hi,,,

i read this definition but i need Know


@ device INTRC_OSC_NOCLKOUT
CMCON = 7 ' PortA = digital I/O
VRCON = 0 ' A/D Voltage reference disabled
' Set receive register to receiver enabled
DEFINE HSER_RCSTA 90h
' Set baud rate
DEFINE HSER_BAUD 2400

what is that mean(HSER)& (baud)??

and

some instruct assign to number like 90h & 2400??? what is the number mean?
is the number constant??if not what the other options??????



and thanx