Super NES/Super Famicom 50/60Hz Switch Modification =================================================== (rev. 0.4 25-Jan-98) This document is copyright © 1997-1998 by Mark Knibbs . The latest version, and several other console-related documents, should be available from my web page: http://www.netcomuk.co.uk/~markk/index.html Repris par FFVIMan: http://www.switch-snes.com The direct URL for this file is: http://www.netcomuk.co.uk/~markk/Consoles/SNES_50-60Hz_Switch.txt 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. Please contact me if you have any comments, suggestions or questions about this document. Revision History ---------------- 0.1 21-Dec-97 First release. 0.2 26-Dec-97 Added note about static electricity. Emphasised necessity of dissipating stored charge before opening console. Other minor changes. 0.3 27-Dec-97 Minor changes. 0.4 25-Jan-98 Added that you should connect a 2.2kOhm resistor between the regulator Vcc terminal and the switch. Added pointer to digitised pictures of a modified console. Introduction ------------ This document describes how to add a switch to your Super NES or Super Famicom video game console in order to switch between 50Hz (PAL line standard) and 60Hz (NTSC line standard) display modes. Why might you want to do this? Well, I can think of several reasons: · If you own a PAL Super NES, you will be familiar with the horrible squashed picture and 17%-too-slow gameplay. Almost all games work fine in 60Hz mode, and thus you can play them how the designers intended; full-screen and at full speed. · Most later Super NES games contain code that checks for a 50Hz or 60Hz display, and refuses to work if it find the "wrong" one. For example, the US version of "Super Mario All-Stars" refuses to work on a PAL SNES, and PAL Super Metroid refuses to work on an NTSC SNES. By fitting a switch and setting the correct mode, you can play games like this. Since most games only do the check right at the start, you can switch to 60Hz mode when playing the game. This allows most PAL games to be played full-screen. · Users of NTSC consoles can see exactly how awful the PAL versions of consoles and games released in Europe really are. · NTSC users who find a game particularly difficult or too fast can slow it down to the more sedate PAL speed. Background ---------- Japan and North America are the two main markets for game consoles. Both Japan and the USA/Canada use the NTSC television system. Consoles designed to be played on NTSC TVs show 60 frames (60Hz) per second, each consisting of 262 lines. Europe, Australia and Hong Kong are other markets for game consoles. However, the TV standards used in these countries, PAL and SECAM, show 50 frames per second (50Hz), each consisting of 312 lines. When the console manufacturer gets around to adapting their console for these markets, they usually go the easiest and cheapest route. In order to be compatible with all TVs, they make the PAL version of the console always output a 50Hz picture with 312 lines. This is where the problems occur. PAL consoles show 50 frames per second, as opposed to 60 for NTSC consoles. This means that the gameplay is slowed down by 16 2/3%, or put another way it should be 20% faster than it is. Unless the game code is adjusted to take account of this (and this is seldom done), PAL gamers are stuck with too-slow gameplay. Another problem results from the different number of lines in the TV picture. Rather than modifying the game console and programs to use the extra 50 lines in the PAL standard, the console is made so that there are large black borders at the top and bottom of the screen. It is rather like watching a "widescreen" film, except the picture is squashed vertically leaving the black borders. This squashing is most noticeable on games which use large circular shapes. Also, some games have small borders even on NTSC consoles. On PAL consoles, these borders become very large indeed. These two problems mean that playing games on a PAL console is nowhere near as fun as it should be. The annoying thing is that it would be so easy, and cheap, for the console manufacturer to avoid them, as this modification demonstrates. Most modern TV sets can accept a signal at either 50Hz or 60Hz, automatically sizing the picture so that the image fills the whole screen. However some older sets apparently have problems with this. For example, an old European TV may show a "rolling" picture when a 60Hz signal is input. If the manufacturer were to simply fit a switch allowing the user to choose between 50Hz and 60Hz modes, most people could play games full-screen, at the correct speed. Those with incompatible TVs could still play in 50Hz mode. Since Nintendo did not bother to fit such a switch, you must fit one yourself, and that is what this document