Super Game Boy Compatibility Modification for Tri-Star/Super 8, Backup ====================================================================== Devices and Universal Adapters (rev. 0.5 24-Mar-98) ============================== This document is copyright © 1998 by Mark Knibbs . The latest version, and several other console-related documents, should be available from my web page at: http://visitweb.com/mark You are explicitly permitted to include the *unmodified* document on web sites, FTP sites and the like. But it is best to simply link to the document on my web page, as this means that you automatically pick up any changes made. If you have any comments, suggestions or questions about this document, please contact me. Introduction ------------ The Tri-Star/Super 8 adapter is an accessory for the Super NES/Super Famicom, which allows most 8-bit NES and Famicom games to be played. It also has a pass-through connector to allow SNES games to be used without removing the unit. For more information, see the Tri-Star/Super 8 FAQ on my web page at: http://visitweb.com/mark Normally the Super Game Boy is not compatible with the Tri-Star/Super 8 or some backup devices, such as the Super Wildcard. It runs at a fraction of the proper speed. This document details a simple modification that you can perform on your Tri-Star/Super 8, backup device or universal adapter to allow the Super Game Boy to work properly with it. I do not currently own a backup device, so the instructions given here only apply to the Tri-Star and Super 8. However, it is likely that the procedure for backup units is identical or very similar. Likewise, the Super Game Boy is incompatible with some universal adapters. If your SGB runs very slowly when used with your universal adapter, you can apply the modification detailed here to the adapter. Note that some earlier adapters do not pass through the outer pins of the game pak connector. It is impossible to use the Super Game Boy at all with such an adapter; buy a newer one. Revision History ---------------- 0.5 · Added pointer to web page containing links to some pictures of the Tri- Star internals · Mention about "discharging" the unit before opening it up. · Added cautionary notes in the Performing the Modification section. · Reversed order of Revision History section · Other minor changes. 0.4 · Added information about universal adapters. 0.3 · Added information about backup devices; apparently these have the same problem as the Tri-Star and Super 8. Other minor changes. [No history maintained for revisions 0.1 and 0.2.] Background ---------- Inside the Tri-Star, one of the lines leading from the SNES game pak connector has a gap in it. This line is for one of the pins on the small outer parts of the connector. [Most SNES games only use the centre portion. The Super Game Boy and Super FX games, e.g. Starfox/Star Wing, use the outer parts too.] It is this unconnected pin which causes the Super Game Boy problem. There may also be problems when using Super FX games via the Tri-Star, but I have not tested this -- after the modification, Star Fox works fine, at least. I did not test any Super FX games prior to performing the modification. The reason why the Tri-Star manufacturer did this is quite complex. I will explain it here, but you may want to skip to the next section ("How the Modification Works"). The Tri-Star is manufactured somewhere in Asia, and is sold in many countries which use the PAL TV system (in fact, the Tri-Star is available on both PAL and NTSC models). It is common for NTSC Super Famicom consoles to be modified for use in Asian countries which use the PAL TV system. Typically, the console is supplied with a so-called "PAL booster", which plugs into the SNES multi-out port. The booster contains a video encoder IC, 4.43MHz oscillator and a PAL RF modulator. It takes the RGB and sync signals from the multi-out port, and encodes them into a PAL composite video signal. There is a multi-out port on the back of the booster into which you can plug an A/V lead. The NTSC composite video signal which is output by the console is replaced with the PAL signal generated inside the booster. A PAL RF signal is available on the booster too, to allow connection to any PAL TV. Some PAL TVs cannot handle a 60Hz display, as output by the Super Famicom. So some way had to be found to make the console output a 50Hz display, whilst maintaining full compatibility with Super Famicom software. This internal modification to the console would usually done before sale: · The S-video luma and chroma lines to the multi-out connector are cut on the console PCB. So there are now two "spare" pins on the multi-out connector -- and you can therefore no longer use an S-video lead to connect your SNES to a TV. · Wires are soldered from the two "spare" pins of the console's multi-out port to two places on the main PCB which relate to the SNES' clock signal. · There is circuitry