Deep Blue C

The Deep Blue C (DBC) is one of the few C compilers for the Atari 8 bit. John H. Palevich is the author of this compiler. The syntax supported by DBC is close to the ANSI C with significant limitations.

Limitations

The following language constructs are not supported ^[1]:

 * structs
 * unions
 * multidimensional arrays
 * floating point numbers
 * sizeof operator
 * type casting 
 * functions return integer only results

Other non-standard properties of Deep Blue C:

 * The last part of "switch" clause must be ended with: "break", "continue" or "return".
 * char is unsigned.
 * The maximum length of source code line has to be less than 80 characters.
 * The number of arguments for functions cannot exceed 126.
 * $( and $) are used instead of { and }.

Sample program

The exemplary program writes the "Hello World!" message on the user screen ^[2].

 main()
 $(
   printf("Hello World!");
 $)

Performance

The DBC compiler does not create the native executable for 6502 processor but intermediate code called C-code. The C-code is then executed by C-code interpreter ^[1]. According to Atari 8-bit FAQ the DBC creates binary code for Intel 8080 processor and then executed by virtual 8080 machine ^[3]. It has some similarities to todays JAVA platform and it is also the main cause of low performance of DBC-created code.

References

1. ^ ^{a b} Deep Blue C documentation at Atari Archives [1]
2. ^ W. Zientara, "Jezyki programowania Atari cz.2", SOETO, Warsaw, 1989
3. ^ Atari 8-bit FAQ [2]