Создание объекта данных

Question

Мне нужно отправить данные на последовательный порт. Определение того, что к передаче:

Chr$(2) = Clear buffer 
Chr$(48)&Chr(57) = Any number between 0 to 359 

Моя неудачная попытка с вводом 2090

int i, c; 
char j; 
NSString *tmpStr = [self.sendTextField stringValue]; 
NSString *tmpVal; 
for (i = 0 ; i < [tmpStr length]; i++) 
{ 
    NSLog(@"Iteration: %d", i); 
    tmpVal = [tmpStr substringWithRange:NSMakeRange(i, 1)]; 
    c = [tmpVal intValue]; 
    j = (char)c; 
    tmpVal = [NSString stringWithFormat:@"%c", j]; 
    NSData *dataToSend = [tmpVal.value dataUsingEncoding:NSUTF8StringEncoding]; **<Error here** 
    [self.serialPort sendData:dataToSend]; 
} 

Я не знаю, как исправить ошибку отчетов консоли.

2013-03-08 10:38:12.430 ORSSerialPortCocoaDemo[40656:303] Iteration: 0 
2013-03-08 10:38:38.819 ORSSerialPortCocoaDemo[40656:303] -[__NSCFString value]: unrecognized selector sent to instance 0x1001626a0 
2013-03-08 10:38:38.819 ORSSerialPortCocoaDemo[40656:303] -[__NSCFString value]: unrecognized selector sent to instance 0x1001626a0 
2013-03-08 10:38:38.821 ORSSerialPortCocoaDemo[40656:303] (
0 CoreFoundation      0x00007fff858180a6 __exceptionPreprocess + 198 
1 libobjc.A.dylib      0x00007fff835b03f0 objc_exception_throw + 43 
2 CoreFoundation      0x00007fff858ae6ea -[NSObject(NSObject) doesNotRecognizeSelector:] + 186 
3 CoreFoundation      0x00007fff858065ce ___forwarding___ + 414 
4 CoreFoundation      0x00007fff858063b8 _CF_forwarding_prep_0 + 232 
5 ORSSerialPortCocoaDemo    0x0000000100008e81 -[ORSSerialPortDemoController send:] + 465 
6 AppKit        0x00007fff868d6a59 -[NSApplication sendAction:to:from:] + 342 
7 AppKit        0x00007fff868d68b7 -[NSControl sendAction:to:] + 85 
8 AppKit        0x00007fff868d67eb -[NSCell _sendActionFrom:] + 138 
9 AppKit        0x00007fff868d4cd3 -[NSCell trackMouse:inRect:ofView:untilMouseUp:] + 1855 
10 AppKit        0x00007fff868d4521 -[NSButtonCell trackMouse:inRect:ofView:untilMouseUp:] + 504 
11 AppKit        0x00007fff868d3c9c -[NSControl mouseDown:] + 820 
12 AppKit        0x00007fff868cb60e -[NSWindow sendEvent:] + 6853 
13 AppKit        0x00007fff868c7744 -[NSApplication sendEvent:] + 5761 
14 AppKit        0x00007fff867dd2fa -[NSApplication run] + 636 
15 AppKit        0x00007fff86781cb6 NSApplicationMain + 869 
16 ORSSerialPortCocoaDemo    0x0000000100001d62 main + 34 
17 ORSSerialPortCocoaDemo 

Answer 1

Удалить вызов к value метода:

NSData *dataToSend = [tmpVal dataUsingEncoding:NSUTF8StringEncoding];