More RFCOMM layer implementation - fix FCS calculation, add in start of control chann...

diff --git a/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c b/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c
index e69a27e..5a7edc2 100644 (file)
--- a/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c
+++ b/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.c
@@ -74,18 +74,18 @@ void RFCOMM_ProcessPacket(void* Data, Bluetooth_Channel_t* const Channel)
        /* Decode the RFCOMM frame type from the header */
        switch (FrameHeader->Control & ~FRAME_POLL_FINAL)
        {
-               case RFCOMM_Frame_SABM:
-                       RFCOMM_ProcessSABM(FrameHeader, Channel);
-                       break;
-               case RFCOMM_Frame_UA:
-                       RFCOMM_ProcessUA(FrameHeader, Channel);
-                       break;
                case RFCOMM_Frame_DM:
                        RFCOMM_ProcessDM(FrameHeader, Channel);
                        break;
                case RFCOMM_Frame_DISC:
                        RFCOMM_ProcessDISC(FrameHeader, Channel);
                        break;
+               case RFCOMM_Frame_SABM:
+                       RFCOMM_ProcessSABM(FrameHeader, Channel);
+                       break;
+               case RFCOMM_Frame_UA:
+                       RFCOMM_ProcessUA(FrameHeader, Channel);
+                       break;
                case RFCOMM_Frame_UIH:
                        RFCOMM_ProcessUIH(FrameHeader, Channel);
                        break;
@@ -95,12 +95,29 @@ void RFCOMM_ProcessPacket(void* Data, Bluetooth_Channel_t* const Channel)
        }
 }
 
+static void RFCOMM_ProcessDM(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel)
+{
+       BT_RFCOMM_DEBUG(1, "<< DM Received");
+       BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameHeader->Address.DLCI);
+}
+
+static void RFCOMM_ProcessDISC(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel)
+{
+       BT_RFCOMM_DEBUG(1, "<< DISC Received");
+       BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameHeader->Address.DLCI);
+
+       // TODO: Close down connection
+
+       BT_RFCOMM_DEBUG(1, ">> UA Sent");
+       RFCOMM_SendFrame(FrameHeader->Address.DLCI, true, (RFCOMM_Frame_UA | FRAME_POLL_FINAL), 0, NULL, Channel);
+}
+
 static void RFCOMM_ProcessSABM(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel)
 {
        BT_RFCOMM_DEBUG(1, "<< SABM Received");
        BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameHeader->Address.DLCI);
        
-       // TODO: Reset channel send/receive state here
+       // TODO: Reset channel send/receive state
        
        BT_RFCOMM_DEBUG(1, ">> UA Sent");
        RFCOMM_SendFrame(FrameHeader->Address.DLCI, true, (RFCOMM_Frame_UA | FRAME_POLL_FINAL), 0, NULL, Channel);
@@ -108,34 +125,25 @@ static void RFCOMM_ProcessSABM(const RFCOMM_Header_t* const FrameHeader, Bluetoo
 
 static void RFCOMM_ProcessUA(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel)
 {
-       const uint8_t* CurrBufferPos = ((const uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t));
-
        BT_RFCOMM_DEBUG(1, "<< UA Received");
-       BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address);
-}
-
-static void RFCOMM_ProcessDM(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel)
-{
-       const uint8_t* CurrBufferPos = ((const uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t));
-
-       BT_RFCOMM_DEBUG(1, "<< DM Received");
-       BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address);
-}
-
-static void RFCOMM_ProcessDISC(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel)
-{
-       const uint8_t* CurrBufferPos = ((const uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t));
-
-       BT_RFCOMM_DEBUG(1, "<< DISC Received");
-       BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address);
+       BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameHeader->Address.DLCI);
 }
 
 static void RFCOMM_ProcessUIH(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel)
 {
-       const uint8_t* CurrBufferPos = ((const uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t));
-
        BT_RFCOMM_DEBUG(1, "<< UIH Received");
-       BT_RFCOMM_DEBUG(2, "-- Address 0x%02X", FrameHeader->Address);
+       BT_RFCOMM_DEBUG(2, "-- DLCI 0x%02X", FrameHeader->Address.DLCI);
+       
+       uint8_t* FrameData    = (uint8_t*)FrameHeader + sizeof(RFCOMM_Header_t);
+       uint16_t FrameDataLen = RFCOMM_GetFrameDataLength(FrameData);
+       FrameData += (FrameDataLen < 128) ? 1 : 2;
+       
+       BT_RFCOMM_DEBUG(2, "-- Length 0x%02X", FrameDataLen);
+       
+       if (FrameHeader->Address.DLCI == RFCOMM_CONTROL_DLCI)
+       {
+               // TODO: Process control command
+       }
 }
 
 static void RFCOMM_SendFrame(const uint8_t DLCI, const bool CommandResponse, const uint8_t Control, const uint16_t DataLen, const uint8_t* Data,
@@ -170,38 +178,38 @@ static void RFCOMM_SendFrame(const uint8_t DLCI, const bool CommandResponse, con
        /* Copy over the packet data from the source buffer to the response packet buffer */
        memcpy(ResponsePacket.Data, Data, DataLen);
        
