cocoa - How to build commands for use with writeAsync over RFCOMMChannel? -


i have communicate on bluetooth device, device expects commands separated carriage return + linefeed. connection established using rfcommchannel.

atm seems code not working since expecting reply device, when send commands using simpel terminal program.

this code run after connection established (this definately working since can log data coming in external device)

nsstring *clockrequest = @"c\r\n"; void *clockrequestdata = (__bridge void *)([clockrequest datausingencoding:nsasciistringencoding]);  nslog(@"data buffer write: %@", clockrequestdata);  [rfcommchannel writeasync: clockrequestdata length:100 refcon:null];   //writing data rfcomm - (void)rfcommchannelwritecomplete:(iobluetoothrfcommchannel*)rfcommchannel refcon:(void*)refcon status:(ioreturn)error {      nslog(@"macbook wrote timecube, status: %d", error); }

the code establishing connection taken , adjusted https://gist.github.com/crazycoder1999/3139668

thx in advance

add category nsstringhextobytes project:

nsstring+nsstringhextobytes.h

#import <foundation/foundation.h>  @interface nsstring (nsstringhextobytes) + (nsdata *)datawithstring:(nsstring *)string; @end

nsstring+nsstringhextobytes.m

#import "nsstring+nsstringhextobytes.h"  @implementation nsstring (nsstringhextobytes)  + (nsdata *)datawithstring:(nsstring *)string {     //string = [string stringbyreplacingoccurrencesofstring:@"0x" withstring:@""];      //nscharacterset *notallowedcharacters = [[nscharacterset charactersetwithcharactersinstring:@"abcdefabcdef1234567890"] invertedset];     //string = [[string componentsseparatedbycharactersinset:notallowedcharacters] componentsjoinedbystring:@""];      const char *cstring = [string cstringusingencoding:nsasciistringencoding];     const char *idx = cstring;     unsigned char result[[string length] / 2];     size_t count = 0;      for(count = 0; count < sizeof(result)/sizeof(result[0]); count++)     {         sscanf(idx, "%2hhx", &result[count]);         idx += 2 * sizeof(char);     }      return [[nsdata alloc] initwithbytes:result length:sizeof(result)]; }  @end

in implementation file import nsstring+nsstringhextobytes.h , add method

-(void)sendmessage:(nsdata *)data {     [rfcommchannel writesync:(void*)data.bytes length:data.length]; }

and then:

nsstring* clockrequest = @"c\r\n"; nsdata* data = [nsstring datawithstring:clockrequest]; [rfcommchannel sendmessage:data];

Comments

Post a Comment

Popular posts from this blog

jquery - How can I dynamically add a browser tab? -

since using iframes house external pages are, accounts "not preferred method" , disallowed sites (flickr, one), want dynamically generate browser tabs. e.g., when user submits form, want dynamically generate tab on browser in response submitted. e.g., might want add new tab url like: http://www.bigsurgarrapata.com/contact how in jquery? you want form target attribute action attribute. http://www.w3schools.com/tags/att_form_target.asp browsers have ultimate control on result of target attribute open new tab value of _blank. <form action="contact_submit.php" target="_blank" method="post">
Read more

keyboard - C++ GetAsyncKeyState alternative -

i using windows.h library's getasynckeystate function define key pushed on keyboard . here program returns int value of pushed key example. #include <iostream> #include <windows.h> using namespace std; int main (){ char i; for(i=8;i<190;i++){ if(getasynckeystate(i)== -32767){ cout<<int (i)<<endl; } } return 0; } but trying make opengl simple game , function appeared slow . there function not need cycle 180 times , if statement . thanks you're trying make opengl game, you're going use glfw. if that's case can away using glfwgetkey() such: if (glfwgetkey(glfw_key_up) == glfw_press) {...} if (glfwgetkey(glfw_key_down) == glfw_press) {...} that method nicely explained in tutorial 6 opengl-tutorial.org . should start first tutorial of beginners tutorials , later intermediate tutorials . if you're going make win32 window can listen wm_keydown or wm_keyup messages , virtua...
Read more

android - java.net.UnknownHostException(Unable to resolve host “URL”: No address associated with hostname) -

i developing app testing asp.net webservice in android.for simple webservice adding 2 numbers used.where numbers passed parameters.the result in dialogue.the webserver works in local. when application runs following result exception.i provided internet permission in manifest. java.net.unknownhostexception(unable resolve host “ http://url.com/ ”: no address associated hostname) my code given below main activity public static string rslt=""; /** called when activity first created. */ @override public void oncreate(bundle savedinstancestate) { super.oncreate(savedinstancestate); setcontentview(r.layout.activity_main); button b1=(button)findviewbyid(r.id.button1); final alertdialog ad=new alertdialog.builder(this).create(); b1.setonclicklistener(new onclicklistener() { @override public void onclick(view arg0) { // todo auto-generated method stub try { ...
Read more