addressing in that the delay line address of the sample to be multiplied
by C is not explicitly given in the instruction itself but contained within the pointer register ADDR_PTR
(absolute address 24 within the internal register file.)"

That's all I can find in the manual.
frank
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Re: "accidentally" writing negative values to addr_ptr

Post by frank »

As this is an absolute address it is not negative or positive, just a value between 0 and 0x7FFF. Any value outside that range will simply be clipped to 15-bits. I.e. if you write 0x8000 it will clip the MSB so it will be address 0x0000.
Frank Thomson
Experimental Noize
knutolai
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Joined: Wed Nov 23, 2016 9:43 am
Location: Bergen, Norway

Re: "accidentally" writing negative values to addr_ptr

Post by knutolai »

Thanks. Ok so kinda like unsigned data. Is this in any way different from a bitwise AND-statement like the one below?

AND 0b0111 1111 1111 1111
frank
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Re: "accidentally" writing negative values to addr_ptr

Post by frank »

Yes, basically the same as ANDing it as you did.
Frank Thomson
Experimental Noize
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