Communications
Dynalite components communicate using DyNet. The physical layer consists of a modified RS-485 TIA/EIA-485-A serial bus running along CAT5 cable, blue and blue/white carry the hot and cold signal respectively, orange and orange/white carry +12 V DC, green and green/white carry 0 V, Brown and Brown/white are unused. End of line termination is required [1]
DyNet 1 is the most commonly used protocol over the bus, being messages of 8 bytes of data, the 8th byte being a checksum. Data is sent at speed of 9600 baud, 8 bits, no parity, 1 stopbit (8N1). Commonly there are two types of message sent via DyNet 1: logical and physical. Logical messages talk to Areas and Channels, and physical messages talk directly to the devices. These 2 are typically called 1C and 5C messages, on account of the first byte of their message.
A 1C message consist of: [1C] [Area] [Data 1] [OpCode] [Data 2] [Data 3] [Join] [Checksum]
Area is the Logical Area the message is to control.
OpCode defines the Action to be taken on the Area.
Join is a bitswitch which can be used to filter out selected channels.
An OpCode of 00 to 03 means the action is to send the given area into preset 1 to 4 plus 8 times the value of Data 3 over the time specified by Data 1 and Data 2.
An OpCode of 0A to 0D means the action is to send the given area into preset 5 to 8 plus 8 times the value of Data 3 over the time specified by Data 1 and Data 2.
That gives a possibility of 8 × 255 presets. A usual job uses 4 to 8, and generally preset 4 is reserved to 'Off' or 'all to 0%'.
DyNet 2 is used mainly to upload data to devices on the network. It allows larger messages of data to be sent at higher speeds (115200 baud), significantly reducing lag time.
