How to test MAX7219 ?
I'm failing to drive a dual common collector 7 segment display [ Lite-ON LTD-5623BG] with a MAX7219 running example
LedControl.h / LCDemo7Segment .... example without success.
I've verified ;
pin 12 is connected to the DataIn
pin 11 is connected to the CLK
pin 10 is connected to LOAD
9 & 4 grounded
19 + 5V
10K between 18 & 19
paralleled segments A thru G [display(verified with +5V)] and tied to 7219 SEG(A>G) pins
cathodes to DIG0 and DIG1
I mixed up connections at first try and 7219 may be toast?
How easy is it to toast 7219?
how to send hex code OxXF for built in display test ?
where's best resource for learning lc.set ... tutorial ... documentation ?
SERIAL DATA how does DATA overlay with params
D15 D14 D13 D12 -|- D11 D1 D9 D8 -|- D7 D6 D5 D4 D3 D2 D1 D0
lc.setChar (addr,digit,value,dp); // don't quite get difference between setRow & setChar ?
lc.setRow (addr,digit,value,dp); // what is meant by digit position
// LedControl.h code follows
/*
- Display a hexadecimal digit on a 7-Segment Display
- Params:
- addr address of the display
- digit the position of the digit on the display (0..7)
- value the value to be displayed. (0x00..0x0F)
- dp sets the decimal point.
*/
void setDigit(int addr, int digit, byte value, boolean dp);
/*
- Display a character on a 7-Segment display.
- There are only a few characters that make sense here :
- '0','1','2','3','4','5','6','7','8','9','0',
- 'A','b','c','d','E','F','H','L','P',
- '.','-','_',' '
- Params:
- addr address of the display
- digit the position of the character on the display (0..7)
- value the character to be displayed.
- dp sets the decimal point.
*/
void setChar(int addr, int digit, char value, boolean dp);
// end chunk of LedControl.h
//most simple test sketch
#include "LedControl.h"
directives will be most appreciated ... don't have oscilloscope
/*
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);
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);
}
void loop() {
// lc.setChar(0,0,0xXF);
// delay(delaytime);
lc.setChar(0,0,'d',false);
delay(delaytime);
}