Tutti II: The Tape-Enabled Tomy Tutor Emulator
Finally: the first Tomy Tutor emulator to load and save tape image files
you can transfer to and from your real Tomy Tutor.
This section is under development. Last modify 22 June 2016.
Back to the XTOMYDEV page
| Back to the main page
Something old becomes something new
Tutti II is the spiritual successor to the original Tutti simulator, the
first attempt to model the Tomy Tutor on another platform (in this case,
the Commodore 64). However, it is also the actual successor to another
older emulator, Ian Gledhill's TutorEm, as it
is in fact based on its source code, just with bug and endian fixes,
and upgrades for performance. This makes it a descendant of
some of the oldest attempts to emulate this unusual computer.
Tutti II is not designed to replace MESS's
Tutor driver, which currently
has the best 9918ANL and DCSG video and sound emulation, and is the only
emulator to support cartridge images. If you're just looking for something that
plays Traffic Jam, for example, this is not the emulator you want.
Tutti II is a programmer's emulator for hacking the Tutor on its own terms.
Besides being currently the only emulator that reliably loads and saves to
emulated cassette -- using
XTOMYDEV-format bitstreams which can be transferred to and
Data Recorder and then the real Tomy Tutor -- it also offers the excellent
TutorEm debugger, the ability to decouple the VDP for better responsiveness,
a turbo processing mode and the ability to snapshot the running system.
Tutti's cassette acceleration reads and generates bit-exact bitstreams that are
perfect representations of the computer's output in just seconds,
even on slow systems.
Tutti II is available under the New BSD license.
Copyright © 2003, Ian Gledhill.
Copyright © 2015, 2016 Cameron Kaiser.
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- Redistributions of source code must retain the above copyright
- notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright
- notice, this list of conditions and the following disclaimer in the
- documentation and/or other materials provided with the distribution.
- Neither the name of the nor the
- names of its contributors may be used to endorse or promote products
- derived from this software without specific prior written permission.
What Tutti II currently supports (and doesn't support)
Tutti II supports:
Tutti II does not support (yet? -- roughly in priority order):
- Any Mac running 10.4 or higher (PowerPC or Intel), including El Crapitan`
- Full 9995 emulation
- Highly compatible 9918A emulation
- Full accelerated
support for cassette (to and from XTOMYDEV bitstreams) in both
GRAPHIC and BASIC mode
- Built-in debugger
- Stand-alone ROM disassembler utility (dutti)
- Built-in "snapshot" freeze facility
- Turbo mode for balls-to-wall processing
- Decoupled from VDP frame mode for better responsiveness
- Joystick and/or joy controllers. This is the highest priority for the
next release. However, you can simulate the
joy controllers with certain keypresses.
- Sound/SN76489AN DCSG support. Currently there is no sound support
at all in Tutti II. This is the second highest priority for future
- Windows, Linux or other operating systems. Although TutorEm was originally
a Windows emulator, I don't have access to a Windows compiler, so this time
around Tutti is Mac-only to begin with. The system
dependent portions are in osx/. Since Tutti II is also based on
SDL 1.2, it should be very portable to many other systems and I would love
to accept your ports assuming they do not break the core Mac port. You will
need to add the system dependent portions, such as the GUI and tape and
- Many interrupt locations are still not understood. Because of this,
the 9995 subsystem actually traps execution at certain locations and
simulates the operation instead.
- Other ROMs such as the Pyuuta and Pyuuta Jr.
systems. I would like to support these, but those same system integration traps
expect certain code entry points. The same emulator core could be used with
modification for these different points once they are disassembled.
- I/O or parallel port. (Emulating the printer port shouldn't be hard,
Using Tutti II
The Tutti II application encapsulates the necessary ROMs and all libraries,
so just start it up. Because Tutti II includes
copies of the Tomy BIOS, legally you can only use this emulator if you are
entitled to do so, such as by already owning a Tomy Tutor. The
Tutor 256x192 display will appear.
The Tutor keyboard is fully emulated in its original positions
(keyboard layout permitting). That
means double quotes on
SHIFT-2, parentheses on SHIFT-8/9, equals sign on SHIFT-0,
etc. The handaku (°)
key is on the plus/equals key, and the underscore is on
the tilde/backtick key. In addition, the Tutor puts the colon key
next to the semicolon key.
