Class MergMessage

  • All Implemented Interfaces:

    public class MergMessage
    extends GridConnectMessage
    Class for messages for a MERG CAN-RS hardware adapter.

    The MERG variant of the GridConnect protocol encodes messages as an ASCII string of up to 24 characters of the form: :ShhhhNd0d1d2d3d4d5d6d7; hhhh is the two byte (11 useful bits) header The S indicates a standard CAN frame :XhhhhhhhhNd0d1d2d3d4d5d6d7; The X indicates an extended CAN frame Strict Gridconnect protocol allows a variable number of header characters, e.g., a header value of 0x123 could be encoded as S123 rather than S0123 or X00000123. We choose a fixed number, either 4 or 8 bytes when sending GridConnectMessages to keep MERG CAN-RS/USB adapters happy. The 11 bit standard header is left justified in these 4 bytes. The 29 bit standard header is sent as <11 bit SID><0><1><0>< 18 bit EID> N or R indicates a normal or remote frame, in position 6 or 10 d0 - d7 are the (up to) 8 data bytes

    • Method Detail

      • setByte

        public void setByte​(int val,
                            int n)
        Set a byte as two ASCII hex digits

        Data bytes are encoded as two ASCII hex digits starting at byte 7 of the message.

        setByte in class GridConnectMessage
        val - the value to set, must be in range 0 - 255
        n - the index of the byte to be set