Keep the trace of this tutorial so that you can make your own device's
homepage (Java applet and a HTML page which contains the applet) or dedicated
Java application on the fly.
This section shows a detailed procedure of building an applet (or application) from launching
HelloDevice IDE to finally making a custom applet (or application).
HD1200 has a dual port RAM on which any connected device can read and write by provided external interface. It is able to work as a web server so that you can access the DPRAM by dedicated TCP/IP commands of an embedded Java applet. You can access the device without Java applet by the dedicated Java application that will be the final product of this sample also.
Launch HelloDevice IDE
Put Label in the design panel
Double click this component to popup its property editor.
Change its property values as following.
Now, the Label looks
Put RotaryGauge2 components in the design panel.
Modify component's property so that these components can display
HD1200's dual port RAM status properly.
Set "Value Expression" as "m2" so that this component can display
the value in the address m2 of DPRAM (3rd byte).
Note : When HelloDevice 1200 is not connected with any external devices, some addresses of DPRAM may change its value by itself and it's not a defect.
Change the properties of this component as in the following table with the order and resize components'
size by holding components' edge point.
property change order : MinorTickSpacing -> MajorTickSpacing -> MaxValue
-> MinValue.
(this order is given because each properties' values are relatively restricted.)
Now, the gauge looks
Put a VerticalSliderSwitch in the design panel. This switch will control the
address where previous RotaryGauge2 will monitor by setting its "Write
Destination" and "Value Expression" as "m2".
Change following properties to be same with previous RotaryGauge2.
Now, the switch looks
Note : The values read from dual port RAM is a byte value. So, keep it mind that the values over 127 or below -128 will automatically wrap around. If you want to change the displaying value (ex. real value to over 127 or below -128) or writing value (value over 127 or below -128 to real value), change the property "Value expression" or "Write expression".