Just to do a quick and dirty comparison of several popular ISAs, I compiled a simple C application that calculates primes using the Sieve of Eratosthenes using the following command: gcc -O2 -c -o prime.o prime.c Then, I compared the output binaries just on memory size using the ELF size Read more…
While work has been under way on our new processor core, which shall remain multi-threaded using interleaved multi-threading in hardware, we have been searching for a free ISA to use as the base instruction set. Our previous microprocessor was based on the Microblaze instruction set (ISA). While there is nothing Read more…
In this post I’ll explain how I debug the new core of AEMB, and the current bug that I’m facing. Debugging the CPU takes place using the demo program originally attached with AEMB. The waveform generated from the demo program running on the new CPU is compared with the waveform Read more…
In the previous post I’ve explained how the threading model of the new AEMB. In this post I will explain all the changes to the old AEMB core that were necessary to accommodate a coarse grained model and sum up with an analysis of how the new threading model affects Read more…
Finally I’ve changed the threading model of the AEMB. While some instructions are still buggy and hence the demo program doesn’t run properly, I still want to use this post and the next one to explain the changes I’ve made so far. In this post I’ll explain about the design Read more…
It is quite amazing how many times I discover myself to have a faulty or shallow understanding about the technology I am working on. Normally those discoveries occur as I go more in depth into the technology at hand. Those two lines are necessary to make up for any faulty Read more…
In this post I’ll continue the in detailed overview of the ISA of AEMB where I’ll review memory access, GET/PUT, special purpose register and program flow instructions. Next I‘ll explain about the data dependencies and how they are currently handled in AEMB. First, there are 12 instructions responsible for memory Read more…
Finally work on the AEMB is to be continued after a long unjustified break. In previous posts I have touched a bit on the Instruction Set Architecture (ISA) of AEMB and explained it’s relation with Microblaze ISA. In order to change the threading model of AEMB to coarse grained, I was warned Read more…
Unfortunately I am still behind schedule as I invested my time this week to analyse the flow of handling branches in AEMB. I had to do this because while I understand the big picture behind the new threading model, I still can’t see the details of it.
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Through out last week I started my preparation for changing the threading model for AEMB.
Software wise, I installed ISE on my Ubuntu to be able to compare the area of AEMB before and after the modifications. Here is a couple of tips for you to avoid making small mistakes during the installation. The first one is to run the installation script as root. Second make sure you have the necessary empty space on your drive before attempting the installation.
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