Darth Gazak said:
Little off topic here, but i have a question directed at Firefox and Exophase; How did you learn all this information about programming and processors etc?
I'm thinking of doing computer science at university, and was wondering whether any of you had went through a similar course.
Thanks
I started learning about programming and processors on my ZX81 and later ZX Spectrum in the early 1980s. Being a kid and having a real computer of your own was an amazing thing back then, so just the wonder of it all made me barricade myself in my room the Xmas I got my '81 and work through the BASIC programming manual that came with it from cover to cover.
I learned machine code a couple of years later when I got my Spectrum (not assembly language; I didn't have enough pocket money saved up to afford an assembler to begin with so I used to write my code on squared paper and write the machine code in hex next to it, including calculating the relative jumps. Bloody good experience, that.) That was my first taste of processors, though the old Z80 is very different from modern RISC processors.
At uni at the start of the 90s I did a hardcore electrical engineering/control engineering degree. In the final year we had to design a 4-bit microprocessor as our final year project for digital electronics - it had to fit inside 1000 gate equivalents, and we had to "hand wire" them on a primitive CAD program on our lab workstations. Sadly they didn't have the budget to get them made in real silicon that year, but that was the most interesting project I did at uni by a mile. I spent ages trying different schemes for the instruction set encoding and optimising the sequencing logic, then going back to tweak the instruction set so I could reduce the number of gates in the design (done with pencil and paper, since time on the lab workstations was limited and the CAD program was a pain in the arse to use).
While I was at uni I had an Atari STE that I did a lot of extracurricular coding on (most students had a 286-based PC running DOS), and we had 68000-based targets to program in our software engineering labs. So I ended up doing quite a lot of 68000 programming at uni, on top of C programming which is what I used for everything else.
Also, it was a very exciting time in microprocessor design, there were all sorts of advances being made. I used to pore over the articles on the latest processors in magazines like Byte and also ransack the library for papers on processor design - this being a little before the internet really took off.
I don't know what I'd recommend for learning about microprocessors nowadays... Probably get yourself a nice emulator that has a bit of a debugger built in, like VisualBoyAdvance perhaps. That way you can get load your code into the emulator instantly and step through it in the debugger and see immediately what happens to registers, how the flags affect the program flow, and so on.
Exophase said:
If you do end up interested let me know some time.
One question that immediately springs to mind: How do run generating code inside a Linux process?
I've got a feeling there's a bit more to it to writing your opcodes into a word-aligned array, casting a pointer to it into a function pointer, and then calling it... :unsure:
