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HP Forum Archive 21

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USB flashing/Li-po boards
Message #1 Posted by patryk on 7 Sept 2013, 1:20 p.m.

Are these still available? Since the programming cables seem to be unavailable, I was thinking about soldering it onto the 30b board, flashing, and then removing it.

      
Re: USB flashing/Li-po boards
Message #2 Posted by Marcus von Cube, Germany on 7 Sept 2013, 2:05 p.m.,
in response to message #1 by patryk

Don't remove it, leave it in for updates and communication with the PC or Mac. I think Harald Pott still sells the boards. The "normal" USB board with power and LED support should suffice.

            
Re: USB flashing/Li-po boards
Message #3 Posted by patryk on 7 Sept 2013, 2:36 p.m.,
in response to message #2 by Marcus von Cube, Germany

Come to think of it, would something like this work?

If I connected the TX, RX, etc, to the appropriate pads among the set of 6, would it work?

                  
Re: USB flashing/Li-po boards
Message #4 Posted by Marcus von Cube, Germany on 7 Sept 2013, 3:39 p.m.,
in response to message #3 by patryk

Yes it will work. I've used an FTDI 3.3V cable instead, connected through a 2.5mm stereo jack. Here is the story.

                        
Re: USB flashing/Li-po boards
Message #5 Posted by patryk on 7 Sept 2013, 3:52 p.m.,
in response to message #4 by Marcus von Cube, Germany

Very cool project. From your work it seems that only Tx, Rx, and ground need to be connected (assuming reset and erase are handled separately). Is this correct?

                              
Re: USB flashing/Li-po boards
Message #6 Posted by Marcus von Cube, Germany on 8 Sept 2013, 8:31 a.m.,
in response to message #5 by patryk

You are right. ERASE is just a short between two pads (the erase pin and +3V). RESET is available as a separate button on the device (there is a tiny hole in the back).

The simple connection with the 2.5mm jack seems cool but implanting one of Harald's boards is way cooler. d:-D

                                    
Re: USB flashing/Li-po boards
Message #7 Posted by patryk on 8 Sept 2013, 12:31 p.m.,
in response to message #6 by Marcus von Cube, Germany

Using an FTDI breakout board, I was able to reflash a 34S with a broken LCD and no other issues, but experienced some strange issues. This 34S had the crystal installed and had the calc_xtal_full firmware. I put it in bootloader mode and was able to flash the calc_full (not calc_xtal_full) firmware right away. After the flashing, it would randomly turn off after I turned it on, sometimes right away, sometimes after tens of minutes. So, I flashed calc_full again, again without any issues. The calculator was still randomly turning off, so I put it into bootloader mode again (now the third time) and tried to flash calc_xtal_full, but I'm not able to. The calculator isn't giving any response to the programming attempts. Any idea what the issue could be?


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