DALI
| DALI | |
|---|---|
| Status | Stable
|
| menuconfig | Protocols->DALI light control |
| Pinning | no |
| Ecmd | yes |
| Depends on | ECMD (optional) |
| Requires | - |
| Code | https://github.com/ethersex/ethersex/tree/master/protocols/dali |
DALI light control provides the software layer to control DALI enabled digital ballast and transformers. DALI is an abbreviation for Digital Addressable Lighting Interface
DALI bus physical layer
- one master (Ethersex) and up to 64 lights (targets) on one bus
- 2 wire, no complex topology restrictions, no termination
- targets may only answer on master's request
- bus is isolated, but not SELV -> should be galvanic isolated on master's side
- 1200 baud, manchester-encoding
- 22.5VDC to 9.5VDC (16VDC nominally) is high level
- 6.5VDC to -6.5VDV (0VDC nominally) is low level
- bus is powered and held to high level by master
- targets (slaves) short the bus to transmit a low value
- master has to limit the current to 250mA
ECMD commands
| Command Syntax | Short description |
| dali raw <byte1> <byte2> | Sends a raw frame with 2 hex bytes. If you know what you are doing... |
| dali dim <target> <level> | Dims the specified target to the specified dim-level (0-254) |
| dali cmd <target> <command> [!] [?] | Sends a command (decimal) to the target. For a list of commands see the NXP application note or the DALI standard. To automatically repeat the command add a ! to the end of the command (necessary with some commands). A ? at the end means that command waits for an answer from the target. This answer is being returned as a decimal value. Not all commands will send an answer. |
| dali scmd <command> [!] [?] | Sends a special command to all connected targets (decimal 256-287). For a list of commands see the NXP application note or the DALI standard. A ? at the end means that command waits for an answer from the target. This answer is being returned as a decimal value. Not all commands will send an answer. |
Values for the <target> parameter:
| Targetcode | Description |
| all | All / Broadcast |
| snn | short address 0-63 (decimal) |
| gnn | group address 0-16 (decimal) |
Examples
| Example | ECMD |
| Dim all targets to 100% | dali dim all 254
|
| Target 12 off | dali dim s12 0
|
| Targets in group 3 to 50% | dali dim g3 127
|
| Set dim-speed on all targets to approx. 5.6 seconds (t=1/2*SQRT(2^x), x=1-15) | dali scmd 257 7
|
| Get actual dim value from target 4 | dali cmd s4 160 ? Reply: 180
|
| Is a target with short address 8 existing? | dali cmd s8 145 ? Reply: 255 (means true)
|
| Malfunction at target 8? | dali cmd s8 146 ? Reply: READ TIMEOUT (No answer means no malfunction)
|
| Program the single connected target the short address 3 | dali scmd 257 3
|
External sources
- DALI at Wikipedia german article (more complete)
- Freescale DRM004 Application Note good example for the hardware parts needed
- NXP AN10760 good commandlist and explanation of the data transfer
- NEMA Standard 243 bei Archenergy
If you are lucky, you can find the official DALI standard document IEC 60929 on google.