is about. Note that the colour standard of the RF and composite video outputs is unaffected by this modification. This means that you will be able to view the 60Hz display on a PAL-only television, and vice versa. The picture output could be called "PAL-60", or "NTSC-50" if you have an NTSC console. Most modern televisions will automatically resize the picture when switching between modes. Some older sets may not like the different frame rate; adjusting the vertical hold control (if present) should solve this. Because of the different lockout chips, to be able to play any PAL games on an NTSC console or vice versa, you need to disable the lockout chip inside your console. It is a good idea to do this at the same time as you add a 50/60Hz switch. For instructions on how to disable the lockout chip, see: http://www.netcomuk.co.uk/~markk/Consoles/SNES_Lockout.txt Alternatively, "universal adapters" are widely available, at least in Europe. These have two connectors. In one you put the foreign game to be played, and in the other a domestic game. The lockout-related lines are routed from the domestic cartridge, thus fooling the console into playing the foreign game. By disabling the lockout chip and fitting a 50/60Hz switch, you should be able to play almost any Super NES or Super Famicom game on your console, regardless of the country of origin. Even counterfeit games which have no lockout chip inside should work. Note that you will need an extension adapter to use US cartridges with a PAL Super NES or Japanese Super Famicom, due to the different shape of cartridge opening used. If you remove the plastic tabs from behind the cartridge slot in a US Super NES, you can play Japanese and PAL games directly. How the Modification Works -------------------------- Inside the Super NES there are two graphics chips, called PPU1 and PPU2; PPU is short for "Picture Processing Unit". These are responsible for creating the Super NES graphics. Back in the days of the 8-bit NES, PAL and NTSC NES consoles used different graphics chips, so it is not possible to fit a 50/60Hz switch to a NES. Luckily Nintendo changed this scheme for the Super NES. Both PAL and NTSC consoles use exactly the same PPU1 and PPU2 chips. Whether the console outputs a 50Hz or 60Hz picture is determined by what voltage a certain pin of each chip is at. The circuit boards of PAL and NTSC consoles differ slightly here. This pin, termed "PALMODE", is held at 0V for NTSC consoles, and +5V for PAL consoles. What the modification does is to disconnect the two PALMODE pins from the circuit board, and wire up a switch so that in one position the PALMODE pins are at 0V (giving a 60Hz display, the default for NTSC consoles), and in the other the PALMODE pins are at +5V (giving a 50Hz display, the default for PAL consoles). You can switch between 50Hz and 60Hz modes at any time, even when the console is on. The procedure given here should work for any Super NES or Super Famicom. However, I have not seen the new model US Super NES. If you fit a switch to one of these, please let me know, and tell me if there are any differences. If you perform this procedure on your console, PLEASE LET ME KNOW WHETHER IT WORKS! I want to update this document so that it's applicable to as many consoles as possible. Please tell me which PCB revision your console has (e.g. SHVC-CPU-01, SNS-CPU-GPM-01) and its serial number. I have successfully carried out this procedure on a U.K. model Super NES, and do not anticipate any problems with performing it on any Super Famicom or Super NES console. Performing the Modification --------------------------- Whilst the modification is fairly simple, if you have not used a soldering iron before I suggest 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, the accompanying picture and a screwdriver for opening the Super NES case. 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. Print out and read this document several times before opening your console. There is a picture to accompany this file; I suggest you view this before opening the console. The URL is: http://www.netcomuk.co.uk/~markk/Consoles/SNES_Switch_Pic.gif There are also some digitised pictures of a modified console. You can find these at: http://www.netcomuk.co.uk/~markk/Consoles/SNES_mod_pics.html You will need the following: · A SPDT (single pole, double throw) toggle switch, of "break-before-make" type. If it isn't of break-before-make type, you will not be able to switch modes with the console powered on. Most or all toggle switches (silver coloured metal lever) are break-before-make. Some slide switches are not. The switch that I used looks something like this (side view): /\ \ \ Switch lever \ \ \ \ _\_\_ __| |__ | | | | Switch body |___________| | | | Switch terminals · Four lengths of thin