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This is release 9.7 of irsim.

Compilation and installation

The make script has been changed to work similarly to the magic-7.3 GNU autoconf make. To make the default IRSIM version, which includes Tcl/Tk (if available) and OpenGL (if available), do:

./configure
make
make install

Running IRSIM under Magic

Standard magic version: See the magic tutorial #11 (document "tut11.ps" in the magic source distribution).

Tcl-based magic version and Tcl-based IRSIM (irsim-9.6):

Run the Tcl version of magic in the usual manner. As an example, consider "tut11a" used in tutorial #11 for demonstrating IRSIM.

magic -w -d OGL tut11a

Start IRSIM with:

irsim

This is a Tcl procedure which can guess at default values. Magic starts up with a definition for the procedure which looks for the "irsim.tcl" script in the CAD_ROOT install directory. Assuming that magic and irsim are installed in the same CAD_ROOT root (e.g., /usr/local/lib or /home/cad/lib), this file will be sourced, and IRSIM will be ready to run. If not, it will be necessary to run "source /irsim.tcl" by hand, substituting the actual install path for IRSIM.

If a layout is loaded into magic, it is assumed to be the circuit to be simulated. If .ext and/or .sim files don't exist for the circuit, they will be created.

The full syntax is:

irsim [parameter_file [sim_file]]

where "parameter_file" is an irsim ".prm" file from the IRSIM library install directory, and "sim_file" is a .sim file, presumably generated in magic by "exttosim".

At this point, if all goes well and no errors occurred, all IRSIM commands will be available under magic. Additional commands are added when running irsim under magic. These are:

watchnode [node_name [style_name]]
	Display a node's simulation value on the layout.  If
	no name is given, find the node under the box and
	display its value.  The style name is one of magic's
	display styles from the ".dstyle5" file.  The default
	is "white".

unwatchnode node_name
	Erases the node value from the layout.

movenode node_name
	Node values normally appear positioned at the point
	found by the magic "goto" command.  If this is a
	poor choice, the node can be moved to a position
	centered on the magic cursor box using this command.

watchtime
	Causes the simulation time to be drawn on the layout,
	centered on the magic cursor box's current position.

unwatchtime
	Erases the simulation time from the layout.

movetime
	Moves the position of the simulation time text to be
	centered on the current position of the magic cursor
	box.

For example, with layout file tut11a.mag, after invoking "startirsim", do:

watchnode bit_0
watchnode bit_1
watchnode bit_2
watchnode bit_3
watchnode RESET_B black
watchnode hold red3

vector clk phi1 phi2
vector clkb phi1_b phi2_b
clock clk 10 00 01 00
clock clkb 01 11 10 11
vector bits bit_3 bit_2 bit_1 bit_0
w clk hold RESET_B bits

c
l hold
l RESET_B
c
h RESET_B
c
c
c

The values are drawn on the magic layout in time with the simulation. Note that "source tut11a.cmd" is a valid command. The .cmd file that comes with the tutorial should be okay as-is. However, note that several commands in IRSIM are not legal Tcl syntax, and have been changed. Any of these commands in a file must be changed to match before the file can be sourced. Also, some commands in IRSIM are already defined as Tcl commands. These are: time, set, and clear. To get the expected behavior in IRSIM, they must include the namespace: irsim::time, irsim::set, irsim::clear. "exit" is a trivial overloaded command. "clock" is also overloaded, but because the IRSIM and Tcl syntax for "clock" are mutually exclusive, the command is handled by IRSIM and checked for which version of the command is intended.

Note that it is possible to display vectors on the magic layout. Position the box to an empty area of the layout and type:

watchnode bits

Similarly, you can postion the box to another empty area and do:

watchtime

to get the simulation time display printed on the magic layout. You do not need to know the name of a node in order to see its value. For instance, select a random piece of the layout and type "watchnode". The node value will be displayed at the position of the selection.

To simply query a node value (without selecting it for display), use the 2-argument form of "assert", combining IRSIM and Magic commands. Select a bit of layout paint, and do:

assert [getnode]

Under irsim, the "display" command has an additional option, "tclproc".

display tclproc proc_name
display -tclproc

when proc_name is specified, the IRSIM "d" command will invoke the specified Tcl procedure instead of printing values to the screen. The procedure will also be called whenever node and vector values in the watch list ("w" command) are updated. This method allows signal names, values, and times to be captured and used by other programs. "watchnode" makes use of this method to write simulated node values back into the magic window.

The syntax of the Tcl procedure is:

proc proc_name { name value time } {}

This procedure is called internally from IRSIM. "name" will be given the name of the node or vector being watched. "value" will be given the value of the node or vector. "time" will be given the current simulation time in nanoseconds. Note that this procedure is always called at least twice, with the last call being name="curtime", value="t", such that procedures may defer printing the time value until all watched node values have been displayed. Only the last call to the procedure will return its value to the interpreter.

Release Notes

The calibrate directory contains information on creating your own prm files.

Release 9.5+ includes the software to perform incremental simulations, which can also be used to create an incremental-fault-simulator. To make the fault simulator, you will have to do it by hand: First use the make_irsim script to build irsim, then (before cleaning anything in irsim) go into the src/fsim directory and run make. This will create the program called "ifsim", which you can use to run statistical simulations of stuck-at faults. The directory src/fsim/doc contains both latex and PostScript versions of the documentation needed to use ifsim.

Release 9.5 also includes the following extra code:

1. Power estimation code through toggle counts (written by Don Ramsey) The code is not completely debugged yet (?) but there is demand for it from a lot of people. It can be turned on/off selectively through the "make config" script. See the file man/powerEst.doc for details on how to use this.

2. Code that enables the user to write their own subcircuit models for "analogish stuff". (written by R. Gonzales and S. Sidiropoulos). Again it is enabled in "make config". An example pll is in src/irsim/UserSubckt

3. Some extra commands (assertWhen and until) which may help debugging of asynchronous designs

4. Fixes for Linux displays (M. Godfrey)

Release 9.6 includes the following new features:

5. Tcl-based IRSIM (T. Edwards)

6. Threaded X11 graphics (no anXhelper!) (T. Edwards)

7. Makefile configuration support for Mac OS-X, Solaris, and Cygwin.

8. Pseudorandom number generator for the Tcl version (T. Edwards)

Release 9.7 includes the following new features:

9. GNU autoconf-base "make" process equivalent to that of magic-7.3

10. Tk-based Analyzer window, including a full set of command-line commands for manipulating the analyzer.

11. Verilog testbench-like commands "at", "every", "when", and "whenever"

12. Command "settle" to handle problematic tight loops (e.g., back-to-back inverters in flip-flops) by waiting a certain period before setting a node undefined.

13. Command "relax" to handle problematic large loops (e.g., flip-flop/ multiplexer loops) by forcing initial conditions.

14. Ability to handle multiple circuits by placing each in its own namespace.

15. Ability to define and set nodes that are not part of an input circuit.

16. Simplified vector definitions and setting, including handling of decimal and hexidecimal notation, and specifying numerical ranges in a vector name (such as "vector D D0:8")

17. Tcl procedure-based user-defined subcircuits.