New ADB Soundbox replacement

Started by barcher174, March 04, 2018, 08:46:41 am

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barcher174

Hi All,

Thought I'd post a little teaser of a project I've been working on. I call it the NoSoundADB board. Basically it's an ADB sound board without the sound.



Keyboard and mouse work perfect. Now I'm focusing on video.

eagle

That's a very neat project.

I think it's exciting to see the new projects going on, from this one to the NeXT-USB adapters.
My NeXTs:
NeXT Computer prototype (68030-25 x2, 68040-25)
Two NeXTstations (68040-25)
All mono

Rob Blessin Black Hole

Hello Brian: Awesome stuff , let me know when they are ready and will there be a non adb version as well? Best Regards Rob Blessin
Rob Blessin President computerpowwow ebay  sales@blackholeinc.com http://www.blackholeinc.com
303-741-9998 Serving the NeXT Community  since 2/9/93

barcher174

I would like to eventually do something similar for the non-ADB, but that will be more complicated. Personally I almost never use sound on my systems anyway. Giving that up simplifies the problem tremendously.

barcher174

Did some additional work tonight. Everything seems to be working now. I'll need a board revision with some fixes.





A couple notes:

1) this device will fail the sound test at boot. This should be disabled in the PROM. This is the default state.

2) The original next straight cables may not have the ADB pin connected. I think all the Y cables are fine. I forgot this and wasted a lot of time....

I'm pretty happy with the results overall.

krazycat

Great project, very useful since the original Soundboxes are so rare. If you produce the NON-ADB version, I would buy two (and two megaloads)  8)

Andreas

this thingy does only work for the mono turbo slab since others doesn't support ADB devices?

barcher174

Quote from: "Andreas"this thingy does only work for the mono turbo slab since others doesn't support ADB devices?


Correct, this requires a turbo system: mono, color, or cube. The video out will not work on a color system.

bobo68

Quote from: "barcher174"I would like to eventually do something similar for the non-ADB, but that will be more complicated. Personally I almost never use sound on my systems anyway. Giving that up simplifies the problem tremendously.


Why is that so? Isn't it just some other pins you need to route from the DB-19 connector to the keyboard output?

barcher174

The non-adb signal needs to be syncronized to monitor clock. I think I recall it working at 5mhz which complicates using a microcontroller.

bobo68

Quote from: "barcher174"The non-adb signal needs to be syncronized to monitor clock. I think I recall it working at 5mhz which complicates using a microcontroller.


You mean one has to pick up the signal from the keyboard and mouse and then sync it with the monitor clock to pass it to the NeXT?

barcher174

Quote from: "bobo68"
Quote from: "barcher174"The non-adb signal needs to be syncronized to monitor clock. I think I recall it working at 5mhz which complicates using a microcontroller.


You mean one has to pick up the signal from the keyboard and mouse and then sync it with the monitor clock to pass it to the NeXT?


I'm hoping that's all there is to it, yes.

Rob Blessin Black Hole

Hello Brian: This is all cool stuff , would it be possible to add something similar to Drak's   USB adaptor ...  obviously the ultimate toggle switch options would be choice of USB or ADB or NON ADB peripherals  to bring sound back in some sort of NeXT PCB sound board emulator  that would plug into your box  USB ?
https://www.mouser.com/ds/2/737/adafruit-proto-shield-arduino-932880.pdf   or check this out https://www.adafruit.com/product/2133   Best regards Rob
Rob Blessin President computerpowwow ebay  sales@blackholeinc.com http://www.blackholeinc.com
303-741-9998 Serving the NeXT Community  since 2/9/93

barcher174

New board came today:



Keyboard and mouse are working well. The video seems a bit fuzzy, but that could be my cable and not the board. I'll need a properly shielded cable to confirm. Either way, the video is probably not very useful anyway.

So where to go from here? Well at this point I'm not going to waste the 19pin connectors on this board. I've gotten quite a bit of encouragement to move on to the non-ADB version. Nothing is wasted because I'll need everything I learned here to continue on. As I stated before, this becomes a software problem as well as a hardware one. In addition the megaload functionality will be integrated into the board as well (that part is easy and already done). No promises on timeline, but I'll try to post updates when it's meaningful.

Andreas

Quote from: "barcher174"Either way, the video is probably not very useful anyway.


As far as i understood, this board makes it possible to power on a Turbo slab and use it with (Apple)? ADB keyb/mouse and VGA video - or not?
So i think the video-out is essential.