sim65 is used as part of the toolchain to test 6502 or 65C02 code.
The binary to test should be compiled with
--target sim6502 or
The simulator is called as follows:
Usage: sim65 [options] file [arguments] Short options: -h Help (this text) -c Print amount of executed CPU cycles -v Increase verbosity -V Print the simulator version number -x <num> Exit simulator after <num> cycles Long options: --help Help (this text) --cycles Print amount of executed CPU cycles --verbose Increase verbosity --version Print the simulator version number
sim65 will exit with the error code of the simulated program, which is limited to an 8-bit result 0-255.
An error in sim65, like bad arguments or an internal problem will exit with
A timeout from
-x will exist with
Here is a description of all the command line options:
Print the short option summary shown above.
Print the number of executed CPU cycles when the program terminates.
The cycles for the final "
jmp exit" are not included in this
Increase the simulator verbosity.
Print the version number of the utility. When submitting a bug report, please include the operating system you're using, and the compiler version.
Exit simulator after num cycles.
The simulator will read one binary file per invocation and can log the program loading and paravirtualization calls to stderr.
Example output for the command
sim65 --verbose --verbose samples/gunzip65
Loaded 'samples/gunzip65' at $0200-$151F PVWrite ($0001, $13C9, $000F) GZIP file name:PVWrite ($0001, $151F, $0001) PVRead ($0000, $FFD7, $0001) PVOpen ("", $0001) PVRead ($0003, $1520, $6590) PVClose ($0003) PVWrite ($0001, $13D9, $000F) Not GZIP formatPVWrite ($0001, $151F, $0001) PVExit ($01)
For a C test compiled and linked with
--target sim6502 the
command line arguments to
sim65 will be passed to
and the return value from
main will become sim65's exit code.
exit function may also be used to terminate with an exit code.
Exit codes are limited to 8 bits.
The standard C library high level file input and output is functional.
A sim65 application can be written like a command line application,
providing arguments to
main and using the
Internally, file input and output is provided at a lower level by a set of built-in paravirtualization functions ( see below).
Assembly tests may similarly be assembled and linked with
--target sim6502 or
Define and export
_main as an entry point,
and the sim65 library provides two ways to return an 8-bit exit code:
_mainwith the exit code in
jmp exitwith the code in
The binary file has a 12 byte header:
$73, $69, $6D, $36, $35or
spused by the paravirtualization functions
Other internal details:
$FFFCwill be pre-loaded with the given reset address.
$FFF9. Jumping to this address will terminate execution with the A register value as an exit code.
JSRto one of these addresses will return immediately after performing a special function. These use cc65 calling conventions, and are intended for use with the sim65 target C library.
NMIevents will not be generated, though
BRKcan be used if the IRQ vector at
$FFFEis manually prepared by the test code.
sim65 (and all cc65 binutils) are (C) Copyright 1998-2000 Ullrich von Bassewitz. For usage of the binaries and/or sources the following conditions do apply:
This software is provided 'as-is', without any expressed or implied warranty. In no event will the authors be held liable for any damages arising from the use of this software.
Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the following restrictions: