TowerPro 17A and 25A ESC types, conversion guides, and firmware files
Note that this guide is for the newer type 2 ESCs which came to market from approx. September 2007 onwards. The older type 1 version had a slightly different layout, but in other respect were similar. Externally, in their yellow heatshrink, they are identical unless your recognize the different pattern of bulges due to the different location of voltage regulators on the processor side.
A conversion guide for the TowerPro 17A ESCs, which have an identical layout and for which the same conversion applies can be found here: http://home.versanet.de/~b-konze/low...18a_regler.htm
(in German but with pics, so probably reasonably understandable, certainly if held next to this guide).
is also the location were the firmware files needed for the conversion of both the type 1 17A and 25A, and the type 2 25A ESCs can be found. At this time the most current version of the ZIP file with source code and the compiled HEX files is: http://home.versanet.de/~b-konze/low...10_i2c_r07.zip
Please note that there are some other ZIP files there for several other types of ESCs. You need the correct file. Using an incorrect file may damage the ESC or motor !!!
So again for the TowerPro 25A type 1 and type 2 ESCs you need a file 17a410_i2c_r##.zip (## denoting the version number) for controling them over the TWI/I2C interface. Other interesting files could be the 17a410_ppm_r##.zip, which allows to resinstal PWM based control.