: <STX><LEN><CMD><data_1>...<data_n><CHECKSUM><ETX> : two-complement of the sum of all previous bytes in the packet

Transcription

1 VM201 TCP protocol Generic TCP Protocol description Packet STX LEN CMD data_x CHECKSUM ETX : <STX><LEN><CMD><data_1>...<data_n><CHECKSUM><ETX> : 0x02 : number of bytes in packet incl. STX & CHECKSUM : command byte : optional data bytes : two-complement of the sum of all previous bytes in the packet : 0x03 At opening a connection and no authentication is needed there will be send: - logged in successfully: <STX><5><CMD_LOGGED_IN><CHECKSUM><ETX> At opening a connection and authentication is needed there will be send: - authentication needed: <STX><5><CMD_AUTH><CHECKSUM><ETX> The client will answer with username and password (max 8 characters): - username: <STX><14><CMD_USERNAME><char1 of username>...<char9 of username><checksum><etx> - password: <STX><14><CMD_PASSWORD><char1 of password>...<char9 of password><checksum><etx> If the username and password are invalid the following packets will be send: - access denied: <STX><5><CMD_ACCESS_DENIED><CHECKSUM><ETX> - session closed: <STX><5><CMD_CLOSED><CHECKSUM><ETX> - the client will be disconnected If the username and password are valid the following packets will be send:

2 - logged in successfully: <STX><5><CMD_LOGGED_IN><CHECKSUM><ETX> After successfully logged in the names (max 16 characters) of the 8 output channels and input will be send: - channel names: <STX><22><CMD_NAME><Channelnr><char1 name>...<char16 of name><checksum><etx> The status will be send: - output, timer & input status: <STX><8><CMD_STATUS><output status><output timer status><input status><checksum><etx> Output status bits = channels ; bit=0 OFF; bit=1 ON Output timer status bits = timer channels ; bit=0 DISABLED; bit=1 ENABLED Input status bit 0 = input channel; bit=0 OFF; bit=1 ON Now we are listening to the following commands from the client: - status request: <STX><5><CMD_STATUS_REQ><CHECKSUM><ETX> - switch an output channel ON: <STX><6><CMD_ON><channels><CHECKSUM><ETX> Channel bits = channels ; bit=0 no change ; bit=1 switch channel ON - switch an output channel OFF: <STX><6><CMD_OFF><channels><CHECKSUM><ETX> Channel bits = channels ; bit=0 no change ; bit=1 switch channel OFF - toggle an output channel: <STX><6><CMD_TOGGLE><channels><CHECKSUM><ETX> Channel bits = channels ; bit=0 no change ; bit=1 toggle channel - pulse an output channel: <STX><8><CMD_PULSE><channels><pulsetime><units><CHECKSUM><ETX>

3 Channel bits = channels ; bit=0 no change ; bit=1 pulse channel pulse time: units: 's'= seconds; 'm' = minutes; 'h' = hours - update all output channels: <STX><6><CMD_UPDATE><channels><CHECKSUM><ETX> Channel bits = channels ; bit=0 switch channel OFF; bit=1 switch channel ON - enable an output channel timer: <STX><6><CMD_TMR_ENA><channels><CHECKSUM><ETX> Channel bits = channels ; bit=0 no change ; bit=1 switch channel ON - disable an output channel timer: <STX><6><CMD_TMR_DIS><channels><CHECKSUM><ETX> Channel bits = channels ; bit=0 no change ; bit=1 switch channel OFF - toggle an output channel timer: <STX><6><CMD_TMR_TOGGLE><channels><CHECKSUM><ETX> Channel bits = channels ; bit=0 no change ; bit=1 toggle channel - connection closed: <STX><5><CMD_CLOSED><CHECKSUM><ETX> Every time the status changes it will be send an update to the client #define MIN_GENERIC_TCP_PACKET_SIZE 5 #define MAX_GENERIC_TCP_PACKET_SIZE 22 #define STX 0x02 #define ETX 0x03 #define CMD_AUTH 'A' // connected with authentication needed

4 #define LEN_CMD_AUTH 5 #define CMD_USERNAME 'U' // connected with authentication needed #define LEN_CMD_USERNAME 14 #define CMD_PASSWORD 'W' // connected with authentication needed #define LEN_CMD_PASSWORD 14 #define CMD_LOGGED_IN 'L' // successfully logged in #define LEN_CMD_LOGGED_IN 5 #define CMD_ACCESS_DENIED 'X' // access denied #define LEN_CMD_ACCESS_DENIED 5 #define CMD_CLOSED 'C' // connection closed #define LEN_CMD_CLOSED 5 #define CMD_NAME 'N' // channel name #define LEN_CMD_NAME 22 #define CMD_STATUS_REQ 'R' // status request #define LEN_CMD_STATUS_REQ 5 #define CMD_STATUS 'S' // output, timer & input channel status #define LEN_CMD_STATUS 8

5 #define CMD_ON 'O' // switch channel on #define LEN_CMD_ON 6 #define CMD_OFF 'F' // switch channel off #define LEN_CMD_OFF 6 #define CMD_TOGGLE 'T' // toggle channel #define LEN_CMD_TOGGLE 6 #define CMD_PULSE 'P' // pulse channel #define LEN_CMD_PULSE 8 #define CMD_UPDATE 'V' // update all channels #define LEN_CMD_UPDATE 6 #define CMD_TMR_ENA 'E' // enable timer channel programs #define LEN_CMD_TMR_ENA 6 #define CMD_TMR_DIS 'D' // disable timer channel programs #define LEN_CMD_TMR_DIS 6 #define CMD_TMR_TOGGLE 'G' // toggle timer channel programs #define LEN_CMD_TMR_TOGGLE 6

6 VM201_CMD_AUTH_REQUIRED VM201_CMD_USERNAME VM201_CMD_PASSWORD VM201_CMD_AUTH_OK VM201_CMD_AUTH_FAILED VM201_CMD_CLOSING VM201_CMD_CHANNEL_NAME VM201_CMD_STATUS_REQUEST VM201_CMD_STATUS VM201_CMD_SWITCH_ON VM201_CMD_SWITCH_OFF VM201_CMD_TOGGLE VM201_CMD_PULSE VM201_CMD_ENABLE_TIMER VM201_CMD_DISABLE_TIMER VM201_CMD_TOGGLE_TIMER VM201_CMD_FORCE_STATUS = $41; // 'A' = $55; // 'U' = $57; // 'W' = $4C; // 'L' = $58; // 'X' = $43; // 'C' = $4E; // 'N' = $52; // 'R' = $53; // 'S' = $4F; // 'O' = $46; // 'F' = $54; // 'T' = $50; // 'P' = $45; // 'E' = $44; // 'D' = $47; // 'G' = $56; // 'V' Checksum calculation in Delphi (pascal): Code: function VM201Checksum(Data: array of Byte; Size: Integer): Byte; var i: Integer; n: Byte; begin n := 0; for i:=0 to Size-1 do n := n + Data[i]; Result := (1 + (not ($FF and n))); end; The length is the length of the entire packet, every byte <STX><6><CMD_TOGGLE><channels><CHECKSUM><ETX> 1 <STX> 2 <6> 3 <CMD_TOGGLE> 4 <channels> 5 <CHECKSUM> 6 <ETX>

7 The checksum is calculated by adding every byte up to the checksum byte checksum = <STX> + <6> + <CMD_TOGGLE> + <channels> Inverting the bits checksum = not checksum And adding one checksum = checksum + 1