Hi,
I am starting work on a project that would require a processor to interact with a custom chip that we have designed and also with a robotic arm. The processor will be programmed to control the robotic arm based on the inputs from the custom chip. The inputs from the custom chip would be required to undergo certain DSP operations and then run some control algos. This will all have to be real-time. I looked at the offerings by ARM and would want to pick one of Cortex-R processors (R4, R5 or R7). I am not sure if something.as powerful as Cortex-A would be needed for this.
Can anyone share their experiences using Cortex series of processors for any similar application that involved real-time DSP so that I can use it as a guiding metric? I would be very grateful.
Thanks
Gaurav
I second Sadanand's response. Control applications typically use a relatively low sample rate (a few kHz) and the M4 has plenty of processing power for this. The Cortex-R and the Cortex-A (and even the recently announced M7) have much more power than you would need.
Another thing to consider is interrupt latency. For control systems its important to keep the input to output latency as low as possible. The M4 interrupt handler has a 12 cycle latency which is phenomenally low. If you use a Cortex-A processor you'll probably use Linux and the latency from the operating system is going to make it unusable. The M4 is a better choice and is easier to program and develop with.