scope of digital signal controllers

[einton]

guys i m amazed by the feature of DSC , i go little through dSPIC33F datasheet it quite nice but i m thinking what are the places it can replace microcontroller , i dont find any about it. any particular advantage any one explain.

secondly is there any way to build its programmer.

 

[Sceadwian]

They're not used for the same things einton, given price and overall complexity they will not replace micro controllers, because they are in fact NOT micro controllers =) They're DSP's. Different devices not really comparable.

**broken link removed**
May provide some insight on programming.

 

[Oznog]

They're not used for the same things einton, given price and overall complexity they will not replace micro controllers, because they are in fact NOT micro controllers =) They're DSP's. Different devices not really comparable.

**broken link removed**
May provide some insight on programming.

This is completely wrong, in the case of the dsPIC33F anyways. It is not only a uC, it's a very powerful and useful one.

The 33F calls itself a "DSP" because it uses 16 bit math, 16 bit Working Registers (at some points, 32 bit even!), a 40 bit Accumulator, "fractional" math mode, and a number of core instructions which work very well with DSP problems, in particular the FIR. EVERYTHING in the DSP core CAN be done with a PIC18F, it'll just be far less efficient and it may be impossible to meet performance goals.

The FIR for example is a repeat of a multiply 16*16, add the result to a 40 bit Accumulator, preload the next 2 arguments from file registers into Working registers, and increment those file register counters. All that's a repeat of ONE instruction on a dsPIC, and only needs one cycle! The 18F can do this, but it might take 50 cycles, or maybe far more if written in C. If the 10 MIPs clock of an 18F won't be able to do the job with this long-code solution, then the 18F can't do the job.

None of the DSP core ops are invoked by standard C math. Any attempt to code this FIR calculation solution in C for the 33F will make a very inefficient solution which won't use the DSP core. The FIR calculator can be done by calling ASM from C (very easy!) or just using the FIR task from the language lib, that is a C task coded in ASM and prebuilt.

You can use the 33F for its low power, high speed capabilities and 16bit math/DMA/advanced peripheral features without ever using the DSP core. Also they often come with very large RAM (but, be warned, the 33F has no EEPROM). It's very capable. However, the 24F is a slightly cheaper line of the same thing without the DSP. If you don't need the DSP core, you can go 24F.

 

[einton]

thanx guys u have provided max effort that one can provide , but can u please tell what areas it covers especially when u talk about control industry i have witnessed it application in motor control , any other area other than signal processing.

 

[spindrah]

what are you asking?

the Dspics are like Pics but with extra instructions for things like FFT and ...

 

[Sceadwian]

einton, the applications are pretty far reaching. Audio and image manipulatioin, control systems, communication, etc.. etc.. Depends on the needs of the application and the capabilities of the device.

 

[einton]

thanx to all but can any one telll which are the most basic and which are most capable /featured devices

 

[spindrah]

thanx to all but can any one telll which are the most basic and which are most capable /featured devices

OK I'll try and answer this.

the chips with MORE features are the most capable/featured devices.
the chips with LESS features are the most basic devices.

I hope that I have cleared up your misunderstanding, but if i have not please try and ask your question better.

 

[Oznog]

thanx to all but can any one telll which are the most basic and which are most capable /featured devices

Go on Microchip's website. Bring up the 33F product line and sort by price. The most expensive is the most featured...

All the 33F have the same instruction core. Some have more RAM than others. They have different peripherals... What do you actually want to do?