Tag Archives: seven segment led

Netduino Day 4 : Eight Digit Seven Segment LED Display with MAX7219

In Day 3 tutorial, we learnt basics of seven segment LED displays and discussed about a time-division multiplexing technique that reduces the number of required microcontroller I/O pins to drive multiple seven segment LED displays. Today we will move a step further and discuss about a serial interface (SPI) for driving 8 seven segment LED displays. The technique uses MAXIM’s MAX7219 LED driver chip that allows you to control 8 (or more in cascade configuration) common-cathode seven segment LED displays with only 3 I/O pins of Netduino. For illustrative purpose, we will use our 8-digit serial seven segment LED (8DSSSLED) display module here. The benefit of using MAX7219 is, it will do all the hard work of multiplexing operation and let the microcontroller do more important jobs. It supports SPI serial communication protocol.

Netduino controlling 8 Digit Serial Seven Segments LED using MAX7219

Read more

Lab 11: Multiplexing seven segment LED displays

In Lab 6, we discussed about interfacing a seven segment LED display to a PIC microcontroller. The seven segments were driven individually through separate I/O pins of the microcontroller. If we do just like that then for 4 seven segment LED displays, 28 I/O pins will be required, which is quite a bit of resources and is not affordable by mid-range PIC microcontrollers. That’s why a multiplexing technique is used for driving multiple seven segment displays. This tutorial shows how to multiplex 4 common anode type seven segment LED displays with a PIC16F628A microcontroller.

Multiplexing 4 common anode seven segment LED displays

Read more