Sorry if this question is basic but I'm a bit stuck.
Trying to get 4 x 7 segment displays working using my arduino Uno and a MAX7219 chip. I believe I have wired everything up properly, based on this: Arduino Playground - HomePage and this Arduino Playground - HomePage.
In order to see if the displays are working I uploaded the Democode for the LedControl-library:
//We always have to include the library
#include "LedControl.h"/*
Now we need a LedControl to work with.
***** These pin numbers will probably not work with your hardware *****
pin 12 is connected to the DataIn
pin 11 is connected to the CLK
pin 10 is connected to LOAD
We have only a single MAX72XX.
*/
LedControl lc=LedControl(12,11,10,1);/* we always wait a bit between updates of the display */
unsigned long delaytime=250;void setup() {
/*
The MAX72XX is in power-saving mode on startup,
we have to do a wakeup call
/
lc.shutdown(0,false);
/ Set the brightness to a medium values /
lc.setIntensity(0,8);
/ and clear the display */
lc.clearDisplay(0);
}/*
This method will display the characters for the
word "Arduino" one after the other on digit 0.void writeArduinoOn7Segment() {
lc.setChar(0,0,'a',false);
delay(delaytime);
lc.setRow(0,0,0x05);
delay(delaytime);
lc.setChar(0,0,'d',false);
delay(delaytime);
lc.setRow(0,0,0x1c);
delay(delaytime);
lc.setRow(0,0,B00010000);
delay(delaytime);
lc.setRow(0,0,0x15);
delay(delaytime);
lc.setRow(0,0,0x1D);
delay(delaytime);
lc.clearDisplay(0);
delay(delaytime);
}
/
/
This method will scroll all the hexa-decimal
numbers and letters on the display. You will need at least
four 7-Segment digits. otherwise it won't really look that good.
*/
void scrollDigits() {
for(int i=0;i<13;i++) {
lc.setDigit(0,3,i,false);
lc.setDigit(0,2,i+1,false);
lc.setDigit(0,1,i+2,false);
lc.setDigit(0,0,i+3,false);
delay(delaytime);
}
lc.clearDisplay(0);
delay(delaytime);
}void loop() {
//writeArduinoOn7Segment();
scrollDigits();
}\
However. all that happens is that the decimal places light up and nothing else. Can anyone suggest what to do to work through and find out how to get them working. Eventually I want to use these as a counter that increments up 1 every time a switch is closed.
Many thanks, Ant