With respect to Tutor-specific keys,
LOCK is mapped to LEFT CONTROL, MOD to RIGHT CONTROL or RIGHT
OPTION or keypad ENTER (to faciliate laptop layouts that may be missing
some of these keys), and MON to
backslash. As a convenience, DELETE is also mapped to the left arrow key
so that you can (sort of) backspace, and both SHIFT keys are mapped to
the Tutor's single SHIFT key.
Tutti also defines certain specific keys for special functions, which you
can also access from the pull-down menus:
- Command-R resets the emulator. Any program or data is lost.
- Command-V pastes what's on the clipboard into the emulator as keystrokes.
The emulator is smart enough to toggle the ALPHA LOCK to support lower case
and pasting works in both GBASIC and BASIC modes. Most characters are
transparently converted, assuming there is a Tutor equivalent. Characters
the emulator cannot translate are emitted to standard error (and/or the
system console depending on how you run the emulator). Be sure ALPHA LOCK
is enabled (i.e., the default uppercase), or the emulator may become
confused with mixed case text.
F1 launches the integrated debugger (at the next available safe
instruction, which may not necessarily be the spot of the foul). By default,
the current instruction is displayed with the contents of memory, the
three CPU registers, and the 16 workspace registers (as referenced by WP).
While in the debugger, you can then do the following:
- E exits back to normal execution.
- F1 single-steps through code in the debugger.
- F2 resumes execution automatically, but in the debugger. To stop, press
- F7 toggles emitting the instruction stream to standard output, which
you can monitor depending on how you've started the emulator.
- The arrow keys scroll the memory display (by default the scratchpad
RAM at >F000). PAGE UP/DN jump bigger jumps.
- By default, CPU-space is displayed (what the 9995 sees). To see VDP RAM
and registers, press V. To return to CPU memory and registers, press C.
- F5 saves the current state of the emulator to a file. A file picker will
appear to select the filename. This is not the same as saving
to emulated tape (see below).
- F6 loads the current state of the emulator from a file. A file picker
will appear to select the filename. This is not the same as loading from
emulated tape (see below). Picking a file that is not an emulator
state or is corrupted
will likely be deleterious to your session. Unlike tape loads and
saves, a saved emulator state file
is specific to the endianness of the host that generated it:
you cannot restore a saved
snapshot made on a Power Mac on an Intel Mac, and vice versa.
- Command-B toggles the speed throttle ("Turbo Boost"). When turbo
is off (default), Tutti II emulates the Tutor roughly at its original clock
speed, inserting nanosleeps between instructions as necessary. When turbo
is on, no nanosleeps are inserted, which unthrottles the clock speed;
if the VDP is also decoupled from the CPU (next
option), the system won't wait for screen updates either.
Useful for slow code. This mode is automatically turned on and off
for tape operations (see below).
- Command-L toggles locking to the VDP frame. When locking is on
(default), the VDP IRQ is locked to an approximate NTSC
framerate, and an appropriate number of CPU cycles are allocated to
each frame. When locking is
off, the CPU is decoupled from the VDP
and the VDP IRQ is activated as rapidly as possible up to a
maximum of approximately 1/600s. This makes the emulated
Tutor more responsive to keyboard
input and certain other tasks (for example, drawing by hand is much
nicer in GRAPHIC mode this way), and enables the CPU to run at breakneck
speed when Turbo mode is also enabled (above), but may
interfere with some programs expecting exact timing and some keys may
repeat too easily. This mode is automatically turned on and off for tape
operations (see below).
- Command-S stops the emulated tape if the emulator has not detected the
end of data. Normally this isn't necessary (see below) and this option is
- Command-Q exits the emulator.
When Tutti II detects cassette activity, it automatically attempts to
link it to a bitstream file. For example, if you have a BASIC program
written and you attempt to save it with the SAVE command within the
emulator, a file picker will automatically
appear to select where the XTOMYDEV bitstream should be written. Once you
select the file, the emulator will reduce screen updates and unthrottle
the CPU, causing most tape operations to complete within seconds. After
the save has completed, the emulator will return to previous settings.
Similarly, if you attempt to LOAD a file from within the emulator,
the file picker will appear to
select which XTOMYDEV bitstream you will use as emulated tape input. If
you give a filename argument to the LOAD command,
the Tutor will scan the bitstream for that
filename specifically; if no filename is given, the Tutor loads the first
file it finds, which is usually what you want because
if the filename is not found, an error message will appear in the emulator.
