This page describes the use of the program 'decodify'.

I. SYNOPSIS

decodify -f config_file [-s] [-b|-o|-h] number_string

decodify is a simple string parsing program that takes a numerical string as a command line argument and prints out its various parts. The string is supposed to represent concatenated values of several variables. decodify prints out the value of these variables. The order of concatenation of the variables, from lower to higher order bits, as well as their names are specified in a configuration file. The name of this file is also specified as a command line argument.

Although it can be used in various cases, the main reason behind the creation of decodify is to extract the sub-parts of control bus in digital logic simulation. A control bus usually consists of a number of independent control signals and/or sub-busses. When displaying the values of the individual signals or sub-buses is possible, it is not desirable as it will clutter the screen or the logfile.

The full description of the command line arguments are:

-f config_file:
gives the location of the configuration file that decodify use for decoding. More on the format of the configuration file is given in Section II.

-s:
tells decodify that the configuration file is in 'MSB LSB' format rather than the 'Width' format. 'Width' is the default. More on this in Section II.

-b, -o, -h:
the base (binary, octal, hexadecimal (default)) decodify uses to for interpreting the numerical string.

number_string:
the string input.

II. CONFIGURATION FILE

The configuration (or, 'config') file specifies the names, the order and the widths of the variables whose concatenated value is represented by the input numerical string. It can be specified in one of the two formats.

The first format of the config file is given below:

FIELD NAME\tWIDTH

The second format is of the form:

FIELD NAME[\tMSB\tLSB]

The second format is valid only if '-s' command line option has been specified.

Tabs are used as delimeters for the fields.

'FIELD NAME' is the name of the field and may contain blank(s), but not tabs. A field name of 'Reserved' or 'reserved' are counted, but not printed.

'WIDTH' refers to the width of the variable.

'MSB' is the Most Significant bit of a bus. For a wire, no MSB is specified.

'LSB' is the Least Significant bit of a bus. For a wire, no LSB is specified. The value of LSB does not need to be smaller than the value of MSB.

III. EXAMPLES

In the following examples, '\t' is a tab character. All these examples can be found in the ./examples directory.

Example 1:

   % cat c1 
   first field\t3
   second Field\t1
   Third               Field    5

   % decodify -f c1 f53
   first field: 0x3. 
   second Field: 0x0. 
   Third               Field : 0x15. 

Example 2:

   % cat c2
   first field\t3
   reserved\t1
   Third               Field\t5

   % decodify -f c2 f53
   first field: 0x3. 
   Third               Field : 0x15. 

Example 3:

   % cat c3
   First Field\t3
   Second Field\t1
   Third Field\t4
   Fourth Field\t10

   %decodify -f c3 f53
   First Field: 0x3. 
   Second Field: 0x0. 
   Third Field : 0x5. 
   Fourth Field : 0xf. 

Example 4:

   % cat c4
   First Field  9       7
   Second Field
   Third Field  12      16

   % decodify -f c4 -s f53
   First Field: 0x3. 
   Second Field: 0x0. 
   Third Field : 0x15. 

Example 5:

   % decodify -f c4 -s -b 111101010011
   First Field: 0x3. 
   Second Field: 0x0. 
   Third Field : 0x15. 

IV. DOWNLOAD

Click here to get the latest gzipped-tar version of the release.

V. AUTHOR

decodify is designed, implemented and maintained by Swapnajit Mittra, Principal, Project VeriPage. It is distributed under Lesser GNU Public License (LGPL) Agreement. The website for this project is located at the SourceForge Network.