Re: [Caml-list] (Announce) OCAPIC : OCaml for PIC18 microcontrollers
Philippe Wang philippe.w...@lip6.fr writes: Dear all, this is an announcement for OCAPIC, a project which brings OCaml to programming PIC micro-controllers. Some PIC18 series characteristics: - 8 bit architecture - low cost (a few US dollars), fairly spread in electronics world - very low volatile memory (a few bytes only, up to ~5000 bytes, depending on the model) - very low non-volatile memory (less than a KB up to 128 KB) - EEPROM : 0 to 1024 bytes Doesn't the overhead of boxed structures as well as loosing a bit on ints make that impractical given the extremly limited memory? MfG Goswin ___ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
Re: [Caml-list] (Announce) OCAPIC : OCaml for PIC18 microcontrollers
On Nov 6, 2010, at 18:47 GMT+01:00, Goswin von Brederlow wrote: Philippe Wang philippe.w...@lip6.fr writes: Dear all, this is an announcement for OCAPIC, a project which brings OCaml to programming PIC micro-controllers. Some PIC18 series characteristics: - 8 bit architecture - low cost (a few US dollars), fairly spread in electronics world - very low volatile memory (a few bytes only, up to ~5000 bytes, depending on the model) - very low non-volatile memory (less than a KB up to 128 KB) - EEPROM : 0 to 1024 bytes Doesn't the overhead of boxed structures as well as loosing a bit on ints make that impractical given the extremly limited memory? MfG Goswin Thanks for the question. Let me try to give an (indirect) answer. OCAPIC has 16-1=15bit integers and 16bit blocks. And the overhead is quite acceptable to us. A gobblet game [1] I.A. was implemented and tested. (The OCaml code is included in the distribution so anyone can check it out.) The first version of this game was very hard to beat (for a human). Then a strategy was found (to beat the I.A.). So some randomization was supplied to the I.A. to make it more interesting. Now the I.A. has become really very hard to beat. (We used a PIC18F4620: flash memory = 64kiB; volatile memory = 3968B ; EEPROM = 1KiB ; speed = 10 MIPS) Between two moves, the I.A. may trigger the GC about ten times or more. However, the time between two moves is less than 2 seconds, and generally quite less than half a second (and in the beginning of the game it's hard to realize the time it takes). Providing a GC to programming PIC microcontrollers is a tremendous gain comparing to manually manage everything (memory and computing). Providing a high-level language allows to implement algorithms that would be very hard or impossible to implement in ASM (or most low-level languages such as C or Basic). We haven't yet experimented real-time constrained programming (e.g., ReactiveML might bring OCAPIC to a step further). Now, maybe the direct answer to the question can be : programming PICs has been impractical to most people, now all readers of this list can potentially program them without much difficulties (and without paying a too high cost on performance efficiency). :-) [1] http://www.educationallearninggames.com/how-to-play-gobblet-game-rules.asp Cheers, -- Philippe Wang philippe.w...@lip6.fr http://www-apr.lip6.fr/~pwang/ ___ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
[Caml-list] ocamlnet: event queues
Hello, still in my first cut at rpc, in my app I need to react on a file descriptor collectings logs for a child process, how do I transform let esys = Unixqueue.standard_event_system () in let server = Deconv_srv.Rpc_control.V1.create_server ~proc_connect: connect ~proc_set_input: set_input ~proc_set_deconvolution: set_deconvolution (Rpc_server.Localhost 2345) Rpc.Tcp Rpc.Socket esys in Unixqueue.run esys to something where I can add an fd to the poll/select, and know which fd has triggered one run of the loop? I did found Netsys_pollset.pollset.add fd browsing the doc, but writing a custom run() is another matter. Thaaanks a lot. ___ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
Re: [Caml-list] ocamlnet: event queues
On Sat, Nov 6, 2010 at 3:43 PM, Philippe Strauss phi...@philou.ch wrote: still in my first cut at rpc, in my app I need to react on a file descriptor collectings logs for a child process, how do I transform let esys = Unixqueue.standard_event_system () in [...] Unixqueue.run esys to something where I can add an fd to the poll/select, and know which fd has triggered one run of the loop? If I understand you correctly, you just want to watch an additional file descriptor and react when it becomes readable. You can do that by adding the fd to the event system with Unixqueue.add_resource, then attaching a handler for when the fd becomes readable with Unixqueue.add_handler. See the docs at http://projects.camlcity.org/projects/dl/ocamlnet-3.0.2/doc/html-main/Unixqueue.html for more details. Jake ___ Caml-list mailing list. Subscription management: http://yquem.inria.fr/cgi-bin/mailman/listinfo/caml-list Archives: http://caml.inria.fr Beginner's list: http://groups.yahoo.com/group/ocaml_beginners Bug reports: http://caml.inria.fr/bin/caml-bugs
