Link to the next address in the first two bytes, the line number in The program lines are stored as a linked list with the His first article gives some excellent diagrams and breakdowns of theīinary format.
Written a series of blog posts on masswerk.at that cover CommodoreīASIC V2 internal program and data representation in detail and giving However, later Commodore kernals "fix-up" the directory listing to move it to the start of BASIC for that machine.Īs discussed and linked in this thread, Norbert Landsteiner has LOAD "$",8), always use $0401 as the base, and this behavior dates back to the PET. Interestingly, the Commodore disk drives, which return a directory listing in the format of a BASIC program (i.e. On the VIC-20, the start of BASIC actually moves around, depending on expansion memory being installed. The VIC-20 and PET start at $0401 and the C128 starts at $1C01.
Technically, your BASIC program actually starts at $0801, as that is the location of the low-byte of the first pointer to the next line (line #2). The end of the BASIC program is indicated when the pointer to the next line equals $0000. Then starts the next line (#2) with a pointer to line #3. Then, comes the line number.įollowing this is the tokens that make up the actual BASIC code of the line, and terminated by a null ($00). Each line of the BASIC program is preceded by a pointer to the next line. The information you obtained elsewhere is incorrect.
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