Arduino Mqtt

Sketch to receive commands from an mqtt broker. The different commands are coded by defined bytes in the payload of the mqtt message. The skeatch uses the pubsub library.

Init Panel

Initializes the “panel” If the provided frame number is smaller than the curent frame number, the operation will be canceled. If the memory for the leds already has been allocated, the operation will be canceled. If the first byte ist not CMD_SHOW, the operation will be canceled.

Byte Position

Index	Description
0	Command Byte. must be CMD_SHOW
1	width of the panel. The number of leds per row.
2	height of the panel. The number of rows.
3	HIGH byte of the initial frame nr. .
4	LOW byte of the initial frame nr.

param cmdbuffer:  Pointer the the byte buffer with the command bytes. type cmdbuffer:byte*

void initPanel(byte* cmdbuffer, uint16_t length)

Show Panel

Updates the LEDs.

If the provided frame number is smaller than the curent frame number, the operation will be canceled. If length is not 3, operation will be canceled.

Byte Position

Index	Description
0	Command Byte. must be CMD_SHOW
1	HIGH byte frame nr to be updated.
2	LOW byte frame nr to be updated.

void showPanel(byte* cmdbuffer, uint16_t length)