TXLog - an Eggfinder accessory

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Flash memory is written in sectors, much like rotating disk memory. Whether you write one byte or 512, you're writing the entire sector. If something interrupts that process, you'll lose the sector. An Eggfinder sends around 100 bytes per second, so you'd potentially lose 4 or 5 seconds, and if that data spans multiple sectors you could potentially lose more. Maybe the card jiggled loose... we recommend that you tape it in with some good masking tape (not the low-tack blue/green stuff).
 
Flash memory is written in sectors, much like rotating disk memory. Whether you write one byte or 512, you're writing the entire sector. If something interrupts that process, you'll lose the sector. An Eggfinder sends around 100 bytes per second, so you'd potentially lose 4 or 5 seconds, and if that data spans multiple sectors you could potentially lose more. Maybe the card jiggled loose... we recommend that you tape it in with some good masking tape (not the low-tack blue/green stuff).

i suspect that the issue was my daughter powered down the entire RX with everything running - Bluetooth and logger. Apparently because I had no labels on the switches she thought she would find out what they do:facepalm:. The PC got upset about it so I gave up on it and thought I'll just fall back on the logger to get data. I think at that stage however the data card was corrupt and not recording anything. But just to be sure my son also decided that he would find out what they do :facepalm::facepalm:. So between them they managed to make the thing unhappy. Fortunately not a critical flight but I'll be making a few adjustments to try and prevent these issues.
 
Just set mine up. However, after running for ~5 minutes, no log file is created. The Eggfinder works (verified I was getting signal on the receiver) and the SD card has a config file, but no log file.

Any ideas?
 
Just set mine up. However, after running for ~5 minutes, no log file is created. The Eggfinder works (verified I was getting signal on the receiver) and the SD card has a config file, but no log file.

Any ideas?

Is the LED on the OpenLog module flashing? It should log entries almost immediately after powering up. It does not need to obtain GPS lock to write to the log.
 
Did you buy the OpenLog module from Cris (Eggfinder)? I tried it with one from Ebay and it didn't work, same problem as you. I think the one bought was set with the wrong bit rate to work with the Eggfinder.

Just set mine up. However, after running for ~5 minutes, no log file is created. The Eggfinder works (verified I was getting signal on the receiver) and the SD card has a config file, but no log file.

Any ideas?
 
Just needed to turn it off and on again a couple times! Chris' instructions indicated there might be an initial setup, but I had already power cycled it once. For whatever reason, one more off and on again did the trick.

The instructions didn't make it quite clear that there were two green LEDs on the underside of the GPS log. Once it was working it was obvious.

It's been fine since then, need to try it a couple more times on flights. First flight I got no data because the card popped out when the rocket tipped over while I was loading it on the pad, and I didn't notice until I got it back. Second one stayed in (tape) but didn't get many good points on the way up (really good data on the walk to the pad and for the last ~20 seconds of descent, but must have partially lost lock or something on the up. Used GPS cockpit to convert and Google Earth to view.
 
Glad to hear it.
Yes, it’s pretty normal to lose lock on the way up. Google earth will plot the launch pad, then the point at which lock is regained, and then the descent. Sometimes you may have some ‘noise’, in the form of invalid coordinates as it’s regaining lock. It’s easy to delete those lines from the text file, giving a much cleaner Google Earth view.
 
Did I read that this will/can work with the Mini as well?


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I guess I was asking if you could just wire an OpenLogger to the Mini. Not necessarily via an adapter or attachment.


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This particular board is sized for the TX B6/B7 versions, but you can connect an Openlog to any of the Eggfinders and the TRS; you just need to solder 3 wires. I'm working on a document for that...

I was referring to this.


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You can connect an OpenLog directly to the programming header on the Eggfinder Mini. Connect the two power pins on the OpenLog to the appropriate power pins on the Mini, and connect the RXD pin to RXD on the OpenLog.
 
You can connect an OpenLog directly to the programming header on the Eggfinder Mini. Connect the two power pins on the OpenLog to the appropriate power pins on the Mini, and connect the RXD pin to RXD on the OpenLog.

Thanks Cris!


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Wired up an OpenLog to a mini with half of a 3 pin cable, (can go to a regular Tx if needed). I also wire jumpered another to my LCD gps to record my wandering around the launch for fun. Now I just need to put some connectors on my TRS. Digging the NMEA converter Kurt posted, makes for a slick Google Earth display.
 
Anyone know where to get a good 3.3v source on the TRS? One of the pgm pins showed 3.3v, but really didn't like running the data logger.
You could get 3.3V directly off the LD1117-33 regulator IC tab and pin 2, or off the 3.3V pgm pin, but check with Cris to confirm this.

You might need to increase the capacity of your battery if the extra load from the additional circuit is significant.
 
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I've connected OpenLog's to TRS's several times... connect it to the RF module. From left to right, Pin 1 is 3.3v, Pin 3 is GND, and Pin 4 is RXD (which you will connect to RXD on your OpenLog). On the next release of the TRS PC boards there will be a place to put the OpenLog header, just like there is on the TX.
 
I've connected OpenLog's to TRS's several times... connect it to the RF module. From left to right, Pin 1 is 3.3v, Pin 3 is GND, and Pin 4 is RXD (which you will connect to RXD on your OpenLog). On the next release of the TRS PC boards there will be a place to put the OpenLog header, just like there is on the TX.
Thanks Cris, exactly what I was hoping for.
 
I've connected OpenLog's to TRS's several times... connect it to the RF module. From left to right, Pin 1 is 3.3v, Pin 3 is GND, and Pin 4 is RXD (which you will connect to RXD on your OpenLog). On the next release of the TRS PC boards there will be a place to put the OpenLog header, just like there is on the TX.
What about on the LCD board? Any plan to incorporate OpenLog support on that?
 
It's already there if you want it... just connect it to the 4-pin Bluetooth header. You'll have the match up the signals... the pinning is for a BT06 Bluetooth module, I think the OpenLog pinning is different.
 
It's already there if you want it... just connect it to the 4-pin Bluetooth header. You'll have the match up the signals... the pinning is for a BT06 Bluetooth module, I think the OpenLog pinning is different.
Cris, I looked on your website for the data logger but couldn't find it. Still selling them? Got a direct link?
 
It's buried in the individual kits and options for the GPS trackers on the "Purchase" page, but yes, we have them. They're $12.
 
It's already there if you want it... just connect it to the 4-pin Bluetooth header. You'll have the match up the signals... the pinning is for a BT06 Bluetooth module, I think the OpenLog pinning is different.

I already have a Bluetooth module connected to my LCD. Is it ok to connect both a Bluetooth module and an Openlog to the LCD or can I only use one at a time?
 
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