Post by thread:[PICLIST] ASM vs C or PBP

I have used PBP on some projects but find ASM rather easy and MUCH more efficient use of memory space. Has anyone compaired the space required for a given task when using some of the C compilers? Rich -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email spam_OUTlistservTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body

On Thu, 1 Mar 2001, Richard Clemens wrote: > I have used PBP on some projects but find ASM rather easy and MUCH more > efficient use of memory space. Has anyone compaired the space required for > a given task when using some of the C compilers? I have not coded the exact same task in ASM and C to compare side by side, but I suspect that overall it's probably within a few percent assuming enough code for a valid comparison. For me anyway. Big difference is in development time and maintainability (again, for me). Now, you get someone like Bob, or Scott, or Nikolai writing the ASM code and all bets are off - but I can't write ASM code like they do even on my best days. Dale --- The most exciting phrase to hear in science, the one that heralds new discoveries, is not "Eureka!" (I found it!) but "That's funny ..." -- Isaac Asimov -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email .....listservKILLspam@spam@mitvma.mit.edu with SET PICList DIGEST in the body

I have used all three. PBP requires you keep track of all variables and uses macros which result in .ASM files that are very difficult to debug. Not, to spark a big flame war, but I use the $99 CCS PCM compiler, but avoid all of the built in functions and have been pleased. I just don't think I can clearly write the code in .ASM and do as well as the C compiler. There are exceptions and it pays to know assembly for those situations. I would guess my development time is 10 percent of what it would be with assembly. I really resisted C on the 12C508 as it just seemed as if the chip was too too small. But, again, using CCS PCB, I was pleasantly surprised. Peter H. Anderson, http://www.phanderson.com, pha(at)phanderson.com Sign up for Free-for-Life E-mail at http://www.Africana.com -- http://www.piclist.com hint: To leave the PICList piclist-unsubscribe-requestKILLspammitvma.mit.edu

> but I suspect that overall it's probably within a few percent assuming Well it many percent for PBP ... so what is the best C --> PIC compiler... I define best as the one that produces the tightest best code with relative ease without regard to price. -- Richard Clemens .....clemensKILLspam.....wvwc.edu {Original Message removed}

On Fri, 2 Mar 2001, Richard Clemens wrote: > > but I suspect that overall it's probably within a few percent assuming > > Well it many percent for PBP ... so what is the best C --> PIC compiler... > I define best as the one that produces the tightest best code with relative > ease without regard to price. Andrew Warren, John Payson, Dmitry, Nik, Bob, myself, and many others placed into a room (preferably in some place like Hawaii - since Price is no object), will produce the absolute best C to pic assembly. It would be slow and expensive, however. On a more practical level, there is Byte Craft and HiTech. Everything else just doesn't compare (including my work on SDCC). -- http://www.piclist.com hint: To leave the PICList EraseMEpiclist-unsubscribe-requestspam_OUTTakeThisOuTmitvma.mit.edu

This just occurred to me so I'll throw it in since I haven't seen it suggested. First of all I usually look at what the compiler (mine's CCS) generates for a line of C and I'm usually impressed that it's pretty straightforward (that means I was able to understand it :) So I'll go along with the "few percent bigger" conjecture. But my C code is always larger. Why? Because coding in assembler is so intricate that I often resist adding a feature here and there or a "superfluous" double-check on a value. In C such lines are easy to add and I know I won't be hand stepping past the BTFSS to see if I got it the wrong way again... Barry -- http://www.piclist.com hint: To leave the PICList piclist-unsubscribe-requestspam_OUTmitvma.mit.edu