AS5048A SPI - Magnetic rotary encoder library
Library for communication over the SPI interface with the ams.com AS5048A magnetic rotary encoder.
Example:
Simple readout of a single angle measurement from a single sensor on the SPI-bus
#include "mbed.h" #include <as5048spi.h> // The sensors connection are attached to pins 5-8 As5048Spi sensor(p5, p6, p7, p8); Serial pc(USBTX, USBRX); // tx, rx int main() { while(1) { // const int* angles = sensor.read_angle(); int angle = angles[0]; // The read angle returns the value returned over the SPI bus, including parity bit pc.printf("Read result: %x\r\n", angle); if( As5048Spi::parity_check(angle) ) { // Convert range from 0 to 2^14-1 to 0 - 360 degrees int degrees = As5048Spi::degrees(angle)/100; pc.printf("Parity check succesfull.\r\n"); pc.printf("Angle: %i degrees\r\n", degrees ); } else { pc.printf("Parity check failed.\r\n"); } wait_ms(500); } }
The class supports daisy chaining multiple sensors on the SPI-bus as well. See: SPI-Daisy-Chaining.
Diff: as5048spi.cpp
- Revision:
- 2:2958500883e0
- Parent:
- 1:f2ed22514649
diff -r f2ed22514649 -r 2958500883e0 as5048spi.cpp --- a/as5048spi.cpp Thu Sep 18 19:28:25 2014 +0000 +++ b/as5048spi.cpp Thu Dec 04 10:00:42 2014 +0000 @@ -59,6 +59,15 @@ return sensor_result & 0x3FFF; // return lowest 14-bits } + +void As5048Spi::mask(int* sensor_results, int n) +{ + for(int i = 0; i < n; ++i) { + sensor_results[i] &= 0x3FFF; + } +} + + bool As5048Spi::parity_check(int sensor_result) { // Use the LSb of result to keep track of parity (0 = even, 1 = odd)