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TRANSLATING ASSEMBLY CODE FROM HC05 TO ST7

There are two ways to define a variable as public (which means visible from another module,

the C equivalent directive is “extern”). The first one is the one used in the above example (the

dot before the variable). The second one is to write the PUBLIC directive at the beginning of

the variable.asm file followed by the name of the variables you want to be public.

variable.inc: (file to include in all .asm source files)

TITLE “variable.inc”

EXTERN

var2.b

; the ad-

dress of var2 is a byte.

EXTERN

var3.w; the address of var3 is a word.

EXTERN

table.w; the address of table is a word.

In this .inc file, only the variables which have been defined as public in the corresponding .asm

file have to appear. That’s the reason why var1 doesn’t appear (it’s a local variable).

Instead of writing a “.b” or “.w” after the variable to specify that its address is a byte, you can

also write the BYTES or WORDS directives directly before the corresponding variables.

4.2 CONSTANTS

The best way to define all your constants is to declare them in a file (called constant.inc for ex-

ample) with the directive “#define constant_name value”. Constants defined in this way

don’t take any space in memory. All you have to do is include this .inc file in all your source

files (in all files where you use the constants):

constant.inc:

#define

const125

; const1 = 25 (decimal)

#define

const2 $1F

; const2 = 1F (hexadecimal)

#define

const3%11100001

; const3=11100001 (binary)

........

You can define as many constants as you want. Just make sure that the “#” symbol is always

the first character of the line but not in the first column.