Interactivity via RS232
From SpinetiX Support Wiki
This page is about interactivity with external devices connected via the serial port.
Applies to HMP400/W (SYSTEMS), HMP350, HMP200, HMP130, and HMP100 devices.
Contents
Introduction
Interactivity via RS232 refers to the HMP quality of reacting in a user-defined manner (i.e. reactive action), following the input received from external devices via serial connection. This means that the HMP can interact with practically any RS-232 standard compliant device connected to its serial port, both to receive and send data messages. For instance, a message received on the serial port could trigger a content switch on the screen. Or the player could send a message on the serial port when a certain event occurs, like turning the screen on in the morning.
Here are some examples of third-party devices that can used:
- Control Systems: Crestron (e.g., MPC-M5-B-T), AMX, Extron
- Queue Management Systems: Qmatic
- GPS receivers: Navman, Evermore
- contact closure / relay controllers: NCD, Quasar, Neets QueBec
On the implementation side, the RS232 communication is handled through two distinct methods:
- JavaScript COM API;
- Serial port protocol file for an XML approach.
Configuration
To enable RS232 interactivity on the HMP, the first step is to make sure that the RS232 port is enabled on the HMP.
Next, if you intend using a protocol file, then you need to write that serial port protocol file and then activate it on the player.
How to create interactive content
Using JavaScript COM API
Currently, there's no interactive built-in widget included into Elementi Library for this type of interactivity, yet it should be fairly easy (though some JavaScript knowledge is required) to install a handler for com events as explained on the JavaScript COM API page.
Using a protocol file
Alternatively, an FSM protocol file can be written to translate RS232 input messages into Shared Variable update actions or into interactive events. With other words:
- Use the
<onInput>transition to match the command sent from the external device.- The matching is done using either the
dataormatchattribute. You can also change the state using thegotoattribute.
- The matching is done using either the
- Inside this transition or the specified state, use either the
<update>action (to update a Shared Variable) or the<fire>action (to fire an interactive event). - Use one of the interactive widgets from Elementi Library to implement a reactive action.
For such FSM files examples, see Receiving commands, Sending and receiving commands and NMEA-0183 protocol file. For a sample project, see GPS test project.