Re: Where do I get a POWER OK for Widget?

Thanks James and Jason,

I've successfully powered a working Widget by following your advice. For anyone searching the archives, here is the Widget power connector pinout I used, as you would see if you were looking down onto the top of the Widget and the connector.

           +--------+
     <-----|   -12v | 8
           | No pin | 7
     <-----| Ground | 6
To   <-----|   +12v | 5
PSU  <-----| Ground | 4
           | Pwr OK | 3
     <-----|   +12v | 2
     <-----|    +5v | 1
           +--------+

and as you can see, the Power OK pin is not connected. The connector I used was a Molex 09-50-1081 housing
<https://www.molex.com/molex/products/datasheet.jsp?part=active/0009501081_CRIMP_HOUSINGS.xml>
with 08-70-1030
<https://www.molex.com/molex/products/datasheet.jsp?part=active/0008701030_CRIMP_TERMINALS.xml>
crimp terminals (although Molex would seem to prefer to only sell those as packaged in 08-70-1031 now).

On my working Widget, the Power OK pin was pulled up to +5V as James suspected. On my broken Widget, however, this did not happen. There's +5V on the other side of R1, so something else must be pulling it low. There is not much circuit there to do that, though. Pin 2 of U11 is high; pin 3 is low; no surprises there. This result obtains regardless of whether the controller is plugged into the rest of the Widget.

So, I'll need to figure out what's pulling this line low. It gives me hope that this drive can be resurrected---maybe this is the only problem. Happily, I was able to use my UsbWidEx to test the Widget's servo directly: the drive spins up (with much groaning after 20 years of being idle) and the servo walks along the disk in the ordinary way. That's pretty good news, I should think!

Here's my UsbWidEx->Widget Servo adapter at work: https://photos.app.goo.gl/Xau9VneiGIFBnLB02

Thanks for your help,
--Tom

On Thursday, March 29, 2018 at 12:23:37 AM UTC+1, compu_85 wrote:

>
> I didn't connect that line on the widget I have in an external enclosure 
> and it works fine. 
>
> I've only used it with BLU and Xenix, so there might be a status that the 
> Office System looks at but Xenix ignores. 
>
> On Wed, Mar 28, 2018 at 6:49 PM James MacPhail <g..._at_email.domain.hidden 
> <javascript:>> wrote:
>
>>
>> As far as I can tell:
>>
>> The DataPower power supply does have a "Power OK" signal on pin 21
>> (Labeled "/Power Fail" on the schematic.)
>>
>> You measure +5 on the pin when the Widget is attached because it is
>> pulled up to +5 by R1 on the Widget.
>>
>> You measure 0V on the pin when the Widget is not attached because it
>> is not driven by the power supply (it is an open collector output
>> that can only sink current).
>>
>> This signal doesn't go to the motherboard.
>>
>> I suppose the simplest approach is to leave the pin unconnected and
>> the Widget will pull it high.
>>
>> HTH,
>>
>> James
>>
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>

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