ACAB Setup Instructions

The goal of this page is to gather all information needed to set up an ACAB installation from the ground up.

The currently used hardware can be found at https://github.com/schneider42/moodlamp-rf

The board and schematic used for the ACAB installations are board/buslamp.{brd,sch} and are designed with EAGLE.

The hardware uses RS484 to signal data to the lamps and a 24 V to 28 V supply voltage. Both the RS484 signal and the supply voltage are carried on a single cable. To keep the cost down standard Cat 5 network cables are used.

To communicate with the host computer, the RS484 interface has to be adapted to another interface. The device described by board/ub.{brd,sch}. It is intended to be used with our IPv6 home automation project, but can also be used to act as an USB to RS485 bridge.

With standard 2 m long Cat. 5 cables, up to 8 lamps can be put into series. With more lamps or longer cables, the power loss in the cables is to large and the system starts to get unreliable. With shorter cables (e.g. 0.5 m), it should be possible to put more lamps into series.

For best utilization and robustness, power should not be injected from one side of a string. It should rather be injected from the middle of a string. This technique cancels out the voltage drops on the ground line (which helps the RS485 bus to stay in its operational limits) and gives better utilization of a single power supply.

Power can be injected by using the same circuit boards as the lamps. Only the two jacks, the jumper and the two screw terminals need to be populated. The board can now be used to inject power into the system. When using multiple power supplies in a single line, the jumper, bridging the 24 V power supply from one jack to the other, needs to be removed to decouple the power supplies.

RS485 Bridge <-> Lamp 1 <-> ... <-> Lamp 8 <--   --> Lamp 9 <-> ... <-> Lamp 16 <-|-> Lamp 17 <-> ... <-> Lamp 24 <--   --> Lamp 25 <-> ... <-> Lamp 32
                                              \ /                                 |                                  \ /
                                               |                                  |                                   |
                                       24 V Power Supply                 24 V Supply Wires Cut                24 V Power Supply

Each installation poses its own difficulties and tasks. The following general rules should give some guidance:

1. Test all parts of the system before going to an installation
2. It takes longer to set up the installation as expected.
3. During the installation, start testing parts of it as early as possible. Ideally you prepare some test animations to test single parts of the installation, while it gets built up. These tests should at least test each channel individually per lamp. The system must also still be reliable with all channels of all lamps turned on at the same time.
4. Think about people (unintentionally) running into your installation. Will they get hurt? Will your installation survive?

When using translucent plastic boxes from IKEA the following special steps apply:

The software for the RS485 bridge can be found inside the rs485bridge/ directory. It translates frames from a normal serial connection to
the RS485 bus used by the system. When used with the device mentioned above, it can be used to connect an ACAB installation to a PC.

To program the RS485 bridge:

cd rs485bridge
make
make fuse
make program

The bootloader for the boards can be found at https://github.com/schneider42/moodlamp-rf inside the ubloader/ directory.

The bootloader is used to update the firmware of the lamps while they are inside an installation and therefore inaccessible.
It consists of a small bootloader program, running on the lamps, and a set of Python and bash scripts to upload new firmware to the lamps.

The bootloader can upload new firmware to a lamp and program arbitrary parts of the EEPROM. To single out a lamp on the bus and only program a single one,
the bootloader can be used to compare an arbitrary section of the EEPROM to data transmitted via the bus.

The scripts use this feature to select a single lamp after all lamps performed a power on reset.

To flash lamps which have not yet a unique EEPROM content, the bootloader can be forced to consider the lamp selected.

./select-m644p [<ID>]

Starts to send the select command to the bus. If a lamp with a bootloader reboots and has the corresponding id programmed,
it will get selected. If no id is supplied any lamp on the bus will get selected. After a lamp got selected, the scripts returns.
If a lamp got selected, it turns green. If a lamp is not selected it stays red.

./set-m644p <ADDRESS>

Sets the address of a lamp to <ADDRESS>. <ADDRESS> must be a hexadecimal number greater 0x10. Addresses smaller than 0x10 are used for
multicast addressing. Example: set-m644p 5B

./flash-m644p <BINARY>

Loads the binary at <BINARY> directory and sends it to the lamp.

./boot-m644p

Starts the program inside the selected lamp. This command always return with a timeout.

Flash the bootloader to the lamp:

cd ubloader
make
make fuse
make program

Compile the moodlamp firmware:

cd moodlamp-bus
make

Connect the RS485 bridge with the lamp and apply 24V power to the lamp. The lamp starts to light up red.

cd ubloader
./select-m644p
./set-m644p <ADDRESS>   #use a different address for each lamp!
./flash-m644p ../moodlamp-bus/fnordlicht.bin
./boot-m644p

Compile the moodlamp firmware:

cd moodlamp-bus
make

Start to select any lamp:

cd ubloader
./select-m644p

Connect the RS485 bridge to the lamp and apply 24V power to the lamp. The lamp turns green.

./flash-m644p ../moodlamp-bus/fnordlicht.bin
./boot-m644p

The lamps should now boot the new firmware.

Compile the moodlamp firmware:

cd moodlamp-bus
make

Start to select the specific lamp

cd ubloader
./select-m644p <ADDRESS>  #Example: ./select-m644p "\x5A"

Toggle the power of all lamps, The specified lamp turns green and the script returns.

Flash the new firmare:

./flash-m644p ../moodlamp-bus/fnordlicht.bin
./boot-m644p

The ACAB daemon receives a stream of animation data via UDP and forwards it to the ACAB installation. It can control multiple RS485 bridges, connected to multiple sets of ACAB lamps.

The daemon can be found at https://github.com/muccc/acab-streetlife

It is located inside the server/ directory. There are two submodules: The acabslserver and the acabslrouter.

TODO: explain the UDP packet format

The acabslrouter accepts a stream of animation data and forwards the data to an acabslserver instance which controls a particular part of the installation. This makes it possible
to control an installation with more than one wall of lamps. The acabslrouter also supports different priorities and timeouts for different streams. This can be used to display an idle animation when
no other animation is active or overlay an active animation with some interactive game.

The server accepts a stream of animation data via UDP. If the stream modifies the state of a pixel which is controlled by the acabslserver, the server will translate the command to a command used by the lamps and will pass it to the appropriate RS484 bridge, associated with this pixel.