Microblaze and PowerPC

[am85]

Hi,
I would like to perform mathematical operations as Division and Square root. From what i have read, i either need to use Microblaze or PowerPC. can anyone please tell me the difference in performance between them, and is it a hardware or software calculation. Does each one of these options has a dedicated FPU?

Thanks in advance.

 

[bigdogguru]

The requirements of division and square root do not necessitate the implementation or use of a softcore or hardcore processor. It depends more on the overall project's performance and throughput requirements, IP cores for both division and square root do exist and presence of a CPU may or may not impact its overall success.

Here's a brief comparison of Microblaze Softcore and PowerPC Hardcore features:



One true advantage of the Microblaze, is its powerful flexibility and design customization. If you need two of Microblaze cores, it's not a problem as long as you have the square footage available on your FPGA.

Ciao

 

[permute]

division and square root are more complex then multiplication. Most other operations are also more complex. (erf, e^x, atan, ln). These operations typically are done in multiple cycles, possibly with pipelining for high performance. both xilinx and altera have IP cores for division and square root.

 

[am85]

Thanks for your reply. Actually I have to use a processor anyway coz i am using Ethernet, CAN, SPI and USB cores, which requires a processor for simpler control. Therefore, i considered using the Microblaze or PowerPC for the mathematical operations. from what I understand using the hard processor PowerPC will achieve a much higher speed than the soft processor Microblaze, or is the FPU of Microblaze a hardware operation?

 

[bigdogguru]

Well let me first ask you a question, what are you willing to pay for the Xilinx FPGA with an embedded PowerPC?

For example Xilinx XC5VFX Series range from $500 to $10,000 for just the FPGA, that's not a development board. And the gate count on the $500 entry level unit is nothing to brag about, 30K.

You can pickup a very nice Spartan 3E development board with all those peripherals you mentioned from Digilent, Inc. for just a couple hundred dollars:



And it supports the Xilinx EDK and Microblaze.

But if money's no object, I say go for it!

Virtex-5 FXT ML510 Embedded Development Platform

I'll have to ordering the ML510 if I win the bid for contract job, only $4000, Development Software not included, that's another $1500.

 

[am85]

I thought I could get a Virtex 4 with PowerPC with gate count sufficient for all these cores for less than $1000. I want to perform effective voltage and current calculations of an analog signal, but the ADC is on an external ASIC. I was thinking these calculations will require the speed of PowerPC rather than Microblaze. Can you please tell me if the FPU of Microblaze is a hardware operation or not and its performance compared with PowerPC.