Three-color Modbus display

The SMI2-M is a universally applicable display for monitoring industrial processes. It operates via the RS-485 interface, and the displayed measurement values can be up to four digits. Imagine being able to streamline multiple devices without the usual technical issues.

Main features of the SMI2-M

• Three-color seven-segment display (green-red-yellow)
• RS-485 interface with galvanic isolation from the power supply.
• Supports Modbus RTU/ASCII protocols in Master/Slave/Spy mode.
• Programming via micro USB.
• Displays values such as INT, DINT, WORD, DWORD, REAL, STRING, Portrait, Time.
• Standardized design fitting into a standard 22.5 mm bore for signal lamps.

How the SMI2-M works:

• Configurable byte/register sequence for all operating modes.
• Display of values such as INT, DINT, WORD, DWORD, REAL, STRING, portrait (bit mask of the display segments), time (value in the format "xx:yy").
• Customizable number of leading zeros and decimal places.
• Supports blinking and ticker modes.
• Possibility of linear scaling of the obtained value.
• Control of color, blinking and other parameters via Modbus registers.
• Presence of a built-in logic mode to change the color and blinking mode for values outside the specified range.
• Control of LED brightness.
• Supports Modbus RTU/ASCII protocols in master/slave/spy mode.

Master - the display device acts as a master device that queries another device and displays the value of one of its parameters. This enables the display of data from a device that can only operate in slave mode, such as TRM. The indicator's color change and flashing are controlled by the indicator's built-in logic, as set by the user.

Slave - the indicator displays a value received from the master device (e.g. PLC or PR). The color change and flashing of the indicator can be controlled either by a command from the master device (according to its program) or by the built-in logic of the SMI2-M. Several indicators can be connected to one RS-485 bus.

Spy mode allows the indicator to connect to the bus where a master device is already present and "listen" to the data traffic and wait for requests or responses with specific parameters (device address, function code, register address). This allows the device to be used in existing systems in which it is not possible to reconfigure the devices. Another use case for this mode is synchronous data updating on multiple indicators using a broadcast from the master device to address 0. Each indicator is assigned an individual register number in the listened request so that each device can extract its own data from the transmitted request.