FM Towns PC ODE - Grey Tower Wizard Installation Notes And Review

The Gray Tower Wizard is an Optical Drive Emulator (ODE) for FM Towns PCs, not to be confused with the FM Towns Marty (which is a stripped-down and consolized version of the PCs) or the Doc Brown ODE for Marty (which is made by the same person).  The FM Towns PCs have dual floppy drives and the ability to add RAM which makes them capable of running more complex or resource-heavy games than the Marty.

How Do You Get One?

The kit including shipping ran me 150 Euro.  Ordering one is basically the same process as the GDEmu, Rhea, Phoebe and Doc Brown.  I had never ordered anything from Deunan before but I'm more than familiar with the popular complaints about it being difficult.  It's not like ordering something from Amazon, but I didn't find it to be very difficult at all.  

I signed up for blog updates, waited until he announced he was going to sell them, then refreshed the Wizard Ordering page until he activated it.  When he did, the ordering page changed to a form to submit an order request.  There was a part availability issue and I needed to select whether to wait for the correct part or ship as-is and work around an incorrect part.  I elected to wait.  As soon as the part came in and Deunan was ready to ship I received a PayPal invoice matching the characteristics the ordering page describes.  I paid it and a little less than two weeks later the Wizard was in my hands. If you take the time to read Deunan has worked the entire process out.

Features

• Retains full function of the CD-ROM drive - this is an awesome feature as it makes the Wizard a net add without any functionality lost.
• CMOS Battery Solution - it's super annoying to replace the CMOS batteries in these PCs but the Wizard makes it a breeze.
• Quick Boot Options for faster loading.  I haven't tried these yet, but they're experimental.
• *Can take advantage of 486 CPU cache and wait state skipping to significantly increase performance.

What Comes In The Kit

The kit is somewhat less install-ready than other ODE kits I've reviewed, but if you followed Deunan's development notes you would understand this mostly has to do with obsolete connectors on the FM Towns itself.

The kit comes with:

• Wizard ODE PCB
• 2x white 3-pin socket
• 2x white 3-pin plug
  
• 4x white 10-pin socket
• 4x white 10-pin plug
• 1x Row of 10 metal inserts for 3-pin plug
  
• 4x Row of 12 metal inserts for 10-pin plug
• 1x DPST switch

Installation

Before installing you should consult the official installation guide.  What I've written below is intended to expand on those original instructions, NOT to replace them.  Always refer to the official guide as it will be updated as needed, this one may not.

Disassembling the FM Towns

As I've already created an illustrated guide to disassembling the FM Towns, I'm just going to describe the steps here.  See the guide if anything isn't making sense. 

You'll need a cruciform (Philips) screwdriver.

1. Move the locking tabs on the left panel to the down position, then pull the left panel off.  
2. Use a plastic pry tool or fingernail to remove the screw cover on the top front center of the tower.
3. Remove the screw.
4. Remove the Floppy Drive cover by pulling straight out.
5. Remove the two screws in front and back of the carrying handle on the top panel.
6. Release the top panel by pushing back on the retaining clip just above the floppy drives, then tilting upward.
7. Remove the floppy drives by pressing down and pulling out on the clips on either side of each drive.
8. Remove the screw beneath the floppy drive bays.
9. Disconnect the two ribbon cables, and three red and brown wire bundles from the PC.
10. To remove the CD-ROM enclosure, reach in to the cavity and pull the locking tab to the left while pulling outward on the front panel.

Once you have the CD-ROM enclosure free you'll need to break it down a little further

1. Use a hair dryer or some other gentle source of heat to soften the adhesive on the black fabric tape affixing the ribbon cables to the left side of the CD-ROM assembly.
2. Gently peel the tape away being careful not to strain the ribbon cables.
3. Remove the two recessed screws near the bottom of the assembly.
4. With the screws removed press down on the locking tabs near the top of the assembly and pull the front plate off.
5. Place the CD-ROM drive door-side down and remove the four screws affixing the mounting frame to the drive.
6. Separate the drive from the mounting frame

You should now have enough access to the CD-ROM Drive PCB to begin the next step.

Removing the Original Sockets

In order to minimize the amount of disassembly and soldering involved, you need to re-use the sockets that connect the CD-ROM to the PC's interface board. The original sockets need to be reused because they are long since obsolete.  This will allow you to connect the Wizard to the PC using the same cables that originally connected the CD-ROM.

1. Disconnect the cables from the three white sockets at the bottom of the PCB.  Note that the brown wire indicates Pin 1 on each connector.  It's important to track of Pin 1 for building the replacement cables correctly.

2. Carefully de-solder all three of the original connectors.  I strongly recommend only doing this if you have the right tools and are practiced in using them.  I used an Anesty ZD-915 De-soldering station set to 630 degrees Fahrenheit. Since these are not plated through-hole connectors they are easier to de-solder than many other components - so you could easily use a de-soldering braid instead.  What makes this difficult is that these sockets are made of plastic which is easily deformed if you apply too much heat, leave heat applied for too long, or press on the pins while hot.  You may loosen or bend a pin if you're not careful and it will not be easy to re-solder the connector in a usable way if you do.  Note that some of the pins are bent on the PCB side by the factory to help hold them in place to be soldered on, however it is not necessary to un-bend them to remove or re-install them.

Installing the Old Sockets onto the Wizard

1. Solder the original connectors to the Wizard in the position and orientation shown.  This will ensure that the pin order is correct when you use the cables that used to go to the CD-ROM drive to connect the Wizard to the PC.  For reference, Pin 1 for each connector is the right-most pin.

Note: I probably should have plugged the cables into the 10-pin connectors when soldering them to the Wizard to ensure that the pins were aligned straight.  If you'll notice in the image above some of the pins aren't perpendicular to the board.  The connectors have a little bit of tolerance for this though and still connected just fine.

Installing the New Sockets and Switch onto the Wizard

In order to connect the CD-ROM drive to the Wizard for pass-through mode, you'll need to install three new-style sockets across the bottom of the Wizard.

1. Solder in the supplied sockets in the orientation shown.  Note: pin 1 on all three sockets is the rightmost pin.  Again this is important to remember when assembling your cables.

2. Solder the ODE/CD-ROM selector switch into the spot marked "Select".

Installing the New Sockets onto the CD-ROM

1. Solder in the supplied 10-pin and 3-pin sockets in the orientation shown.  Note pin 1 on all three sockets is the leftmost pin.

Building the CD-ROM Cables

Now for the fun part - constructing your own cables. This is by far the most tedious part of the entire process.  You could save a considerable amount of time by directly soldering wires from the CD-ROM to the Wizard instead of building cables, but you're also creating a hassle if you ever want/need to remove the Wizard later.

1. Select your wire.  For mine I went with a silicone insulated wire because the insulation doesn't shrink or melt when it gets hot so it's much easier to control the length of the wire.  I do not recommend using ribbon wire as the insulation shrinks when heated and will actually be more difficult to work with. Your pin 1 wire should be a different color for easy identification.  I went with red and black because it was as close as I had to the red and brown of the original cables.

2. Cut 23 equal length wires, 3 of which should be a different color from the others to distinguish "pin 1".  I found 10.5 cm to be the perfect length for this.

The kit comes with 5 strips of metal inserts which are used to connect the wires to the sockets.  One strip has noticeably larger inserts and it's is meant for populating the 3-wire cable.  The remaining four strips are for populating the 10 wire cables.

I'm not certain what the prescribed method of using these connectors is.  There might be a guide out there that does a better job of showing you the "right" way to use these.  I have been using connectors like these to build my own cables for years so what I'm going to share is simply how I do it.

Each connector has three sections. The section in front is the receptacle for the pin, the section in the middle is meant to pinch the exposed wire, and the section at the back is meant to crimp and and hold the wire jacket in place.

On the reverse side of each connector is a notch that's used for holding it in place once it has been inserted into the plug.

