Diff: DS2.h

Revision:

0:32d3cc3791c4

diff -r 000000000000 -r 32d3cc3791c4 DS2.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DS2.h	Fri May 20 16:54:39 2011 +0000
@@ -0,0 +1,116 @@
+#ifndef DS2_H
+#define DS2_H
+
+#include "mbed.h"
+
+#include "Bus.h"
+
+extern Serial dbg;
+
+#define DS2_MTU (127)
+
+static const char DS2_IDENTIFY[] = {0x00};
+
+/*
+a ds2 packet looks like this:
+{0xAA, 0xAA, 0xLL, 0xDD, 0xCC}
+or this:
+{0xAA, 0xLL, 0xDD, 0xCC}
+AA = module address
+LL = packet length
+DD = data
+CC = checksum
+there can be either one or two AA module address bytes
+there can be 1 or more DD data bytes
+
+here is an example query packet:
+{0x12, 0x04, 0x00, 0x16} (query DME for identification)
+the address is a one-byte address of 0x12 (DME)
+the packet length is 0x04 bytes
+the one byte data payload is 0x00 (identify module)
+the xor checksum of the entire packet is 0x16
+
+the reply would look like this:
+{0x12, 0x10, ... 0x??} (DME responding...)
+the one byte address is 0x12 (DME)
+the packet length will be 0x10 bytes
+the xor checksum 0x?? would depend on the missing data "..."
+
+the same query packet would look like this with two address bytes:
+{0x12, 0x00, 0x05, 0x00, 0x17}
+
+it seems that some modules want one address byte and some want two
+either that or it's an extra length byte we're dealing with
+probably it's a length byte, but I'll worry about it when I find out
+*/
+class DS2Packet
+{
+    unsigned short* address;
+    char* length;
+    char* data;
+    char* checksum;
+    
+    char* rawdata;
+    bool has8BitAddr;
+
+    void updateChecksum();
+    
+public:
+    DS2Packet(int maxlength);
+    DS2Packet(int address, const char* data, int length);
+    ~DS2Packet();
+    
+    void has8BitAddress(bool b);
+    
+    bool has8BitAddress()
+    {
+        return has8BitAddr;
+    }
+    
+    int getAddress()
+    {
+        if(has8BitAddr)
+            return *address >> 8 & 0xff;
+        return *address;
+    }
+    
+    int getLength()
+    {
+        return *length;
+    }
+    
+    char* getData()
+    {
+        return data;
+    }
+
+    int getChecksum()
+    {
+        char* check = rawdata + *length - 1;
+        return *check;
+    }
+    
+    char* getRawData()
+    {
+        return rawdata;
+    }
+};
+
+class DS2
+{
+    Bus *k;
+    Bus *l;
+    
+public:
+    DS2(Bus* KLine, Bus* LLine);
+    ~DS2();
+    int sendPacket(DS2Packet* packet, Bus* bus);
+    DS2Packet* getPacket(Bus* bus);
+    DS2Packet* getPacket8(Bus* bus);
+    bool test();
+    void testModule(int address);
+    void snoop();
+
+};
+
+#endif //DS2_H
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