Intelligent Roadway Information System
View ➔ Maintenance ➔ Comm Links menu item
A controller is an end-point for a comm link. Each controller can have one or more associated devices, depending on the protocol. Sometimes a controller represents a separate physical box, which is connected to devices, and other times the controller may be embedded within the device. In either case, a controller is required for any communication to a device.
controller_io resource returns an array of objects consisting
resource_n of associated devices.
|Read Only||name, location, setup, fail_time||geo_loc|
|👉 Operate||download, device_req|
|💡 Plan||condition, notes|
|🔧 Configure||comm_link, drop_id, cabinet_style||password|
Some protocols support multi-drop addressing, while others are single-drop only. Multi-drop addressing allows multiple controllers to share the same comm link — typically for serial communication. Each controller must be assigned a unique (to the comm link) drop address, which is used to route all messages sent to the controller. For single-drop protocols, the drop address is ignored.
Authentication is supported or required by some communication protocols. The controller password field is used to enter authentication data.
- For NTCIP, this represents the SNMP community name. If no controller
password is set, the
Publiccommunity name will be used.
- Web-based devices may require HTTP Basic Authentication. For these types of
devices, the password field should contain both the user name and password,
separated by a colon (
- For CBW, the user name portion must be
none. HTTP Basic Authentication can be enabled on the setup page of the CBW device (setup.html).
- SierraGX modems can be configured to require authentiation. In this case, separate the username and password with a colon, in the same manner as HTTP basic authentication.
A device is one of several types of traffic control or sensing systems. These include:
- dynamic message signs — DMS
- gate arms
- lane-use control signs — LCS
- ramp meters
- road weather information systems
- tag readers
- vehicle detection systems
- video monitors
The controller must also be associated with a comm link which communicates using an appropriate protocol for the device.
Each controller has a set of IO pins for connecting devices or flow streams. Every device or flow stream must be assigned to an IO pin to be used. The function of these pins is protocol specific.
Controllers can have an associated cabinet style, used for MnDOT-170 and Natch protocols.
|🔧 Configure||police_panel_pin_1, police_panel_pin_2, watchdog_reset_pin_1, watchdog_reset_pin_2, dip|