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By: Anonymous: Neil () on Saturday, March 27 2010 @ 07:29 PM PDT (Read 14437 times)  
Anonymous: Neil

Hi Windell,
Greetings from Australia! I have just assembled my Chronodot Bulbdial, and everything went together well. (Unfortunately the power supply does not fit into our wall sockets, but I have been able to improvise for the moment.) Everything seems to work OK when powered from the power pack, but nothing happens when I connect it to a powered USB hub on my Mac.

I have installed the jumper between Vcc2 and USB5V, and removed the plugpack before connecting to the USB. I checked the soldered joints, and nothing seems to be amiss...

Any suggestions?

Thanks,

Neil





       
   
By: Windell (offline) on Sunday, March 28 2010 @ 02:29 AM PDT  
Windell

Well, that's odd indeed. Have you tried connecting right to the Mac? I wonder if it's an issue with the hub.

* Also, sure that you've connected the USB-TTL connector with the correct orientation?

* A long shot, but if you got the cable somewhere else, you should be aware that there is also a 3.3 V version of the cable that will not work to power the clock

* And most obviously, a flaky solder connection at the connector can cause this very obviously.


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By: Anonymous: Neil () on Monday, March 29 2010 @ 04:53 AM PDT  
Anonymous: Neil

Hi Windell,
Firstly, thanks for the quick response, and sorry for not thinking it through first - it is pretty obvious when you think of it. It must be because I am a mechanical engineer, and hence a bit thick when it comes to electronics.

Anyway, I had a look at the schematics and performed some tests:

I powered the Bulbdial from the plug pack, and measured 5V between pins 1 (black) & 3 and 2 & 3 on the USB port. This shows that the solder joints are OK.

I plugged the USB cable into a powered hub and measured 5V between pins 1 & 2 and 0V between 1 & 3 and 2 & 3. This shows that the cable is no good.

The cable is the one supplied with the kit. The order of the colours is 1 black, 2 brown, 3 red, 4 orange, 5 yellow and 6 green. Is that as it should be? Is it easy to swap them without destroying the sockets? It would be a hassle to have to return it.

Thanks,

Neil





       
   
By: Anonymous: Neil () on Monday, March 29 2010 @ 04:57 AM PDT  
Anonymous: Neil

Sorry, I should have said, the cable supplied is Part # TTL-232R-5V





       
   
By: Windell (offline) on Monday, March 29 2010 @ 05:05 AM PDT  
Windell

>This shows that the solder joints are OK.

Yes, that's a good and clever test.

>This shows that the cable is no good.

No, that doesn't. From what you've described, it still sounds like this could be an issue with the hub, rather than the cable.

Again, have you tried connecting directly to the computer?


> The order of the colours is [...]

You should plug it in with the orientation shown on page 66 of the instruction manual. I've not heard of a case where they were rearranged.



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By: Anonymous: Neil () on Monday, March 29 2010 @ 05:29 AM PDT  
Anonymous: Neil

I have tried connecting directly to the computer as per the manual - No response.

I still measure 0V between pins 1 & 3 when the cable is plugged directly into the computer and even my iPod charger (but not the bulbdial). Should I not be seeing 5V?





       
   
By: Windell (offline) on Monday, March 29 2010 @ 05:38 AM PDT  
Windell

>I have tried connecting directly to the computer as per the manual - No response.

By "No response," do you mean that you can't see 5 V on the cable, or something else? Is the cable working otherwise?

>I still measure 0V between pins 1 & 3 when the cable is plugged directly into the computer
>and even my iPod charger (but not the bulbdial). Should I not be seeing 5V?

I'm really not sure what you're saying here-- you've found a way to connect the USB-TTL cable to an iPod charger? The cable should be capable of providing 5 V from your computer to the Bulbdial.


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By: Anonymous: Neil () on Monday, March 29 2010 @ 12:28 PM PDT  
Anonymous: Neil

No response = no action from the Bulbdial.

I tried conecting the cable to a number of USB sources - computer, hub and iPod charger. In each case, when the header is not connected to the Bulbdial, there is 0V between pins 1 & 3.

When I connect the header to the Bulbdial, there is 3.7V between pins 1 & 3.





       
   
By: Windell (offline) on Monday, March 29 2010 @ 01:01 PM PDT  
Windell

Please be patient with me; I'm *really trying* understand what you're saying.

>No response = no action from the Bulbdial.

Again, by "no action" and "no response," are you referring to (A) powering the clock or (Cool programming the clock?


>when the header is not connected to the Bulbdial, there is 0V between pins 1 & 3.

>When I connect the header to the Bulbdial, there is 3.7V between pins 1 & 3.


Since you refer to connecting the header to the Bulbdial, I'm guessing that when you say "header" here, you actually mean the 6-pin female connector at the end of the USB-TTL cable, NOT the 6-pin right-angle header on the Bulbdial circuit board, and that the voltages that you are reporting are measured on the cable end, not at the header. If this is not the case, you'll need to clarify.

