blob: cff60f73e1624c83c66adcf23f1f3e1c9f2c51a4 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
|
package org.broeuschmeul.android.gps.sirf.util;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.util.Formatter;
import java.util.Locale;
public class SirfUtils {
private static final String start ="A0A2";
private static final String end ="B0B3";
public static byte[] genSirfCommand(String commandHexa){
int length = commandHexa.length()/2;
ByteBuffer command = ByteBuffer.allocate(length);
command.put(new BigInteger(commandHexa,16).toByteArray(), 1,length);
return command.array();
}
public static byte[] genSirfCommandFromPayload(String payload){
String commandHexa = createSirfCommandFromPayload(payload);
return genSirfCommand(commandHexa);
}
public static String createSirfCommandFromPayload(String payload){
int length = payload.length()/2;
String res;
byte[] command = new BigInteger(payload,16).toByteArray();
int checkSum = 0;
for (byte b : command){
checkSum += (b & 0xff);
}
checkSum &= 0x7FFF;
res = String.format((Locale)null, "%s%04X%s%04X%s", start, length, payload, checkSum, end);
return res;
}
public static String showSirfCommandFromPayload(String payload){
byte[] command = genSirfCommandFromPayload(payload);
StringBuilder out = new StringBuilder(payload.length()+16);
Formatter fmt = new Formatter(out, null);
for (byte b : command){
fmt.format("%02X", b);
}
return out.toString();
}
}
|
