Tommy's jp1.x vs serial port suggestions

Post by **ElizabethD** » Mon Aug 06, 2007 6:03 pm

A while back, less than a month ago, Tommy put a post about voltages on the serial port for people who use jp1.x remotes. While I don't have any of those, I found the post interesting. Tommy threatened to pull it out if no response. Well, I think he did or I need new glasses. ANy chance it could be recovered and added to one of his stickies about 1.x? I think in the long run the post should be here as a reference.

Post by **vickyg2003** » Mon Aug 06, 2007 6:35 pm

I agree. I've been trying to figure out how to use the voltmeter that I found in the garage. If it is delicate enough for electronic equipment. I'm really afraid of this kind of stuff.

Post by **ElizabethD** » Mon Aug 06, 2007 8:36 pm

You afraid?!?! didn't you solder a bunch of eeproms or something? that's brave thing to do. I wouldn't stick voltmeter probes into the tight spaces of the port. So what I've been doing (parallel mostly, early on when jp1 wasn't working on the laptop too well) is borrow a gadget from the office called BlackBox. You plug, say, serial port into it and then with little leads you work in wider spaces you go connecting things, watch LEDs, and measure what's needed. I used didgital voltmeter from the office. pretty rugged thing. The ancient Heathkit tube-type my husband used to use is shot I think. That one was delicate, or so I was told.

How to use? they have a scale. So you start with 500 volts and go down the scale

actually in computers starting around 5 will do the job. And you use the red and black probes. I think red is positive, but if the needle goes the wrong way then it's negative

That's the extent of my knowledge.

Tommy Tyler · Post by **Tommy Tyler** » Tue Aug 07, 2007 6:05 am

After over 80 hits without anyone confirming they had the described problem, I pulled the Sticky. I have to assume (or hope?) I have the only PC in the universe that behaves like this.

The post on Everything You Need to Know About Testing a JP1.x Interface
https://www.hifi-remote.com/forums/viewtopic.php?t=7987 has been upgraded to add an entire Section 5 describing the problem.

Tommy

Post by **vickyg2003** » Tue Aug 07, 2007 6:28 am

Its not that you are the only one that has the problem, its that you're the only one that has the problem AND UNDERSTANDS it. I think I have the problem, but I'm going through a USB to Serial adapter, which may bring its own set of issues. My remote often freezes after its been connected to IR. My remote often downloads with the signature reverted. I hadn't connected the two until I read the post. I haven't had it happen since reading your post. Its a "sometimes" thing, and I can't get it to happen on a regular basis, to confirm the signature change and key freeze together. Since I am still in the heavy testing phase, I connect the JP1.2 remotes all the time. It only happens every so often. Before I read your post, I was sure it was an extender error, now I'm not so sure. The post helped me a great deal even though I'm afraid to do the probing myself.

Post by **vickyg2003** » Tue Aug 07, 2007 9:34 am

ElizabethD wrote:You afraid?!?! didn't you solder a bunch of eeproms or something? that's brave thing to do.

Yes that was brave on my part, because I AM afraid. My fear limit is about $25 though. I'll poke around on a remote, but when it comes to poking equipment that I'm not sure how to use, into holes on the new lap top I'm not that brave!