[Coco] Kip's Single Board Computer

[Barry Nelson]

 Did you say breadboard? As in the plastic boards with metal strips that act as connectors? Just FYI, I recently had an interesting experience with a breadboard circuit. I had plugged an audio out lead into the wrong row, but I still got audio, but at a low volume, even though it wasn't connected. It turns out there was enough capacitance between the metal strips in the breadboard to pass the audio through as a capacitor. I shudder to think what this might do to a sensitive oscillator running in the multiple megahertz range… Maybe try plugging the cpu into a socket and lifting pins 38 and 39 of the socket so they do not connect to the breadboard, and then connecting your crystal or oscillator to that?

On Sep 19, 2015, at 1:09 PM, coco-request at maltedmedia.com wrote:

> Date: Sat, 19 Sep 2015 10:46:17 -0500
> From: RETRO Innovations <go4retro at go4retro.com>
> To: CoCoList for Color Computer Enthusiasts <coco at maltedmedia.com>
> Subject: Re: [Coco] Kip's Single Board Computer
> Message-ID: <55FD8349.9060500 at go4retro.com>
> Content-Type: text/plain; charset=utf-8; format=flowed
> 
> On 9/19/2015 3:09 AM, Neal Crook wrote:
>> Jim,
>> When you tried the 8MHz oscillator can on extal, with xtal floating (per
>> the data sheet) did you see xtal oscillate as a result?
> I did try that, to no avail, but have not tried it with the SuperPET 6809.
>> 
>> The hitachi datasheet certainly indicates that care is needed on the
>> physical layout to get the xtal to oscillate, but the canned oscillator
>> should be foolproof.
> I agee, which is why I think my "breadboard" setup is wrong, but not 
> sure where I'm going wrong.  I bring upZ80s and 6502 and AVRs all the 
> time no problem, so I'm not completely inept at this.
> 
> It's possible I've fried my 6309 CPU, but it seems strange I've toasted 
> both of them.
> 
> Jim