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By jremington

Yes, the documentation on the Spark Fun site on how to use OpenLog sucks. To talk to the OpenLog, you have to have another computer running a terminal program, or a microprocessor with a TTL level serial RS232 output port.

If you use a PC, Mac, or Linux, the terminal program has to be connected to the correct COM port. Furthermore, you need a serial adapter connected to the computer so that the RS232 output signals are at the right voltage levels (0 and 5V or 0 and 3.3V) to connect to the OpenLog. FTDI and other companies make USB serial adapters that "look like" a serial COM port to the computer.

It sounds like you already have an FTDI USB serial adapter and know how to use this with Arduino environment. However, to use the adapter with a terminal program, you need to configure the terminal program properly to use it.

If you are using Windows, plug in the serial adapter and find out what it is called (e.g. COM19) by opening My Computer > Properties > Hardware > Device Manager > Ports (COM & LPT). Then start Hyperterm, set Hyperterm to open COM19 and set the baud rate to 9600, 8 bits, no parity, no flow control.

If you have RX on the serial adapter connected to TX on the OpenLog, etc. then OpenLog will be able to talk to the PC.

However, as purchased, OpenLog defaults to "data logging mode" upon startup and does not echo characters to the terminal until you close the log file. Type ^Z (ctrl-Z) on the PC keyboard to stop data logging.

Then you should see a prompt ">" Type the character ? <return> for help or type commands such as "ls <return>" to list the files on the microSD card.

If you have reprogrammed OpenLog using the Arduino software, you will have to reprogram OpenLog again with the logging software. This is contained in the file main.hex, which you can download from GitHub. Follow the instructions on the GitHub site, or search this forum for recently posted examples on how to do that. You will need to use the program avrdude to reprogram the OpenLog, and it will have to be configured to the correct COM port and baud rate (57600) to work.

Good luck, Jim
By potoole
Author Message
jremington Posted: Sun Jan 31, 2010 6:47 pm Post subject:



Yes, the documentation on the Spark Fun site on how to use OpenLog sucks.

Good luck, Jim)"

Thanks Jim. As I stated (somewhere) getting the OpenLog to work isn't as 'simple' as advertized. The "directions" are like having an operators booklet with the first half of the pages torn out. They're making a lot of assumptions about a user's knowledge of computer-eze. :roll:

I ended up sending it back for 'reflashing' after I screwed around with it, and screwing it up, for several days. When it gets back to me, I'll see if I can follow your directions to get it working. If not, I'll just have to use it in some other manner. :?

Thank you
By jremington
Spark Fun obviously did not write the documentation for OpenLog with beginners in mind. As it is, OpenLog doesn't do much. I can't imagine why the board designed didn't include a few more connections to the processor I/O pins.

Using the FTDI Basic adapter you can reflash the Openlog yourself by following the directions in the second to last post on this thread:


You may need the latest Arduino version (17) for this to work
By potoole
Yup, I'm using .0017, and I was able to download arduino sketch's("Hello world") to the OpenLog's atmega328, but nothing would show up on the CD card.

From TZ's suggestion, I finally started using Hyperterminal, and other terminal programs, but none of them worked. I thought maybe I screwed up the OpenLog by downloading the arduino sketch.

Sparkfun sent me a file for reflashing, but I couldn't get that to do anything. Something in the makefile couldn't be found (command not found). Similar line you show in that second to last reply.

Its in sparkfun's hands now.

By tz
The original versions were NOT locked to prevent the bootloader from being overwritten. So if you can't do the arduino sketch, you would need to reflash it using the ISP to the 4 lines on the far side (plus power and ground, or have Sparkfun reflash them).

For my variant (hyperlog at my site - still tweaking), I use a config file in the root of the SD card, although it only uses a single line for the baud rate. It then records out of boot and doesn't reply with anything. I have a CLI test program (fat32cli), which does more, but only works at 57600 and is a bit obscure.

You should see the "12>" (or at least the 1 part - you need a FAT16 SD card for anything else on the stock software). You might want to try different baud rates or the "baud rate recovery" and try 9600.
By jremington

Did you check that the SD card was no larger than 2 Gb and formatted as FAT16?

Since you *could* flash OpenLog with the Arduino sketch, you were almost there.

To reflash OpenLog follow these instructions:

In the directory containing the OpenLog object file (main.hex), create a batch file "flash.bat" containing the single line:

C:\arduino\hardware\tools\avr\bin\avrdude -p atmega328p -P COM1 -c stk500v1 -b 57600 -CC:\arduino\hardware\tools\avr\etc\avrdude.conf -U flash:w:main.hex

In the above make sure that the COM port is correct (it is almost certainly not COM1), that flash.bat and main.hex are in the same, default directory and that the location of avrdude is correct. Open up a DOS command line window, set default to the directory containing main.hex and flash.bat, and type flash

To use your newly reflashed version of OpenLog there is no change in the connections. Run hyperterm and connect it to the correct COM port, 9600 baud, 8 bits, no parity and 1 stop.

Type ^Z to stop logging and away you go.
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