3. Cut one of the connectors free but leave part of the metal strip attached.

4. Bend the metal strip back at a 90-degree angle.  This will make it easier to hold on to while it is manipulated.

5. Use a clamp or "third pair of hands" to hold the insert in place.

6. CAREFULLY apply a drop of solder to the "wire" area of the insert. I usually do this by touching a clean soldering iron tip to one side of the wire area while I touch the center with a strand of solder.  You do not want to get any solder forward of the wire area as doing so may block the pin from inserting fully. (I believe the intended purpose of the "wire" area is to crimp the wire in place rather than solder it, however I really don't trust that would hold reliably.)

7. Solder the pre-tinned wire to the "wire" area. Be careful that the wire is not positioned forward into the pin area as it may block the pin from inserting fully later on. Once it's soldered, give it a good backward tug to make sure the joint is secure.  You DO NOT want to try to fix a cold joint here after the fact.

8. Take a pair of pliers and twist the tabs that will crimp the jacket so that they're slightly diagonal to one-another. You may need to hold a finger next to the shaft while you do this to keep it from bending too.  The idea here is that you want the two tabs to be offset so they'll lay next to each-other when you crimp them down.

9. Use a pair of precision pliers to fold down and crimp the jacket holding tabs.  (You'll need to make sure they're a little flatter than what's shown in this picture.)

10. Using flush cutters, trim off the metal strip from the shaft. Try to get it as flat as possible as you won't want metal flashing sticking out the back of the plug.

11. Starting with your Pin 1 wire, insert the metal shaft into the plug in the proper position.  Check, double check, then triple check that you've got the right position before doing this.  These connectors are keyed so they should only go in one way, but just to be safe make a point to align them with the notch toward the side of the plug with the catch for it.

The key to doing this is to take your time and not rush.  If one of the metal shafts doesn't want to go in, make sure you don't have it oriented backwards, or check the jacket crimp tabs to make sure they're flat against the shaft.  

12. To ensure that you wire everything up correctly, I recommend connecting pin 1 to each end plug first, then doing each subsequent pin in order one at a time.

I used a section of heat-shrink tubing to keep the wires tidy as I connected them. When you're done, you should have something like this.  Note that the position of pin 1 is always the same no matter which way the cable lays.

Checking It Twice

When you've finished constructing your cables (or soldering wires if you took the lazy route) you want to make sure everything is not only wired correctly but connects securely.

1. Use the newly constructed cables to connect the Wizard to the CD-ROM drive. While you're doing this, check that the plugs fit fully and securely into the sockets.

2. Flip everything over and use a multi-meter continuity tester to ensure that all of the pins are making good connection like they should be.  Note that in this position, the connections should be exactly parallel, so you can start from one side and work your way to the other ensuring that each pin is connected to its counterpart.

Installing the CMOS Battery Connector

The Wizard comes with the convenience of socketed connectors for the CMOS batteries.  The original batteries are soldered on to the connector and not simple to change.

1. Cut the wires from the original batteries, strip the ends then solder them to the "BATT" connector according to wire color. R=Red, B=Black, O=Orange, W=White.

2. Install the batteries.  It should be obvious which battery belongs in which holder according to its thickness, but for reference the CR2430 goes in the left socket, and the CR2450 goes in the right socket.

Mounting the Wizard

The Wizard PCB has been keyed to fit on the back side of the CD-ROM mounting frame, but there are no standoffs towards the top of the frame so it will need a little help to stay snug.

1. Place some padding along the top part of the CD-ROM mounting frame to serve as standoffs.  I happened to have some felt furniture pads laying around which is exactly what Deunan recommended.

2. Push the Wizard in place, making sure to align the PCB with the clips and standoffs on the mounting frame.

3. Attach the original CD-ROM cables to the Wizard.

Congratulations, you're now ready to re-assemble the FM Towns PC.  

The original cables are physically interchangeable so you want to be careful not to mix them up.  The plugs are stamped with a connector ID on each end to help you keep this straight when plugging in the original CD ROM Drive.

Plug the "1" end of the "1 and 10" cable into the socket on the Wizard marked "CN10" and plug the "2" end of the "2 and 9" cable into the socket marked "CN9" on the Wizard.  What you want is for the far end of the cable to match the ID of the socket it's plugged into.  

