RK11-C indicator panel inlays?

Todd Goodman tsg at bonedaddy.net
Tue Dec 7 05:27:15 CST 2021


I've used PCBCart.com to have thousands of boards produced. Mostly with 
gold fingers

They've done a good job with the boards, though they're mostly two-layer 
and not overly complicated.

You just tell them how many gold fingers you want (and if you get it 
wrong, their design check will clarify with you).

You also can specify if you want a chamfer on the edge and the degree of 
that chamfer

Things weren't good when the tariffs were in effect and the shippers 
didn't understand what the PCB tariffs applied to and what they didn't.  
That added a lot to the cost.

That's back to normal now but prices are up (like everything else).

Todd

On 12/6/2021 5:45 PM, Mike Katz via cctalk wrote:
> One of my zillions of projects is to redesign Oscar Vermilion's 
> PdDP-8/I using the Raspberry Pi Pico board and these LEDs.
>
> I would use one core for SIMH (the PDP-8 simulator) and one core for 
> the Incandescent Emulation.
>
> Right now I'm too busy finding parts for my real PDP-8/E and getting 
> it running.
>
> Think of the addressable LEDs and LEDs with the shift register built 
> in 😄.
>
> When you are ready for a redesign, you might consider it for a cost 
> reduction.
>
> If I may8 ask a question.  I have never had boards made before. How do 
> I find a good board house that is reasonable and how do I specify the 
> board especially for the PDP-8 Omnibus which should have gold fingers 
> on the edge connectors?
>
> Thanks and good luck,
>
>                   Mike
>
> On 12/6/2021 2:07 PM, David Bridgham via cctalk wrote:
>> On 12/6/21 10:36 AM, Mike Katz via cctalk wrote:
>>
>>
>>> Each LED requires 24 bits of data.  That would be 3,456 bits.  The
>>> WS2812B has a 300uS low start indication and 1.25 uS per bit. That
>>> would mean it would take. 4.62mS to update the all of the LEDs.
>>
>> If I'd known about those when I designed my boards, I might well have
>> gone that way.  They're surprisingly inexpensive even.
>>
>> Instead, I ended up using a 16-LED driver chip that basically looks like
>> a shift-register.  I clock in the 144 bits (just on-off, no fancy
>> tri-color LEDs I'm afraid), toggle the latch signal, and there it is.
>> If you want to support more indicator panels, it's just a longer shift
>> register.  I then added RS422 driver chips for noise immunity and there
>> I was.
>>
>> Dave
>>
>>
>


More information about the cctech mailing list