Mastodawn

cyclical_obsessive Apr 11, 2024

Another Successful Work-Around For My #robot

I've always thought my autonomous robots don't have to be fast, just function packed and reliable.

I've been battling early SPI chip select release on Raspberry Pi 5 at 500kHz (488 kHz actually) max transfer rate with the #GoPiGo3 robot.

Slowing #SPI transfers down to the next available max rate - 250kHz (244 kHz actual) eliminates the exceptions, and appears to still be "fast enough".

Feeling good, but know another dragon always awaits.

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cyclical_obsessive

At this reduced transfer rate, the #GoPiGo3 can make a two byte #SPI transfer in 0.0003 seconds, which means it can retrieve the left and right wheel encoder values roughly 1700 times per second - plenty fast enough for my #ros2humble robot to publish #wheelencoders and the resultant #odometry at 30 Hz.