Started by Rob Blessin Black Hole, May 08, 2014, 08:23:08 am
Quote from: "barcher174"I'm just going to let these speak for themselves....https://www.dropbox.com/s/6cpz880uc5omshy/IMG_0574.jpghttps://www.dropbox.com/s/0bquepf1h02u26n/IMG_0575.JPGYES. That is an ADB soundboard working with a non-ADB keyboard and mouse. We have a solution. I'll work on a formal write-up with some pics and do a bit more testing to be sure it's stable.So to sum up:1) Machines that currently use ADB sound boxes -do not- need the soundbox to function. If you can live without sound you can hook an ADB keyboard directly to pin 7 of the 19 pin connector.2) If you have an ADB sound board it can be converted to non-adb by cutting a couple traces and adding some passive components. 3) I really need to sleep more. In addition, regarding the power supply, I highly recommend that the 152 not be modified. I do not believe it is safe to operate without the minimum load. There are 2 options. Create a load on the -12V rail, like I have shown with either a fan or a bulb, or you can also source an appropriately sized 1U ATX power supply and modify it using the instructions I have provided. --Brian
Quote from: "barcher174"Hi Rob,I think it would be possible to create a switched approach to this mod. If you put a switch between "pin 2" on the ASIC and ground the soundbox should operate at 72hz again. Also you would want to leave the ADB trace in place. Other speakers will work with the board without a problem. Just try to match the impedance of the existing one. For the power supply you want to pull the load from the output side. This means 12V DC power. Probably a cool thing to do would be to find a router with the right power threshold and make a cube add-on card out of it.
4 3 2 1 28 27 26 _________________ / | 5 | | 25 6 | | 24 7 | | 23 8 | | 22 9 | | 2110 | | 2011 | | 19 +--------------------------------+ 12 13 14 15 16 17 18 1 sound in data 2 sound in sync 3 reset 4 power +5V 5 ground 6 5MHz clock 7 5MHz serial in 8 5MHz serial out 9 keyboard out10 keyboard in11 ground12 power +5v13 ? 14 ? DAC data15 ? DAC clock16 ? DAC select17 oscillator18 power +5v19 ground20 mute 21 volume control ?22 volume data23 volume clock24 ?25 ground26 power +5v27 ?28 sound clock
Quote from: "barcher174"Yes, I think between you and Rob we have more ADB sound boards than next enthusiasts at the moment. I'm thinking maybe a 3D printable enclosure that would have VGA and a switch between ADB and non-ADB would be cool. I've been working on this for a good long while so I'm really happy to finally have results. --Brian
Quote from: "barcher174"I did a test fit inside a sound box today. First image shows how I installed the keyboard connector upside down. I put electrical tape underneath to insulate the previous connections and then glued the connector in place.https://www.dropbox.com/s/h8p3w46wetr68ge/IMG_0582.JPGAnd here it is in a sound box:https://www.dropbox.com/s/vv94y2s6al06ydc/IMG_0581.JPGHere I've annotated the connections on an unmodified board:https://www.dropbox.com/s/tchizz8d1kvoxnk/IMG_0588.JPGA closer look at the ASIC:Unmodified:https://www.dropbox.com/s/eajs0jlpbdzg6bq/IMG_0585.JPGModified:https://www.dropbox.com/s/zijahhjo7hvgq5u/IMG_0584.JPG--Brian
Quote from: "barcher174"Hi All,Good news. Since I have additional boards coming in the mail I decided to experiment on my personal ADB soundbox. Non-ADB and ADB can live happily together in a single sound box. No switch necessary. Just wire the signals as I've already shown and leave the ADB connection uncut. You will of course need to cut a hole in the enclosure to support a second connection, but there is plenty of room inside. Seems like we've got this one solved. --Brian