[tremor] Minimum hardware requirements

[Segher Boessenkool]

Jerry Durand wrote:
> At 09:16 PM 1/29/2003, you wrote:
> 
>> Johnny Egeland wrote:
>> >
>> > - Minimum amount of RAM needed for decoding (excluding anything that 
>> can be
>> > stored in static lookup tables).
>>
>> DRAM?  Just get 4MB or so, dram is cheap.
> 
> 
> Not all DSPs support DRAM.  That's an extravagance for the higher end 
> ones.  DRAM is also WAY slow for a DSP.  It's like using floppy disks on 
> a PC (good for storing things that you don't need often).

Most dsp's have builtin sram; the dram would be for buffering
(or would you actually buy a meg or more of sram just for that?)

For current Vorbis streams, 20 kwords or so of sram should be
enough to do the decoding.  But you still need to buffer.

>> > - Minimum amount of program memory (ROM) needed to hold the decoder
>> > (estimates are fine). I'm most interested in knowing the size of 
>> only the
>> > decoding part of Tremor.
>>
>> Minimum?  16kB or so.  But then again, flash is cheap, too, so just get
>> 128kB or more.
> 
> 
> They don't make 10nS FLASH, so all us DSP guys have to copy the code to 
> SRAM to run it.  So, we really DO care about the amount of memory.  In 
> one of my typical designs, the SRAM draws 5X or more power than the DSP 
> and costs more, too.

Surely you don't keep all of the program in sram at all time?

<p>Segher

<p>--- >8 ----
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