All commands must start with a special command introducer (written as \i in iLCD Manager XE), which has the value 0xAA, and the command characters followed by the data block. This allows the controller to resynchronize in case of data errors or hang-ups of the controlling application. If the data block contains a 0xAA character (e.g. a word value of decimal 170), it must be quoted by a preceding 0xAA character.
Mind this behavior when sending commands from any controlling application. In iLCD Manager XE's editor, quoting is done automatically and therefore can be omitted. Note that inserting 0xAA characters manually in this case leads to syntax errors.
All commands respond with an [ACK] (0x06) character after they have been processed. If the command is unknown or contains an invalid value, a [NACK] (0x15) is returned as soon as the invalid value is recognized and the controller returns to "sync mode", which means it waits for a new command introducer (\i). In this case, the source of the problem is saved as an error code and can be accessed via the command Get Last Error Code. A complete list can be found in the section Error Codes. If an unexpected command introducer is found, processing of the current command is cancelled, and the next character is tried to be interpreted as a command. Any characters after a successful interpreted command, which are not a command introducer, are simply ignored.
Special considerations regarding input buffer size have to be taken into account when communicating via serial port (see Controlling the iLCD via Serial Port).
Find sections describing the possible parameter types in this chapter:
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