Posted by Tim Michals on January 9, 2010 at 11:02am
Goals for this projectHave UBW32 on order, the next version has 128K of RAM so... that will be nice1) UBW32 Software porting- Use open source 4.4.x gcc compiler http://www.codesourcery.com/- Gives better code generation then current 3.3.x- Follow the general setup an ARM process has... (more on this later)- Support C++, in order to support Wiring as is the AVR supports basic C++, so need to do this...- FreeRTOS port (This is done, but, using newer gcc- USB Host support- Support wifi USB dongle ( ordered dongle, it is a 1000mw 802.11b/g)- Support Ad-doc and infrastructure mode)- Video (USB) using off the self web camera- Support of Wiring- New boot loader based on LUFA (http://www.fourwalledcubicle.com/LUFA.php also with mass storage device)- similar to mbed.org, allows users to update firmware via mass storage...- once mode USB is working... need a way to switch between the two... OTG?- SPI SD flash support.2) Simple controller (more to follow)3) Lua scripting support (allows setting simple scripting without writing a bunch of c++/c code
Read more…
Posted by Tim Michals on December 21, 2009 at 6:19am
I'm trying to find out what is the maximum update rate for a typical ESC is. I saw that most quad copter designed require the ESC update rate to be very high, i.e 100Hz or more.My understanding a ESC takes a PPM signal from 1ms to 2ms with a 20ms duty cycle. So a max of 50Hz update rate, is that correct? Is there some "play" in the duty cycle maybe max of 10ms. Or I'm way off base? Looking at ESC data sheets seem to be missing this information.
Read more…