In GRAPHIC mode, the filename is required but the
emulator doesn't care (see Known bugs).
Tape operations function identically in both GRAPHIC and BASIC modes,
and Tutti II can detect tape activity in both environments. The tape
acceleration is extremely quick if I do say so myself. Even on my
relatively slow 1GHz iMac G4, a GRAPHIC LOAD or SAVE takes only about three
seconds; it's practically instantaneous on my Quad G5 and my i7 MacBook Air.
Compare this to over six minutes on a real Tutor!
Typically tape operations are automatically stopped and started by the
emulator for you while Tutti II monitors tape IRQ activity. However, if the
Tutor reacts badly to a tape operation, or the emulator fails to detect
that a tape operation is finished, you may need to stop the
emulated tape with Command-S to regain functionality.
The dutti disassembler
Tutti includes dutti, a command-line disassembler for the Tutor
ROM, within the application package. Run it from the Terminal prompt with a
starting and ending address (decimal, or hex if prefixed with 0x).
Addresses should end on word boundaries. Make sure the tutor*.bin
ROM images are in the same directory.
Other than what Tutti II doesn't yet support (sound, more than four sprites,
joy controllers/joystick, etc.),
the following bugs are known:
Send comments and new bug reports to
firstname.lastname@example.org. Please, no
attachments unless requested.
- The SOUND() command generates * ERR 2 in BASIC. This
appears to be a bug in the CPU emulation, but BASIC being written in Tomy
GPL makes this really hard to figure out. (This bug is also present in
- The border is not emulated or displayed. This is not really an issue
for BASIC or GBASIC, however, where the border is almost always the same
as the background colour.
- Loading a defective snapshot may crash the emulator as well. Many of the
weak points have been found ... but probably not all.
- The GRAPHIC LOAD trap will load the first file it finds, even if it
doesn't match the filename you provide (a real Tutor will throw a
FORM ERR). This is considered a "feature."
- Failed LOADs in BASIC trigger * ERR 19 in a way that is not
entirely devoid of side effects.
Download the emulator (504K zipped Mac app),
compatible with any Mac (PowerPC or Intel) running 10.4 or higher. It is
tested on Tiger (PowerPC), Snow Leopard (i386) and El Capitan
app is not signed, so 10.7+ users may need to adjust your security settings
when running the app for the first time.
Download the demo tapes (26K). This includes
five bitstreams as a demo:
a black and white dithered image of Georges
Sunday Afternoon on the Island of La Grande Jatte
generated with XTOMYDEV for GRAPHIC mode (load "BITM"),
a "GRAPHIC 64" colour dithered image of the same painting
also generated with XTOMYDEV (load "PICT"),
a "GRAPHIC 64" colour dithered image of the lovely lady named Jayne
shown at left also generated with XTOMYDEV (load "PICT"),
James Host's Colour Bars and 32 Sprites demos for BASIC (load "BARS"
and "SPRITE" respectively).
Download the source code (warning: includes
resource forks) (1.3MB). This includes all media assets and the special
universal SDL dylib Tutti uses for maximum compatibility.
To build the universal OS X binary requires
Xcode 2.5 or 3 (with the 10.4 SDK installed) and exactly SDL
1.2.14. Install the 1.2.14
developer framework and just type make.
1.5 - Bug fixes and new features:
1.2 - Initial release as Tutti II.
- support for paste as keystrokes
- AltiVec acceleration (G4/G5) for 9918 emulation
- 2x display (software on Intel/G3, AltiVec scaling on G4/G5)
- multiple fixes to the 9995 core
- display list 9918 sprite algorithm is now scanline correct
- fix crash in tape save dialogue
- faster writes to memory-mapped I/O
- enabled _/@ key (mapped to backquote key)
- additional alternate MOD key for keyboard without Right-Opt (iBook G4, etc)
to numeric keyboard ENTER
- you can use both shift keys now (both map to "SHIFT")
- further improvements to timing loop
- debugger can emit instruction stream to stdout (toggled with F7)
- Command-M actually does minimize the window now
- 9995 STWP instruction correctly disassembled
- fix visual glitch with "2" glyph in debugger
1.0 - "Initial release as TutorEm" (for internal bookkeeping only).
Back to the XTOMYDEV page
| Back to the main page