Intermitent Results

Forum for the discussion of JP1 Interfaces, hardware hacks, etc.

Moderator: Moderators

HkyFrk
Posts: 32
Joined: Sat Dec 27, 2003 4:57 pm

Post by HkyFrk »

I have a simple interface that used to work. Now I get " no response from interface". When I take off the cable the led blinks twice. What does this mean????? Help!!!

Thanks
johnsfine
Site Admin
Posts: 4766
Joined: Sun Aug 10, 2003 5:00 pm
Location: Bedford, MA
Contact:

Post by johnsfine »

It is quite common for the led to blink twice when you disconnect the cable.

It normally shows that the reset signal within the JP1 interface is connected properly and that the voltage in the PC parallel port is too low for RESET to work perfectly with your remote. The JP1 interface should work even with the voltage too low for proper operation of the reset signal.

I don't think you get this symptom from plugging the JP1 connector backwards, but I'm not certain, so make sure it is plugged in correctly.

The parallel port voltage might be too low for operation of the other signals in the JP1 interface (though those aren't as picky about voltage as RESET is). In that case it probably would work if you used it without batteries in the remote.

Which resistor values are in your JP1 cable (the old reccomended 10K or the new reccomended 1K)? The lower resistors will make the basic operation of the interface a little less picky about Printer port voltage.
HkyFrk
Posts: 32
Joined: Sat Dec 27, 2003 4:57 pm

Post by HkyFrk »

I am using th 1k resistors and the 1n5818 diode. What I can't understand is that it used to work and now it won't budge. I checked all the connections and they are good.
usblipitor
Posts: 516
Joined: Fri Oct 10, 2003 10:06 pm
Location: Greenbelt, MD

Post by usblipitor »

If you have a parallel port printer somewhere in the basement, dust it off and hook it up to the parallel port and see if the parallel port still works. Maybe something on the parallel port burned out?
Post Reply