in the PAL booster which, by manipulating the two pins which are now connected to the clock circuitry, can halt the console for the right amount of time in each frame, to achieve a 50Hz display. Whilst the console is halted, the display is blank; thus there are black borders at the top and bottom of the picture in 50Hz mode. Because the console is completely halted for this "extra" time, it remains compatible with (all?) NTSC software, unlike a real PAL SNES. One of the places on the PCB to which a wire is connected for this is pin 1 of the game pak connector. This is the pin which the Tri-Star does not connect! This was probably done, because the way that the PAL booster alters the signal at pin 1 can interfere with some game cartridges (most probably Super FX games). However, the Super Game Boy needs this clock signal -- it does not work properly without it. All this is irrelevant for the vast majority of SNES users. You just need to know that the problem can be fixed easily. How the Modification Works -------------------------- All that needs to be done is to re-connect the "broken" line. Then the Super Game Boy works as it should. Performing the Modification --------------------------- Whilst the modification is very simple, if you have not used a soldering iron before I suggest that you ask someone who has some experience with soldering and electronics in general to help you. Maybe your local TV repair person will be willing to do it for you, if you provide a copy of this document. Game consoles, in common with most modern electronic devices are VERY SENSITIVE TO STATIC ELECTRICITY. Ideally, wear a grounding strap and work on a conductive surface when modifying your console. Avoid wearing clothes containing man-made fibres, which are prone to static (e.g. nylon). As far as possible, avoid touching component leads or PCB tracks. Handle the board by its edges. There are several pictures of the inside of the Tri-Star which you may want to view before going any further. They are accessible from my web page, the URL of which is given above. You will need the following: · A crosshead screwdriver suitable for opening the Tri-Star case; · A pin, needle, razor blade or similar sharp implement; · A soldering iron and solder, and optionally a short length of bare, uninsulated wire (1cm is enough) and a pair of metal tweezers. Here are step-by-step instructions: 1. With the Tri-Star still connected to the console, remove the AC adapter and all other leads from the console. Turn the Power switch on for a few seconds, and then off again. You may see the console's power LED light momentarily. Doing this dissipates any stored charge inside the Tri-Star. IT IS VERY IMPORTANT THAT YOU DO THIS! 2. Remove the Tri-Star from the console, unscrew the four screws from the underside and lift off the upper part of the case. 3. Remove the Tri-Star PCB from the lower part of the case. It's a tight fit, so be careful. It will help to gently push the edge connector that mates with the SNES' game pak connector up when removing the PCB. 4. Orient the PCB so that the RF modulator is to the right, facing away from you (as if looking towards the front of the Tri-Star when plugged into the SNES). The RF modulator is the silver-coloured metal box at one corner of the main PCB. The PCB which plugs into the SNES game pak connector should be nearer to you. It is perpendicular to the main board. The tracks on this go straight up from the SNES connector end to the main PCB. If you examine the leftmost track, you should see that there is a break in it. This needs to be re-connected. 5. Using a pin, needle, razor blade or similar, carefully scratch away the green material covering the metal of the broken track, on either side of the break. A couple of millimetres on either side should be sufficient. Make sure that you expose all the metal in this area, and wipe off any green dust that remains. 6. Now you need to bridge the gap. There are two ways to do this. The first is simpler, but you may find it trickier to do. Just use the soldering iron and solder to tin the exposed metal on either side of the break (i.e., cover it with solder). Then put enough solder on so that a single blob sticks to both sides of the break, making a connection. The solder tends to move towards the exposed metal and not bridge the gap, however. If you have trouble doing this, you can use the small length of wire, soldering an end to each side of the gap. Hold the length of wire in place with a pair of tweezers while you solder it. 7. That's it! If you have a multimeter, you can check the resistance of the newly-bridged track; it should be near zero. Put the Tri-Star back together, ensuring that the PCB is properly seated in the case before replacing the lid. 8. Connect the Tri-Star to your SNES, and plug the Super Game Boy (and Game Boy game) into the Tri-Star. Switch on, and the Super Game Boy should play properly. ---