Chapter 6: C Functions and Program Structures

nctions, which use extra RAM. Also macros create in-line code that can be

rocessor overhead). And finally, macros don’t

es:

double da = 12;

double db = 14;

tion, the parameters require a data type such as int or double,

there is casting, but that’s another topic).

on

amilies that differ only in a few features, pinouts,

ons. You can write C code for the entire family if

hings that differ. Let’s say that SuprMic16 uses pins

ansmit and receive, while SuprMic8 uses pins 6 and 14,

and 2. We put the following in our SuprMic.h file:

define RXD 13

cX == 8

TXD 6

# define RXD 14

uprMicX = 4

or SuprMicX TXD and RXD pins."

rMic8 in our Killer Cylon Robot project we should put the

fu
faster than function calls (no p
require formally declared data typ

double dc = 7;
double dd = 0;

dd = larger( (db-da), dc);

If larger() was a func
but couldn’t use both (okay,

Conditional Inclusi

Often microcontrollers come in f
memory size, and register locati
you substitute alias for the t
12 and 13 for USART tr
and SuprMic4 uses pins 1

#if SuprMicX == 16

define TXD 12

#elif SuprMi

define

#elif S

define TXD 1

define RXD 2

#else

error “No definition f

#endif

If we are using the Sup
following in our CylonKillerRobot.h file:

#ifndef SuprMicX

# define SuprMicX = 8

# include <SuprMic.h>