Every once in a while I have a problem with my Hydra. I go to download a program using the Propeller tool and I get a message saying it can't find a Propeller chip. The USB port is connected correctly and Windows sees the USB serial port and has the correct driver installed. It's just that the Propeller tool doesn't see the chip. I've tried rebooting Windows, power cycling the Hydra, unplugging and replugging the USB cable and nothing seems to work. The odd thing is that eventually it starts working again later that day or another day. It's just that I haven't been able to find a way to make it start working again. It just starts again by magic I guess. I don't see this same behavior if I connect another board with a Propeller chip like the Chameleon PIC. It just happens with the Hydra. So far, this has happened to me at least three times and it's very frustrating that I have to suspend all of my programming activities and hope that it comes back to life again. Has anyone seen this sort of behavior? Do you know of a reliable way to get the Hydra out of this state?

For what it's worth, I'm using Windows 7 64 bit at the moment but this happened back when I first got the Hydra and was using Windows XP Professional 32 bit so I don't think it has anything to do with the version of Windows.

Another thing --

1. REmove the Prop and re-seat it really good, if you have some contact cleaner use it.
2. Remove the XTAL and re-seat it and / or replace with another XTAL.
3. Replace the USB cable itself.

Andre'

Thanks for all of the suggestions. Unfortunately, none of them worked. I guess I'll have to wait until the Propeller gods decide that it is time for my Propeller chip to be resurrected. Actually, I have another chip. Maybe I should try swapping out the Propeller for another one...

Give it a try, also, you might just try re-flowing the Propeller socket (without the chip in it). Also, UNINSTALLING the FTDI drivers and re-installing them.

It's weird its doing on the HYDRA, there is obviously something funky, another thing try pulling any cards plugged in, and or use the 128K expansion module that comes with it, and work with that plugged in, see if it has the same problem with a card in using external memory.

Andre'

Well, I did nothing and today the Hydra seems to be working. Frustrating! I'll try swapping the Propeller chip to see if that makes it more reliable once I find my spare in a very disorganized "box of parts"!

I found my spare Propeller chip but I have another question. Are there any known problems with earlier Propeller chips? The one I was going to swap into my Hydra is fairly old from back when Parallax charged $12.95 each for the PDIP version. I also have some newer PDIP chips that I ordered within the last month. Are there any known differences or problems with older chips or are they all interchangeable?

Well, the early ones had more issues and failed more, but the design is the same, so just plug them in, they are the same. Newer ones might be able to go a little faster with over clocking.

Andre'

Okay, I guess I'll wait until my Hydra fails again and then try swapping out the Propeller chip. Do you have any idea if any of the problems with the early chips had anything to do with download connections?

My Hydra failed to connect again this morning so I swapped out the Propeller chip. It seems to be working again but we'll see how long that lasts.

Interesting, sounds like it needs to be reflowed, you might just have a shitty solder joint on the USB connector, or some of the wires thereof, if you have a needle point iron, you might try putting a ton of flux on the USB connector and reflowing the pins and see if that helps.

Andre'

But Windows sees the USB serial port even when the Propeller Tool can't connect. That's why I figured it must be something beyond the USB connector and circuitry (like the Prop chip).

Well, yes and no, sometimes, it can be an intermittent connection, or the ground is bad, etc. so the initial signaling works then it fails as static charge grows, or this or that, so can't hurt to try that as well --

Andre'

Okay, I'll try that if I have to. So far I've been trying to avoid taking a hot soldering iron to my beautiful Hydra board!

well, some magnifying glasses, a steady hand, hold your breath, and a lot of flux to reflow those connections, will go pretty easy then clean with flux remover/alcohol.

Andre'

I know this is an old thread but I have had the same problem with my Hydra. The reason in my case was obvious; the cable got snagged and pulled too hard on the mini usb socket and damaged the pins. I am reluctant to try to replace the socket since I am not very experienced with SMT soldering. I ordered a USB2SER adapter from Parallax and hope that will let me continue to use the Hydra through the serial to usb port that Andre left on the board. I have looked around just for a replacement Hydra board and can only find the full developement kit. I am looking forward to the Hydra 2 and think I will also try to get one of the XGS systems. Can the XGS systems work with Hydra Net? I wanted to fool around with that but only have the one board. Also in general I found that having a Parallax Quickstart lying around is great for figuring out where the problem lies in troubleshooting Hydra questions.

Email parallax and tell them the header is bad, see if they will replace the board (you send them yours, they send you a new one).

The hydra net is nothing more than a pair of serial lines with some clever loading to minimize reflections, etc. So, all you need is any other microcontroller board, a few IO pins, then mimic the HYDRA net resistors and caps on the other end and then bit bang over 100-300 feet, should work fine.

Andre'