+       /* Determine the length of the frame which is to be used to calculate the CRC value */
+       uint8_t CRCLength = sizeof(ResponsePacket.FrameHeader);
+
+       if ((Control & ~FRAME_POLL_FINAL) != RFCOMM_Frame_UIH)
+         CRCLength += sizeof(ResponsePacket.Size);
+       
        /* Calculate the frame checksum from the appropriate fields */
-       if ((Control & ~FRAME_POLL_FINAL) == RFCOMM_Frame_UIH)
-         ResponsePacket.FCS = RFCOMM_GetFCSValue(&ResponsePacket, sizeof(ResponsePacket.FrameHeader));
-       else
-         ResponsePacket.FCS = RFCOMM_GetFCSValue(&ResponsePacket, sizeof(ResponsePacket.FrameHeader) + sizeof(ResponsePacket.Size));
+       ResponsePacket.FCS = RFCOMM_GetFCSValue(&ResponsePacket, CRCLength);
 
        /* Send the completed response packet to the sender */
        Bluetooth_SendPacket(&ResponsePacket, sizeof(ResponsePacket), Channel);
 }
 
-static uint8_t RFCOMM_GetFCSValue(const void* FrameStart, uint16_t Length)
+static uint8_t RFCOMM_GetFCSValue(const void* FrameStart, uint8_t Length)
 {
        const uint8_t* CurrPos = FrameStart;
        uint8_t        FCS     = 0xFF;
        
-       while (Length--)
-       {
-               FCS = pgm_read_byte(&CRC8_Table[FCS ^ *CurrPos]);
-               CurrPos++;
-       }
+       for (uint8_t i = 0; i < Length; i++)
+         FCS = pgm_read_byte(&CRC8_Table[FCS ^ *(CurrPos++)]);
 
-       return (0xFF - FCS);
+       return ~FCS;
 }
 
-static uint16_t RFCOMM_GetFrameDataLength(const uint8_t** BufferPos)
+static uint16_t RFCOMM_GetFrameDataLength(const uint8_t* const BufferPos)
 {
-       uint8_t FirstOctet  = *((*BufferPos)++);
+       uint8_t FirstOctet  = BufferPos[0];
        uint8_t SecondOctet = 0;
        
        if (!(FirstOctet & 0x01))
-         SecondOctet = *((*BufferPos)++);
+         SecondOctet = BufferPos[1];
        
-       return (((uint16_t)SecondOctet << 7) | (FirstOctet >> 1));
+       return (((uint16_t)SecondOctet << 7) | FirstOctet >> 1);
 }
 

diff --git a/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.h b/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.h
index d25b737..3f7887f 100644 (file)
--- a/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.h
+++ b/Demos/Host/Incomplete/BluetoothHost/Lib/RFCOMM.h
@@ -53,17 +53,31 @@
                #define RFCOMM_DEBUG_LEVEL                      2
                
                #define FRAME_POLL_FINAL                        (1 << 4)
+               
+               #define RFCOMM_CONTROL_DLCI                     0
        
        /* Enums: */
                /** Enum for the types of RFCOMM frames which can be exchanged on a Bluetooth channel. */
                enum RFCOMM_Frame_Types_t
                {
-                       RFCOMM_Frame_SABM  = 0x2F, /**< Set Asynchronous Balance Mode Field */
-                       RFCOMM_Frame_UA    = 0x63, /**< Unnumbered Acknowledgement Field */
                        RFCOMM_Frame_DM    = 0x0F, /**< Disconnected Mode Field */
                        RFCOMM_Frame_DISC  = 0x43, /**< Disconnect Field */
+                       RFCOMM_Frame_SABM  = 0x2F, /**< Set Asynchronous Balance Mode Field */
+                       RFCOMM_Frame_UA    = 0x63, /**< Unnumbered Acknowledgement Field */
                        RFCOMM_Frame_UIH   = 0xEF, /**< Unnumbered Information with Header check Field */
                };
+               
+               enum RFCOMM_Control_Commands_t
+               {
+                       RFCOMM_Control_Test                    = 0x20;
+                       RFCOMM_Control_FlowControlEnable       = 0xA0;
+                       RFCOMM_Control_FlowControlDisable      = 0x60;
+                       RFCOMM_Control_ModemStatus             = 0xE0;
+                       RFCOMM_Control_RemotePortNegotiation   = 0x90;
+                       RFCOMM_Control_RemoteLineStatus        = 0x50;
+                       RFCOMM_Control_DLCParameterNegotiation = 0x80;
+                       RFCOMM_Control_NonSupportedCommand     = 0x10;
+               }
        
        /* Type Defines: */
                typedef struct
@@ -84,16 +98,16 @@
                void RFCOMM_ProcessPacket(void* Data, Bluetooth_Channel_t* const Channel);
                
                #if defined(INCLUDE_FROM_RFCOMM_C)
-                       static void RFCOMM_ProcessSABM(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel);
-                       static void RFCOMM_ProcessUA(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel);
                        static void RFCOMM_ProcessDM(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel);
                        static void RFCOMM_ProcessDISC(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel);
+                       static void RFCOMM_ProcessSABM(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel);
+                       static void RFCOMM_ProcessUA(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel);
                        static void RFCOMM_ProcessUIH(const RFCOMM_Header_t* const FrameHeader, Bluetooth_Channel_t* const Channel);
 
                        static void RFCOMM_SendFrame(const uint8_t DLCI, const bool CommandResponse, const uint8_t Control,
                                                     const uint16_t DataLen, const uint8_t* Data, Bluetooth_Channel_t* const Channel);
-                       static uint8_t  RFCOMM_GetFCSValue(const void* FrameStart, uint16_t Length);
-                       static uint16_t RFCOMM_GetFrameDataLength(const uint8_t** BufferPos);
+                       static uint8_t  RFCOMM_GetFCSValue(const void* FrameStart, uint8_t Length);
+                       static uint16_t RFCOMM_GetFrameDataLength(const uint8_t* const BufferPos);
                #endif
                
 #endif