// ******************************************************************************
//
// * Copyright:
//     (c) Mustangpeak Software 2013.
//
//     The contents of this file are subject to the GNU GPL v3 licence/ you maynot use
//     this file except in compliance with the License. You may obtain a copy of the
//     License at http://www.gnu.org/licenses/gpl.html
//
// * Revision History:
//     2011-01-28:   Created
//     2012-10-07:   Version 1.0
//
// * Description:
//    Defines global constants for NCE Bus Bridge
//
// ******************************************************************************
unit NMRAnetNceBridgeDefines;

uses
  NMRAnetDefines;

const
  NCEBUS_MAX_DATA_BYTE = 12;                                                    // Max number of databytes in a NCE message
  
  STATE_BUILD_INITIAL_CABS        = 0;
  STATE_DISCOVERDEVICES           = 1;
  STATE_DISCOVERNEXTDEVICE        = 2;
  STATE_SENDDEVICEINQUIRY         = 3;
  STATE_SENDDEVICESYNC            = 4;
  STATE_HANDLEMESSAGE             = 5;
  STATE_WAIT_FOR_NMRANET_REPLY    = 6;
  STATE_SEND_NMRANET_MESSAGE      = 7;
  STATE_SEND_INSTRUCTION_REPLY    = 8;
  STATE_DEVICEACKRESPONSE         = 9;
  STATE_TESTFORDISCOVERYMODE      = 10;
  STATE_ENUMERATEACTIVEDEVICES    = 11;
  STATE_WAITFORDEVICEMESSAGE      = 12;
  STATE_WAITFORACKRESPONSE        = 13;

  STATE_RS485_READ_CAB_BYTE_1   = 0;  // State machine states for the RS485 receiver
  STATE_RS485_READ_CAB_BYTE_2   = 1;
  STATE_RS485_FULL              = 2;

  ID_NO_DEVICE                         = $FE;
  ID_MIN_DEVICE                        = 2;
  ID_MAX_DEVICE                        = 63;   // 63 Devices on NceBus bus allowed not including ID = 0 or 1
  ID_PC_DEVICE                         = $FF;  // PC Device = $FF
  NCEBUS_PING                          = %10000000;   // P10A AAAA
  MAX_MISSED_PINGS_TO_REMOVE_FROM_BUS  = 12;          // not supported as NCE cabs can't be on the bus alone they need pings to other cabs to work.....bit 4/7/2013
  NCE_CAB_BUS_PADDING                  = 8;          // How many fixed Cab objects to always have on the bus to Ping, NCE Cabs can't be on the bus alone and a NCE CS has 8 always available.

  NCEBUS_BUS_HUNG_COUNT = 2;      // ~525ms counts and the bus is declared hung. (added 1 since we can't be sure when in the timer we started this covers if the timer interrupts right after we set the flag to 0) See: StartNceBusHungWatchdog for analysis of the max time of a device transaction
  REDISCOVERY_TIME         = 4;    // = Slow timer count (~525ms * REDISCOVERY_TIME = time to rescan for new Devices)
  NCEBUS_OLCB_BUS_TIMEOUT = 6;   // how long to count before giving up on a OLCB reply (~525ms steps)
  
  DS_NCEBUS_DEVICE_INACTIVE                            = $00;  // not Active, not Acknowledging
  DS_NCEBUS_DEVICE_ACTIVE                              = $01;  // Indicates the Device is active on the bus
  
  NCE_NO_SPEED_TO_REPORT    = %01111111;
  NCE_NO_KEY_TO_REPORT      = %01111101;
  NCE_SPEED_MASK            = %01111111;
  
  NCE_CAB_SELECT_LOCO       = $48;
  NCE_CAB_ENTER             = $40;
  
  NCE_CMD_CURSOR_ON         = $CF;
  NCE_CMD_CURSOR_OFF        = $CE;

type
  TNceBusDataArray = array[0..NCEBUS_MAX_DATA_BYTE-1] of Byte;
  PNceBusDataArray = ^TNceBusDataArray;

  TNceBusMessage = record
    Bytes: TNceBusDataArray;             // [RX, TX] The NceBus data that was recieved from Data Byte 1...Data Byte 15.  Does NOT include the Header Byte or the XOR Byte
    DataCount: Byte;                     // [RX, TX] Number of Valid Data Bytes
    MessageReadResult: Word;             // [RX] Error Message Result, see the E_SUCCESS, E_BUS_HUNG, E_WINDOW_TIMEOUT, etc constants
    CabID,                               // [TX] The CabID is the address of the Device to communicate with, sent with the 9th bit address UART protocol, Call Byte = 0 then it is not sent (for sending to the PC)
    StateMachineIndex,                   // [RX] The current state of the RX state machine that is run in UART RX interrupt
    StateMachineIndexDataByte: Byte;     // [RX] The current TNceBusDataArray index the RX state machine is operating on that is run in UART RX interrupt
  end;
  PNceBusMessage = ^TNceBusMessage;

 // Information about the Devices found on the NceBus bus
  TDevice = record
    State: Byte;                     // See XDS_NceBus_xxxxx Flags
    MissedPingCount: Byte;           // Number of times the Device did not respond to a ping, determine if it is taken off line
    Node: PNMRAnetNode;
  end;
  PDevice = ^TDevice;
  TDeviceList = array[ID_MIN_DEVICE..ID_MAX_DEVICE] of TDevice;  // Don't reserve a slot for device 0

  // Buffer to hold the data as it comes in on the RS485 bus
  TUARTReception = record
    NceBusData: TNceBusMessage;           // Syncronous message recieved from the command station pinging the NceBus bus begin dispatched
    Done: Boolean;                        // True when the reception is complete
  end;

  TNceBusBridgeInfo = record
    NceBusMessage: TNceBusMessage;   // This is the data from the Instruction that needs a reply before the OLCB message is sent and the data that needs to be sent back out the NceBus Bus after the OLCB replies
    RequiresReply: Boolean;                // The messages needs a replay from the OLCB
    ReplyRead: Boolean;                    // True when the NceBusMessage contains the information that needs to go out the NceBus bus
    WatchdogCount: Byte;                   // Counts (~525ms steps) before the Olcb reply is declared timed out, see NceBus_OLCB_BUS_TIMEOUT
    DataBuffer: TDataBuffer;                // NMRAnet message to send
    Datagram: TDatagramBuffer;             // NMRAnet datagram to send
  end;
  
type
  TNceBusStateMachineInfo = record
    DeviceList: TDeviceList;              // List of NceBus Devices (TDevice)
    iState: Short;                         // Current State the StateMachine is in
    Discovering: Boolean;                 // Discovering new Devices on the NceBus Bus
    iActiveDevice: Byte;                  // The Device currently being communicated with
    DiscoveryCount: Byte;                 // Counts (~525ms steps) between rediscovery intervals
    WatchdogCount: Byte;                  // Counts (~525ms steps) before the NceBus Bus is declared hung, see NceBus_BUS_HUNG_COUNT
    Bridge: TNceBusBridgeInfo;            // Info for messages that require querying information from the OLCB bus
    RS485: TUARTReception;                // Hold information about the UART reception on the NceBusBus
  end;
  PNceBusStateMachineInfo = ^TNceBusStateMachineInfo;
  
var
  NceBusStateMachineInfo: TNceBusStateMachineInfo;

implementation

end.