[MSX-C] Q&A official thread

 unsigned oldJiffy;
oldJiffy = Jiffy;
if ( Jiffy > (oldJiffy +10 ) ) {
update();
oldJiffy = Jiffy;
}

What's around that code? Where's the game loop?
And remember that Jiffy will eventually overflow from 0xffff to 0x0000. That may break the Jiffy > (oldJiffy +10) comparison.

1. How are Jiffy and oldJiffy declared?

2. Have you tried to step-by-step debug with OpenMSX Debugger?

3. Can you put

printf("Before If: Jiffy: %d; OldJiffy: %d", Jiffy, oldJiffy);

before the if and

printf("Before Update: Jiffy: %d; OldJiffy: %d", Jiffy, oldJiffy);

before update()?

You can try using a typedef;

void move(int* a, int* b) {}

typedef void (*f_type)(int*, int*);
f_type f_ptr = move;

Do you know the C standard version/name MSX-C is based on?

Isn't there a documentation that describes this C's syntax?

And why do you want to use this compiler instead of a modern one like SDCC or z88dk?
Do you program directly on MSX?

I started my project in Ascii C. I write is Visual Studio Code, save on a (DirAs) floppy, compile on openMSX. I've got about 900 lines of Ascii C code to migrate to SDCC. I've got no idea, how much problems I wil have when I migrate to SDCC. I expect a lot of code rewrite.

In MSX c, you've got one MSX library that has all MSX specific functions (mlib). More modern frameworks like MSXgl offer more functionality to go, but also consist of more seperate header files and different function names.

One advantage of Ascii C is that all MSX functions are in mlib (the msx library) so I don't have to include different header files. I just declare the functions I need. But the limitations of the compiler are gradually pushing me towards SDCC.