I upgraded from revision 26 to 35 and my code slowed down from updating at 1600 Hz to 1400 Hz. How do I downgrade the mbed library version so that I can figure out exactly what revision caused this?

For reference, here is my test program: http://mbed.org/users/allanw/programs/rgbstick/m3w6df

It generates data for cascaded TLC5947 which is a 24 channel 12-bit shift register for driving LED's. The code does pure integer HSV to RGB and has a look-up table for gamma correction. The update frequency is measured by looking for the latch() call on an oscilloscope.

I also noticed my binary size shrank from 35KB to 24KB but I'm not sure what that means exactly.

Hi Allan,

You can just delete the mbed library and reimport at the specific version using @, so in this case you'd imprt using the url:

http://mbed.org/projects/libraries/svn/mbed/trunk@26

Hope that is what you were after,

Simon

Thanks. I found there's a 10% speed regression between 31 and 32. I've made a smaller testcase program and found that the problem is purely due to the SPI calls. I'll post in the bugs forum with more details.

Great, thanks!