The sketch now compiles and uploads, but I get this error still.
Thanks again./home/al5ki/Arduino/libraries/HCMAX7219/Examples/HCMODU0082_Serial_7_Segment_Module_Example1/HCMODU0082_Serial_7_Segment_Module_Example1.ino: In function 'void loop()':
/home/al5ki/Arduino/libraries/HCMAX7219/Examples/HCMODU0082_Serial_7_Segment_Module_Example1/HCMODU0082_Serial_7_Segment_Module_Example1.ino:66:35: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings]
HCMAX7219.print7Seg("HELLO !!",8);
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