Let's see if I have this right: You are measuring the voltage of the pins on the USB-TTL cable's connector. When it's not plugged into the Bulbdial clock, there is no voltage on the connector output. When it is plugged in, you measure 3.7 V on the connector, regardless of what device it's plugged into on the other side. Is this right?

If that's the case, it sounds more like the cable is getting power from or through the Bulbdial.
- Do you still see voltage when the cable isn't plugged in on the other end?
- Do you see any voltage on the other pins of the 6-pin right-angle header?
- Is that 3.7 V figure independent of what device it's plugged into?

Edit: I had asked what kind of computer-- but you said that it's a mac. Your USB output voltage should be sane directly from the computer.

Finally, what kind of an iPod charger is it? Many iPod chargers put out *much higher* voltage than 5 V; you should check the output voltage to make sure that it's sane.


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By: Anonymous: Neil () on Monday, March 29 2010 @ 02:47 PM PDT  
Anonymous: Neil

Please be patient with me; I'm *really trying* understand what you're saying.


No problems - it's all part of the fun of the hobby. Thanks for all of the help

Again, by "no action" and "no response," are you referring to (A) powering the clock or (Cool programming the clock?

The Bulbdial does not power up. I have not tried any programming yet.

when you say "header" here, you actually mean the 6-pin female connector at the end of the USB-TTL cable

Yes

Let's see if I have this right: You are measuring the voltage of the pins on the USB-TTL cable's connector. When it's not plugged into the Bulbdial clock, there is no voltage on the connector output. When it is plugged in, you measure 3.7 V on the connector, regardless of what device it's plugged into on the other side. Is this right?

Yes

If that's the case, it sounds more like the cable is getting power from or through the Bulbdial.

There is no other power source, except the Chronodot battery.

- Do you still see voltage when the cable isn't plugged in on the other end?
- Do you see any voltage on the other pins of the 6-pin right-angle header?

I am at work at the moment - I'll check tonight.


- Is that 3.7 V figure independent of what device it's plugged into?

Yes

Finally, what kind of an iPod charger is it? Many iPod chargers put out *much higher* voltage than 5 V; you should check the output voltage to make sure that it's sane.

It's a genuine Apple charger. I'll have to check it's voltage. What is the acceptable range?





       
   
By: Anonymous: Neil () on Tuesday, March 30 2010 @ 12:32 AM PDT  
Anonymous: Neil

- Do you still see voltage when the cable isn't plugged in on the other end?

No

- Do you see any voltage on the other pins of the 6-pin right-angle header?


Pin 1 = Black = Earth
Pin 2: 0V
Pin 3: 3.3V
Pin 4: 4V
Pin 5: 3.7V
Pin 6: 5.2V





       
   
By: Windell (offline) on Tuesday, March 30 2010 @ 01:43 AM PDT  
Windell

Okay, I can begin to see some of what's going on here.

It sounds like the cable is *mostly* operating normally, with the exception of the 5 V output line. The 5 V signal on pin 6 is feeding back, though the 10 k resistor on the Bulbdial PCB, to give you that apparent 3.7 V signal on the 5 V input line.

It could be the case that the 5 V wire is broken-- near the 6-pin connector, or that there's something else wrong with the cable, or it was damaged somehow. Please carefully inspect to see if any of the wires there look loose.


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By: Anonymous: Neil () on Tuesday, March 30 2010 @ 04:01 AM PDT  
Anonymous: Neil

The cable looks fine, no sign of damage anywhere.

(Are you really up and about and solving problems at 1:43 am? That's dedication!)





       
   
By: Windell (offline) on Tuesday, March 30 2010 @ 04:51 AM PDT  
Windell

Quote by: Neil

The cable looks fine, no sign of damage anywhere.


Well, I'm afraid that it's probably just a bad one from the factory then... or you managed to break it somehow, but I don't see that you've done anything obviously wrong. It's unfortunate in any case.

A couple of options for you then:

1) It sounds like your cable may be working okay for programming, just not for powering the clock. You could test this and see if that's the case, and just use that cable if you want to reprogram it. For power, you could hack together a cable in about five minutes that just breaks out the 5 V from a regular A-B cable, and use that to run the clock.

2) Contact our web store for a replacement.

>(Are you really up and about and solving problems at 1:43 am? That's dedication!)

Hmm. I thought that 5:38 AM yesterday was more impressive. Confused


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By: Anonymous: Neil () on Wednesday, March 31 2010 @ 03:12 AM PDT  
Anonymous: Neil

Thanks for all the help Windell. I'll see about a replacement from the web store.

Hmm. I thought that 5:38 AM yesterday was more impressive.

Remember I'm in Australia - that's only 11:30 PM.

Cheers,

Neil





       
   



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