Datasheet
MikroElektronika
2
Serial 7-Seg Display 2 Additional Board
The Serial 7-Seg Display 2 additional board features eight 7-segment displays used to display digits. Connection between the
additional board and a development system is established via an IDC10 connector on the board and a 2x5 connector on one of the
developmet system’s ports. Communication between the additional board and a microcontroller is performed via a Serial Peripheral
Interface (SPI), whereas eight 7-segment displays on the additional board are used to display digits. When connecting the board to a
development system, it is necessary to set the appropriate switches on the DIP switch SW1 to the ON position.
In case EasyPIC, LV18F, EasyLV-18F, Easy24-33 and BigPIC development systems are used, the following switches on the DIP
switch SW1 should be set to the ON position:
Switch 1 - MOSI
Switch 4 - SCK
For EasyAVR and Easy8051 development systems, the following switches on the DIP switch SW1 should be set to the ON position:
Switch 3 - MOSI
Switch 6 - SCK
For the EASYdsPIC development system, the following switches on the DIP switch SW1 should be set to the ON position:
Switch 2 - MOSI
Switch 5 - SCK
Switches 7 and 8 on the DIP switch SW1 are used for connecting the CS pin (Chip Select) on the additional board to a development
system. CS lines may be connected to different I/O port pins. Accordingly, it is necessary to dene in the program, to be loaded into
the microcontroller, which pins will be used as the CS pin (Chip Select).
Figure 1: Serial 7-Seg Display 2 additional board
IDC10 connector used to
connect a development system
Displaying digits is enabled by the time-division multiplexing. All the operations related to multiplexing and displaying digits are
performed by using the MAX7219 circuit provided on the additional board. The time-division multiplexing of a 7-segment display is
based on fast turning the display segments on/off in such a manner that one gets impression that all eight digits are active at the same
time. The MAX7219 circuit feeds digit segments with a signal via pins marked SEGxx, whereas pins marked DIGx are used to select
one of eight displays to show the appropriate number.