insulated wire, long enough to reach from the circuit board to outside the case; 30cm should be sufficient. Using a length of ribbon cable is a good idea, as all the wires are together. · A 2.2kOhm (i.e., 2200 ohms) resistor · Some insulating tape is advisable. · A screwdriver suitable for opening the Super NES case. The screws are special tamperproof screws, referred to as "System Zero" or "Line Head System". A suitable screwdriver can be obtained from a company called MCM Electronics in the USA (http://www.mcmelectronics.com/) or from RS Components in the UK. · A crosshead screwdriver suitable for removing some screws inside the Super NES (a "No. 1" bit should be suitable). · A low power grounded soldering iron with a fine bit and some desoldering braid. · A multimeter or continuity checker (useful but not essential). · A thin needle or similar implement. When removing screws, make sure you remember which type goes in which hole! Here are step-by-step instructions: 1. Turn off the console and remove all leads attached to it (AC adapter, controller, A/V lead, etc.). After doing this, turn the power switch on for a couple of seconds and then off again. This dissipates any stored charge inside; you may see the power LED light for a moment as you do this. IT IS *VITALLY IMPORTANT* THAT YOU DO THIS! YOU RISK DAMAGING YOUR CONSOLE OTHERWISE! 2. Turn the console upside-down, and remove the six screws from the base. Turn it back over, and lift off the upper part of the case. Position the console so that it is facing you. 3. Remove the eject lever. Pull up the right-hand side of the metal rod and slide it out, then remove the lever and spring. 4. Remove the two screws which secure the power switch to the casing. Lift up the switch so that you can get at the screw below. 5. Gently remove the ribbon cable which leads to the controller socket PCB from the connector at the front of the PCB. You do not need to do this if you have a late revision console. You can identify this by the fact that there are only two screws holding down the shielding, and you can see that the ribbon cable does not interfere with removal of the shielding. 6. Now unscrew the metal shielding from in front of the cartridge slot. The exact details of this step depend on which revision PCB your console has. I will give specifics for the three variants that are known to me. · For early consoles, which can be identified by the separate plug-in sound module "SHVC-SOUND", there are six screws to remove from the shielding, including the two which are on either side of the cartridge slot. (After removing the shielding, you may see "SHVC-CPU-01" printed on the PCB if you have a U.S. or Japanese console.) · For later consoles, which have no separate sound module, there are four screws to remove. (You may see "SNSP-CPU-02" printed on the PCB after removing the shielding for a PAL console.) · For still later consoles, there are two screws to remove. There is no need to remove the controller ribbon cable. (You may see "SNS-CPU-GPM-01" printed on the PCB after removing the shielding for a U.S. model console.) 7. Carefully lift up the metal shielding. The edges may be quite sharp. You will see various chips. Locate the PPU1 and PPU2 chips. These are two of the largest chips on the board, so you should find them easily. They are in front of the game pak connector. PPU2 is nearest the connector, and PPU1 is in front of PPU2. 8. Now you need to find the PALMODE pin on each of PPU1 and PPU2. In both cases, the PALMODE pin is one of the pins on the left-hand edge (the edge nearest the power switch). There are pin numbers printed on the PCB next to both ends of each edge of the PPU chips. Refer to the accompanying picture. For PPU1, the pin is the seventh along from the one at the end nearest to you. It is pin #24. For PPU2, the pin is the one at the end nearest to you. It is pin #30. 9. Both PALMODE pins need to be removed from the PCB and carefully bent up, so that wires from the switch can be attached to them. Make ABSOLUTELY SURE that you are working with the correct pins! Use the desoldering braid and soldering iron to remove some of the solder from each pin. It may help to cut the end of the braid into a "V" shape, so that you don't inadvertently desolder any adjacent pins. Position the end of the braid over where the pin meets the PCB, and briefly press down on this with the soldering iron bit. You should see that some solder has been "sucked into" the braid. Using the needle, apply a gentle levering action to the pin as you momentarily touch the soldering iron to it. The pin should come away from the PCB. Carefully pull it up using the tip of the needle as a lever, so that the end is a couple of millimetres away from the PCB. When you have done this for both pins, cut a length