diff --git a/main.c b/main.c
index 936bb8b..c7fecb3 100644
--- a/main.c
+++ b/main.c
@@ -40,8 +40,9 @@
 #include "print.h" // printing utilities
 #include "usart.h" // USART utilities
 #include "usb_cdcacm.h" // USB CDC ACM utilities
-#include "led_tm1637.h" // TM1637 7-segment controller utilities
 #include "rtc_ds1307.h" // DS1307 RTC utilities
+#include "led_tm1637.h" // TM1637 7-segment controller utilities
+#include "led_max7219.h" // MAX7219 7-segment controller utilities
 
 #define WATCHDOG_PERIOD 10000 /**< watchdog period in ms */
 
@@ -205,15 +206,17 @@ void main(void)
 		printf("current date: 20%02u-%02u-%02u %02u:%02u:%02u\n", rtc_ds1307_time[6], rtc_ds1307_time[5], rtc_ds1307_time[4], rtc_ds1307_time[2], rtc_ds1307_time[1], rtc_ds1307_time[0]);
 	}
 
-	// setup TM1637
-	puts("setup 7-segment display: ");
-	led_tm1637_setup();
-	if (!led_tm1637_time(88,88)) { // test display
+	// setup TM1637 and MAX7219 7-segments displays
+	puts("setup 7-segment displays: ");
+	led_tm1637_setup(); // setup TM1637
+	led_max7219_setup(); // setup MAX7219
+	if (!led_tm1637_time(88,88)) { // test TM1637 display
 		puts("could not send time to TM1637\n");
 	}
-	if (!led_tm1637_on()) { // switch on display
+	if (!led_tm1637_on()) { // switch on TM1637 display
 		puts("could not switch on TM1637\n");
 	}
+	led_max7219_test(true); // test MAX7219 display
 	for (uint32_t i=0; i<5000000; i++) { // wait a bit to have the user check the display
 		__asm__("nop");
 	}
@@ -223,8 +226,10 @@ void main(void)
 	if (!led_tm1637_off()) { // switch off display
 		puts("could not switch off TM1637\n");
 	}
+	led_max7219_test(false); // go back in normal operation
+	led_max7219_off(); // switch display off
 	puts("OK\n");
-	
+
 	// main loop
 	puts("command input: ready\n");
 	bool action = false; // if an action has been performed don't go to sleep