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Many decimal numeric indicators used in real airplanes can be replicated in your home cockpit using 7-segment LED modules, which can be a pretty realistic substitute, especially if you can find indicators with right size and color.

In SimVimCockpit you can choose what type of control is most suitable for every of your 7-segment indicators, any display can be made using:

  • 8-bit shift registers (74HC595 and similar)
  • 16-bit LED drivers (DM13A and similar)
  • LED display driver MAX7219
  • LED display driver TM1637
  • SimVimCockpit© firmware control all of these display types directly, all program code has been developed from scratch, without using any libraries.

You can assemble displays yourself (how to make any 7-segment display), with any number and size of digits, using the DM13A LED drivers, 74HC595 registers, or MAX7219 driver.

Also, there are various pre-assembled modules on the market, with MAX7219 or TM1637 drivers, or modules with 74HC595 registers - you just need to connect display module to one of the 16 output and configure what to display on it and how.


All 7-segment displays are connected to one CD74HC4067 multiplexer board that is used as output extension for 16 devices. So, you can have in total up to 16 different 7-segment displays that are numbered in the range of 1 to 16.

    Each connected display can consist of up to 8 digits and be used to output 2 or 3 parameters simultaneously when one parameter value is shifted relative to the other.
The extension board for 7-segment displays is connected to the same common address bus that is used in your system for all other multiplexers - pins #22,23,24,25 are used as address lines. The "SIG" (signal) input is connected to "SD" output (pin #26) of Arduino.

Each display module has 3 input signal lines (besides power lines). You need to connect the "CLK" input to the extended otput assigned for this 7-segment display.

Two other signal inputs - "D" and "L" - should be connected to the corresponding common lines - "D" (pin #28) and "L" (pin #30) output signals. Read more information about 7-segment displays on the tech guide pages

Note:      The "L" and "D" signals are not used for TM1637 driver, that is controlled using additional fixed output pin #29 marked as "T" and connected to "DIO" input of all TM1637 used.

Single Display connection

If you have only one 7-segment display in your cockpit (wich also can be used to display 2 or 3 parameters) , you have the option of connecting it without an extension board. Just connect the "CLK (S)" signal of your display directly to the "SD" output (pin #26).

You can also use this "single-display" connection if you want to test output to 7-segment display in SimVimCockpit before you have a multiplexer board.


The configuration is unified for all displays, you'll only need to select display type and some additional options. All listed parameters are pre-configured for output in the right format, with dot position, number of digits and some of the display options pre-defined.


Any display can be easily configured to output more than one data value. For example, you can have 2 or 3 independent data on one 8-digit display. In the picture above you can see Bus Voltage + Bus Load on the right TM1637 display and DME distance + DME time on the upper MAX7219 display).

To output additional data on the same display, you need to select second parameter, then select the same display number as for the first parameter was assigned, and enter shift position number.

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