What’s new?

• Full channel diapason (141 channels) is available for more flexible settings.

• Before this update, Tag/Bracer has searching the HMD Radio Socket through all available radio channels. In this update, you can set the channel manually, which makes the connection momentary.

• Data transferring latency has reduced (relevant for a situation when the big amount of tags/bracers are connected to one radio socket)

• Bandwidth was improved

• Maximum size of the radio package was increased

• Crosstalk protection was added (two radio sockets working on the same channel can not receive each other packages)

• The connection procedure was improved

• The list of default channels was changed

Using a full diapason of radio channels

Now 141 radio channels from 2360-2500 MHz diapason are available. In many countries, part of these channels requires licensing (2360-2400 MHz, 2488-2500 MHz).

An index of the radio channel is used everywhere in the software (0 = 2360 MHz, 140 = 2500 MHz)

Now you can use the mask for radio channels on Tags and Bracers. This is a string which consists of 141 symbols (“0” or “1”), where “1” means that the channel is active for search and “0” that channel will be ignored. A name of the property is “Channels Mask”. If you will use “full mask” (put “1” in each position) a search may be too long. But if you will activate only one channel in the mask the device can connect in a hundred milliseconds.

You can not reset the channel 92, because it is needed for connection of device with an unknown mask.

“-1”RadioChannelvalue means that HMD Radio Socket tries to choose one of radio channels from the list:

• 42 = 2402 MHz

• 66 = 2426 MHz

• 92 = 2452 MHz

• 114 = 2474 MHz

• 120 = 2480 MHz

The mask for Tags and Bracers for default channel looks like:

The list is based on statistics and this image:

It is highly recommended not to install channels that are closer than 5 MHz to each other (look at the picture above)

E.g. “0 and 6” is good. “0 and 5” is bad.

Device properties

Basically, there are 4 kinds of Antilatency devices:

• Alt tracker

• USB socket (w/o radio)

• HMD Radio socket

• Wireless radio sockets (Bracer and Tag)

Alt tracker can be used with any of these devices. A HMD Radio socket can be used as a typical USB socket without radio. If it’s not needed, or can be used with radio enabled to establish connection to the Tags and/or Bracers. Currently up to 2 slave devices can be connected to 1 HMD Radio socket (2 Bracers or 2 Tags or 1 Bracer and 1 Tag). If you need to connect more slave devices, you can add an additional HMD Radio socket.

Antilatency devices properties

Any Antilatency device has a properties list. Some of these properties are read-only, for example, hardware serial number. Some can be overwritten by the user, for example, “Tag”. Currently you can’t add or remove any properties. There is the Device Network tab in the AntilatencyService application, that allows you to view and edit device properties.

HMD Radio socket initial setup

If you plan to use Tags or Bracers in your project, first of all you need to set up a HMD Radio socket:

1. Choose a radio channel that will be used by this socket by setting the “RadioChannel” property. The default value is -1 – in this case the socket will choose the first free radio channel. Also, you can set a specific channel in the range of 0 - 140, that will be used. To know how the channel id is mapped to a radio frequency, take a look at the table at the end of this document.

2. Set a connection limit by applying the corresponding value to the “ConnLimit” property. If you don’t need to use radio on this socket, set the value to 0. If you plan to use only 1 wireless device, set it to 1. If you plan to connect 2 wireless devices to this socket, set it to 2. You can keep this setting at 2 while using only one wireless device, but some of the radio traffic will be used looking for a 2nd device. In case of an unstable radio connection caused by the distance between the USB socket and the wireless socket, some obstacles between these sockets, or additional radio noise on this channel from other emitters. In this case, some packets from the wireless socket may be lost which will lead to tracking task being restarted on the Alt tracker that connected to the wireless socket.

3. Optional: set the “Tag” for the socket – a user device identifier, for example, “LeftHand”, “Pistol”, etc. Please, check the corresponding section about how to use the “Tag” property.

To apply these settings to a HMD Radio socket, you need to:

1. Connect the HMD Radio socket to your PC

2. Run the AntilatencyService application

3. Open Device Network tab

4. Apply the settings to the HMD Radio socket (check the AntilatencyService manual to see details)

HMD Radio socket LED signals

Working with wireless sockets

There are 2 properties that can be controlled by the user on Tags and Bracers:

• Master serial number (MasterSN) – you can define the HMD Radio socket serial number to allow the bracer or the tag to connect only to that socket.

• Tag – some user device identifier, for example, “LeftHand”, “Pistol”, etc. Please, check the corresponding section about how to use the “Tag” property.

Basically, wireless sockets try to connect to the nearest HMD Radio socket. This behavior is quite simple and good for local testing purposes or when you have only one active HMD Radio socket at a time. But if you plan to create a multi-user game, this characteristic can cause some initial user setup issues and so on. So, you can allow a wireless socket to connect only to a specific HMD Radio socket. There are 2 ways to apply this setting:

Using AntilatencyService app:

1. Run the AntilatencyService

2. Open Device Network tab

3. Connect the HMD Radio socket to your PC

4. Power up the wireless socket

5. Click on the HMD Radio socket node in the Device Network tab

6. Select the “sys/HardwareSerialNumber” property value and press Ctrl+C

7. Click on the wireless radio socket node in the Device Network tab (Alt Bracer or Alt Tag)

8. Select the “MasterSN” property value, press Ctrl+V, and click on the Set button

Using a wireless socket power button:

1. Power up the HMD Radio socket

2. Power up the wireless socket by the single-click power on button

3. Check that the wireless socket is connected to the HMD Radio socket (both device LEDs will be blinking smoothly with the same color)

4. Press and hold the power button on the wireless socket for about 5 seconds, after that the wireless socket will be restarted and save the HMD Radio socket’s hardware serial number in the “MasterSN” property.

To reset this property:

Power up the wireless socket and press the power button for 5 seconds, after that the wireless socket will be restarted and the “MasterSN” property will be erased. In this case you don’t need to connect this wireless socket to the HMD Radio socket.

Using the AntilatencyService:

1. Run the AntilatencyService app

2. Open Device Network tab

3. Connect the HMD Radio socket to your PC

4. Power up the wireless socket

5. Click on the wireless radio socket node in the Device Network tab

6. Clear the “MasterSN” property value (“Enter property…” will be shown)

7. Click on the Set button

Using the “Tag” property

The “Tag” property can be edited on any socket. It is quite useful if you plan to work with multiple trackers at one time: 2 or more Alt trackers connected to 2 or more USB Sockets, or Bracers, or Tags. In this case you may need some info about what a specific tracker is responsible for. For example, you plan to use 1 HMD Radio socket and 2 Bracers, one on the left hand, the other on the right hand. So, you can set the “Tag” property value for the first bracer as “LeftHand”, and the second as “RightHand”, and then setup your project to search for tracker nodes that connected to the socket with a specific “Tag” property. You can find exactly the same usage in our base Unity package scene “AltBracerSample”.

Wireless socket LED signals