of insulating tape and lay it on the PCB, to the left of the PPU chips. Doing this will reduce the likelihood of damage occuring when you do the soldering later on. 10. Now is a good time to attach the wires to the switch. I'll assume that you are using a length of ribbon cable with four wires here. Firstly, make sure you have a long enough piece of cable. At least enough to go from the PPU chips to outside the case, with some to spare. Separate the four wires at one end of the ribbon cable, and strip a few millimetres of insulation from each of the four. Twist the ends of the two middle conductors together, and tin all three exposed ends (dip them in a blob of molten solder on the soldering iron). This stops strands coming away from each conductor. Take the SPDT switch and solder the middle two wires of the ribbon cable (which should now be joined together at the end) to the middle terminal of the switch. Solder each of the outer two wires to each of the remaining two switch terminals. Make sure that there are no short circuits. If necessary use some insulating tape or heat-shrink tubing to insulate the switch terminals after soldering the wires. Now decide where you want the switch to go. I suggest passing the ribbon cable through the grille at the back of the case. Doing it this way you do not need to modify the case at all. Tie a loose knot in the cable just inside the case, to prevent damage if someone were to accidentally pull on the switch. Alternatively you could drill a hole in the case, and mount the switch through there. Separate the four wires at the free end of the ribbon cable. 15 or so centimetres should be enough. Strip and tin each end. 11. Locate the 7805 voltage regulator. This is fixed to the left-hand side of the metal heat-sink (the large metal part that lies above the rear half of the PCB). It has three pins, marked I, G and O. You are interested in the G and O pins. G (for ground) is at 0V, and O (for out) is at +5V. G is the middle pin, and O is the pin nearest the front of the console. Solder one of the outer conductors of the ribbon cable to the G pin of the 7805 regulator. It will help if you bend the end of the wire into a small hook shape before doing this. Take the 2.2kOhm resistor, and solder the other outer conductor of the ribbon cable to one end of it. Solder the free end of the resistor to the O pin of the regulator. Use some insulating tape or heat shrink tubing to ensure that there is no possibility of the resistor leads causing a short circuit. Inspect the joints to check that there is no short circuit between the G and O pins. Use a multimeter to check this if necessary. 12. Now you need to solder each of the two middle conductors of the ribbon cable to one of the PALMODE pins which you bent up from the PCB earlier. As with the other wires, it helps to bend the ends into a small hook shape. Make sure that you don't accidentally short out adjacent pins of the PPU chips by e.g. dropping a blob of molten solder on them. It is important that the wires which are now attached to the PPU PALMODE pins do not put any strain on the pins. Arranging them so that there is some slack, you can stick the ribbon cable to a bare spot on the PCB with insulating tape to ensure that the cable cannot move about and thus pull at the pins. 13. Almost there. Check again that you haven't inadvertently created any short circuits during soldering. It is a good idea to test the console before putting it back together. Rest the power switch on its mounting and connect the AC adapter, controller, video lead and a game pak. Switch the console on. If all has gone well, the display should appear, in either 50Hz or 60Hz mode depending on how the switch is set. Flip the switch and notice how the display changes. Play a game and see the speed difference. Turn the console off and remove all attachments (AC adapter, etc.). Turn the power switch on and then off as in step 1. 14. Put the console back together. The procedure is the reverse of steps 2 to 7 above. You may find fitting the eject lever tricky. If so, put the metal rod through the lever, and put the spring on the left end of this, so that the outwards-pointing end of the spring is downwards. The outwards-pointing end should be the longer of the two. Ease the spring and lever into position, ensuring that the end of the spring goes into the recess in the casing. Now carefully move the other end of the spring back until it is in the recess in the lever. Credits ------- Thanks to: · Rowan for drawing the original picture that illustrated this modification. · Karel Pauwels for pointing out the need for a resistor between Vcc and the switch. · H. Meun for creating and sending me the digitised pictures of his modified console. --- http://www.ffviman.fr/switch-snes/ [5.7.6]