Quote:
Originally Posted by etlaare
Jack once opted to have a possibility to set the pwm switching frequency as a parameter. I still think that would be a nice addition, as it would make experimenting with different frequencies eassier as it is now with using different .hex files.
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Basically what it comes down to is less noise more heat (16kHz) or more noise less heat (8kHz). The controller was designed to operate at the least noise possible and smoothest power control, hence the 16kHz. The 8kHz version came along with to allow people (Jack to start) to build IGBT based controllers out of IGBT's that were gotten from ebay with less then optimal switching speeds. In this case, they could not handle the turn off at high frequency and created a very bad negative voltage spike on turn off...16K times per second. Why is it you want to be able to change the frequency anyways? Also, as of the last release of the firmware, v1.11b, the atmega8 micro controller on the controllers is completely full. I believe that there is only a few bytes remaining.
Quote:
Originally Posted by etlaare
I might have missed something in Paul's thread, but do I need extra hardware to use the bootloader ? Or is it just my usb-rs232 that messes up when I want to upgrade the firmware ?
oh oh ... two subjects in one post *blush* ... (ah well, they are sort of related as I want to test at 8Khz and it won't load atm...).
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NO, all you need to boot-load new firmware onto the controller is a serial adapter or port, and RTD Explorer or command line boot-loader.
What is happening when you try to boot-load? Once I know exactly what is happening I will be able to direct you.
-Adam