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4. Info File Format

The info file contains lists of specifications grouped together. Each group directive has an identifying token and an attribute list enclosed in curly braces. Attributes have a name followed by a value. The syntax of the value depends on the type of the attribute. String attributes are places in double quotes, numeric attributes may be specified as decimal numbers or hexadecimal with a leading dollar sign. There are also attributes where the attribute value is a keyword, in this case the keyword is given as is (without quotes or anything). Each attribute is terminated by a semicolon.

        group-name { attribute1 attribute-value; attribute2 attribute-value; }

4.1 Comments

Comments start with a hash mark (#) and extend from the position of the mark to the end of the current line. Hash marks inside of strings will of course not start a comment.

4.2 Specifying global options

Global options may be specified in a group with the name GLOBAL. The following attributes are recognized:

COMMENTS

This attribute may be used instead of the --comments option on the command line. It takes a numerical parameter between 0 and 4. Higher values increase the amount of information written to the output file in form of comments.

CPU

This attribute may be used instead of the --cpu option on the command line. It takes a string parameter.

INPUTNAME

The attribute is followed by a string value, which gives the name of the input file to read. If it is present, the disassembler does not accept an input file name on the command line.

INPUTOFFS

The attribute is followed by a numerical value that gives an offset into the input file which is skipped before reading data. The attribute may be used to skip headers or unwanted code sections in the input file.

INPUTSIZE

INPUTSIZE is followed by a numerical value that gives the amount of data to read from the input file. Data beyond INPUTOFFS + INPUTSIZE is ignored.

OUTPUTNAME

The attribute is followed by string value, which gives the name of the output file to write. If it is present, specification of an output file on the command line using the -o option is not allowed.

The default is to use stdout for output, so without this attribute or the corresponding command line option -o the output will go to the terminal.

PAGELENGTH

This attribute may be used instead of the --pagelength option on the command line. It takes a numerical parameter. Using zero as page length (which is the default) means that no pages are generated.

STARTADDR

This attribute may be used instead of the --start-addr option on the command line. It takes a numerical parameter. The default for the start address is $10000 minus the size of the input file (this assumes that the input file is a ROM that contains the reset and irq vectors).

4.3 Specifying Ranges

The RANGE directive is used to give information about address ranges. The following attributes are recognized:

END

This gives the end address of the range. The end address is inclusive, that means, it is part of the range. Of course, it may not be smaller than the start address.

NAME

This is a convenience attribute. It takes a string argument and will cause the disassembler to define a label for the start of the range with the given name. So a separate LABEL directive is not needed.

START

This gives the start address of the range.

TYPE

This attribute specifies the type of data within the range. The attribute value is one of the following keywords:

ADDRTABLE

The range consists of data and is disassembled as a table of words (16 bit values). The difference to the WORDTABLE type is that a label is defined for each entry in the table.

BYTETABLE

The range consists of data and is disassembled as a byte table.

CODE

The range consists of code.

DBYTETABLE

The range consists of data and is disassembled as a table of dbytes (double byte values, 16 bit values with the low byte containing the most significant byte of the 16 bit value).

DWORDTABLE

The range consists of data and is disassembled as a table of double words (32 bit values).

RTSTABLE

The range consists of data and is disassembled as a table of words (16 bit values). The values are interpreted as words that are pushed onto the stack and jump to it via RTS. This means that they contain address-1 of a function, for which a label will get defined by the disassembler.

SKIP

The range is simply ignored when generating the output file. Please note that this means that reassembling the output file will not generate the original file, not only because the missing piece in between, but also because the following code will be located on wrong addresses. Output generated with SKIP ranges will need manual rework.

TEXTTABLE

The range consists of readable text.

WORDTABLE

The range consists of data and is disassembled as a table of words (16 bit values).

4.4 Specifying Labels

The LABEL directive is used to give names for labels in the disassembled code. The following attributes are recognized:

ADDR

Followed by a numerical value. Specifies the value of the label.

NAME

The attribute is followed by a string value which gives the name of the label.

SIZE

This attribute is optional and may be used to specifiy the size of the data that follows. If a size greater than 1 is specified, the disassembler will create labels in the form label+offs for all bytes within the given range, where label is the label name given with the NAME attribute, and offs is the offset within the data.

4.5 An Info File Example

The following is a short example for an info file that contains most of the directives explained above:

        # This is a comment. It extends to the end of the line
        GLOBAL {
            OUTPUTNAME      "kernal.s";
            INPUTNAME       "kernal.bin";
            STARTADDR       $E000;
            PAGELENGTH      0;                  # No paging
            CPU             "6502";
        };


        RANGE { START $E612;    END   $E631; TYPE Code;      };
        RANGE { START $E632;    END   $E640; TYPE ByteTable; };
        RANGE { START $EA51;    END   $EA84; TYPE RtsTable;  };
        RANGE { START $EC6C;    END   $ECAB; TYPE RtsTable;  };
        RANGE { START $ED08;    END   $ED11; TYPE AddrTable; };

        # Zero page variables
        LABEL { NAME "fnadr";   ADDR  $90;   SIZE 3;    };
        LABEL { NAME "sal";     ADDR  $93;   };
        LABEL { NAME "sah";     ADDR  $94;   };
        LABEL { NAME "sas";     ADDR  $95;   };

        # Stack
        LABEL { NAME "stack";   ADDR  $100;  SIZE 255;  };

        # Indirect vectors
        LABEL { NAME "cinv";    ADDR  $300;  SIZE 2;    };      # IRQ
        LABEL { NAME "cbinv";   ADDR  $302;  SIZE 2;    };      # BRK
        LABEL { NAME "nminv";   ADDR  $304;  SIZE 2;    };      # NMI

        # Jump table at end of kernal ROM
        LABEL { NAME "kscrorg"; ADDR  $FFED; };
        LABEL { NAME "kplot";   ADDR  $FFF0; };
        LABEL { NAME "kiobase"; ADDR  $FFF3; };
        LABEL { NAME "kgbye";   ADDR  $FFF6; };

        # Hardware vectors
        LABEL { NAME "hanmi";   ADDR  $FFFA; };
        LABEL { NAME "hares";   ADDR  $FFFC; };
        LABEL { NAME "hairq";   ADDR  $FFFE; };


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