Creative macro definitions ??

[Torello]

Hello,

I've created some macro's inspired by the easy build in functions like Make8. The macro's do word and assembly very efficient !
However I'm wondering if I'm doing something 'tricky' or risky..

Any comments? How does CCS define their make8 ?

Regards,
Edwin.

//--- Macro definitions -------------------------------------------------------------------------------------
Typedef union { // This union typedef can be used for easy acces
int8 B[2]; // of bytes in integers
long int W;
} btwd;

#define Make8L(x) ((btwd)(x)).b[0] // return low-byte of word
#define Make8H(x) ((btwd)(x)).b[1] // return hi-byte of word
#define Or16H8(x,y) Make16(Make8H(x)|y, Make8L(x)); // Or-function hi-byte of word-x with byte-y
#define Or16L8(x,y) Make16(Make8H(x), Make8L(x)|y); // Or-function lo-byte of word-x with byte-y

[Ttelmah]

All good C.
Nice to see someone else using the define language constructively.
The only 'caveat', (doesn't apply to the examples given), is to be carefult to always 'bracket round' macros used inside macros, and be very wary about the defintion placements and order, since some odd results can otherwise apply.
The macro expansin, is carried out 'ahead' ofthe main compiler pass, so should always be safe, provided the code you generate with it is 'safe'.

Best Wishes

[Torello]

Thanks!
Can one also make/define their own #use definitons ? I want to connect the i/o- pins of my own driver module in the main module by using a #use directive. (would be very nice..)

[Ttelmah]

I would not do this. '#', is a reserved keyword in itself for the pre-processor, and has effects on so many things, that I _would_ be 'wary' of trying to do anything with this!.
However there is nothing potentially to stop you have a 'use_my_peripheral' setup function, with the macros.
Remember also, that the defines can be 'multi line'. Just put a '\' at the end of a line, and the definition will continue on the next line. Also if the define is bracketted, and the sections are seperated by commas, the value of the last statement is returned. So:

[Torello]

Thanks again ! Great tips! Shure going to use them.

Best wishes too,
Regards,
Edwin.

[tavioman]

[Torello]

Cool idea! Going to use it !

[tavioman]

I'm wondering if there is any procedure to make this more simple.
Like _TRACE_("");
No _TRACE1_ or _TRACE2_ .....etc.