Prof Prabhat Ranjan's Blog

Prof. Prabhat Ranjan is Vice Chancellor of D Y Patil International University, Akurdi, Pune

TinyOS-2.x on Zigbit – Baud rate mismatch

We tried to use TinyOS on Meshnetics Meshbean modules based on Zigbit module containing both microcontroller and radio transceiver. Fortunately a port was made available as a contributed code. I got many student group to start using TinyOS on Meshbean modules. However no one could get the UART communication through USB port working and all the projects which needed this got stalled. I took up this task as I got little free now to figure out what may be happening. It looked like a Baud Mismatch problem since we were received some characters but no baud rate setting was making

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Joomla Media Manager image upload fail

One of my websites, which uses Joomla as CMS got hacked as I had not paid attention to securing the site properly. After this I did go through the site carefully trying to remove any possible loopholes. Recently I realized that Uploading images through Media Manager or any other means were failing to upload. I tried various things but nothing was helping. I am listing some of them here: 1. Checking the Directory permissions. Even tried changing the unsafe mode of 777 to all the relevant directory. Did not help. 2. Tried disabling Flash based uploader – did not  help.

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Meshprog – USB device opening failure on Fedora 11/12

I had been using meshprog to program Meshnetics Zigbit Evaluation Modules on Linux. I discovered that it was not getting programmed on Fedora 11 or 12. It took me some time to figure out what was happening. I am recording this here in case some one else faces the same problem. Here are my observations: 1. Meshnetics modules use UART to USB converter from Silicon Labs – CP2102. This has idVendor=10c4, idProduct=ea60 as shown by Kernel message. 2. I found that /dev/ttyUSBx to which it was getting attached was not opening by Meshprog 3. System log showed the following :

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