Tag Archives: c++
The old version of readesm was using a command-line interface to convert the tachograph data into html. If one wanted it shown in the browser, there was a script to convert the file, write it to a temporary directory, and then open that file in the browser. However, this approach turned out to be not portable at all.
There were other problems: readesm was using custom Makefiles, which apparently made compiling the source difficult. I was amazed to discover this wiki entry for fahrlinx, which contained information on how to install the windows version of readesm using wine. As the windows version at that time was cross-compiled in linux and lacked some features, readesm was clearly too difficult to compile.
LCD Controllers using an HD44780 Display Controller are commonly used for small batch electronic devices, and are popular with electronics fans worldwide. One problem with those controllers is their demand for IO-lines, due too the parallel interface they require at least 7 IO lines.
One solution, if you don’t have enough IO ports to spare, is to use another Display, like serial cellphone displays, which are cheap and color is a great thing to show off. Or you can expand the number of IO lines by using a shift register or TWI device. This is one such implementation using a 74hc164 shift register. It is based on an implementation by Peter Dannegger. If you prefer to use a 4094 cmos shift register, there are also schematics floating around the net.
Update, March 2011: There is a new release of readesm, The description provided here no longer applies, the new readesm uses Qt and cmake. You can get the new release at the sourceforge project page and read the documentation here.
For several years now, new trucks sold in the European union are equipped with digital tachographs, that record the driving times and replace the older chart-based mechanical tachographs.