Operation

Prepping the SD Card

The official operation guide does a fairly good job of explaining how the file system needs to be laid out on the SD card.  If you've ever used one of Deunan's other ODEs this will be familiar territory. Each image needs to be in it's own sequential numerically named directory.  A button on the ODE is used to switch between images.  Alternatively a menu program (called "Spellbook" in this case) can be installed as the first image to allow you to directly select different games by name.

As of this writing the official guide omits the need to format all SD cards as FAT32.  Cards larger than 32GB are pre-formatted as exFAT, and if you try to re-format the card in Windows it will only let you select exFAT.  Unfortunately exFAT requires a license to legally use so it's cost prohibitive to support.  If you use a card larger than 32GB you'll need to use a tool like GUIformat or format the card from Linux to write a FAT32 file system.

If you attempt to use a card formatted with exFAT, the yellow light on the Wizard will light and stay on indicating an SD card read error.

If you're trying to use guiformat to reformat your SD card in Windows, you may encounter an issue where Windows won't let the tool have access to the SD card to format it.  If this happens, right-click the SD card drive in Windows and tell it to Format.  Uncheck "quick format", click "start" then quickly pull the SD card out of the slot.  This will corrupt the file system and stop Windows from mounting it which should let guiformat have the access it needs to lay down a FAT32 file system.

Converting BIN+CUE to Something Useful

The Wizard does not support BIN+CUE because it is not a consistent standard.  See technical details for supported image formats.

Most of the FM Towns CD images I have and have made are in BIN+CUE format.  

Rather than re-rip everything or look for alternative software collections I used the excellent SBITools utility.   It seems to have been written to convert PlayStation images, but it produced perfectly working Clone-CD (CCD) format images from Redump BIN+CUE images.  So far every game I've used this on has worked perfectly.

Usage is fairly simple. You dump your BIN+CUE CD image into a directory and use a provided batch file to process the image.  Each converted image will end up under the "CCD" directory with a subdirectory named after the basename of the .CUE file.

To use it:

1. download one of the SBITools zip files from "Releases" and extract it.
2. Copy the "sbitools.exe", "psxt001z.exe", and "CUE2CCD.bat" files to the directory where you have your BIN+CUE images.
3. From a command prompt run: "CUE2CCD.bat *.cue"

It's that simple.

SpellBook

Setting up Spellbook is described in the official documentation, but I'll summarize it here.  You'll place Spellbook in directory "01" to ensure it's the first thing that the Wizard executes on startup.

Once you have your file system arranged how you want it, you'll need to create a text file "title.txt" in each directory with the name you want the menu to display for that image.  

When all of your directories are created and all of your title.txt files are populated you'll run a small Windows executable to scan all of the title names, create a menu and generate a small ISO file for the menu.  Any time you add/remove/rename a directory you'll need to re-run the tool to regenerate the ISO with the new menu.

The Spellbook interface is very lightweight and basic.  You navigate with the direction pad.  Up and down moves up and down, right and left page forward and back.  The "Select" button brings up a brief status menu that shows the version of Wizard firmware, the PC's serial number, the detected CPU etc...

Starting a game with A will launch it normally, starting it with B will launch with performance options such as reduced wait states or "FAST" mode depending on the detected hardware.

Unfortunately Spellbook only supports the basic default game pad.  It doesn't support the keyboard (though that is on the list as a future feature).  It also doesn't support the Capcom CPSF adapter - you can kind of move around in the interface but the buttons are all wrong - probably due to a different polling or encoding.  With the Popolon JoySNES adapter SpellBook seems to think the select button is being held down so it goes into the status menu and won't let you exit.

Conclusion

The Grey Tower Wizard is a great step forward for FM Towns PCs both in terms of making the library more accessible and in terms of preservation.  It's a fantastic upgrade that doesn't make you decide between being able to load games from CD or SD, and as I'm crazy enough to have upgraded the CPU on my 20F I really love how easy this makes it to take advantage of a 486 CPU (as long as you remember to launch games with the "B" button instead of the "A" button). One example is that I can now play Super Street Fighter II at normal speed without having to resort to shutting off Raster mode.