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OMAP3530 Dsplink based application MMU Error - OMAP35x Processors Forum - OMAP™ Processors - TI E2E Community - Iceweasel. Hi, I'm a beginner DSP developer and I'm currently working on some basic filtering applications using the Beagleboard.

OMAP3530 Dsplink based application MMU Error - OMAP35x Processors Forum - OMAP™ Processors - TI E2E Community - Iceweasel

I've managed to build and install dsplink, bios, codec engine, lpm. I've also verified that all the basic example programs work. I'm currently trying to use the LOOP example and instead of having the DSP loop data back to the GPP i'm trying to have receive a buffer of data from the GPP, convolve the buffer with itself and return the convolution result to the GPP.

The main lines of code I've added are #define MAX_SIZE 256 #define ARRAY_SIZE 128 Short buffLocal[MAX_SIZE] Short buffLocal2[MAX_SIZE memset(buffLocal, 0, sizeof(short)*MAX_SIZE) memset(buffLocal2, 0, sizeof(short)*MAX_SIZE) For some reason if MAX_SIZE is larger than 202 the program crashes after the GPP sends the data to the DSP and is awaiting to reclaim the data/channel from the DSP. "DSP MMU Error Fault! The website indicates that by setting mem=80M that I have 48M for DSPLINK. Thanks. FullwaveDelayLowpass - Open Music Labs Wiki - Iceweasel. MICrODEC: Stock Functions Fullwave Distortion with Delay and Lowpass This function implements a fullwave rectifier, with an optional delay and variable cutoff lowpass filter.

FullwaveDelayLowpass - Open Music Labs Wiki - Iceweasel

The input is mono on the left channel, with the direct fullwave signal presented on the right output, and a delayed copy on the left output. The delay is set via the pot (MOD1), and the cutoff frequency is set with the rotary encoder (MOD2). A fullwave rectifier is a simple function which takes all negative input values, and makes them positive. The lowpass filter inside this function allows you to adjust how much of this high frequency noise you want to let through. The pot (MOD1) adjust the delay time, with a range of 0s to 1.5s. Fullwave_delay_lowpass.asm Toggle line numbers. VcoVca - Open Music Labs Wiki - Iceweasel. MICrODEC: Stock Functions This function implements a voltage controlled oscillator (VCO), with the ability to control its amplitude (voltage controlled amplitude - VCA).

VcoVca - Open Music Labs Wiki - Iceweasel

The control voltage is taken from left channel input, and the output is presented on both the left and right channels. The pot (MOD1) set the oscillators base frequency, and the rotary encoder (MOD2) adjusts the functionality of the VCO. In its simplest form, it can be used as a very low distortion audio sine wave generator, which has been extremely useful for us a number of times already. The main oscillator is a sinusoid generated from a look-up table in program memory.

The problem with reading through at faster rates, is that you need samples from points in time when you did not take a sample. The pot (MOD1) adjusts this playback rate from 0Hz all the way to a max value, which is determined by MOD2. The next 8 modes are VCA modes, which means the input on the left channel determines the amplitude of the oscillator.