mirror of
https://github.com/bjoernellens1/cps_microros_imu.git
synced 2024-11-23 00:23:47 +00:00
114 lines
4.9 KiB
Plaintext
114 lines
4.9 KiB
Plaintext
/* Encoder Library - SpeedTest - for measuring maximum Encoder speed
|
|
* http://www.pjrc.com/teensy/td_libs_Encoder.html
|
|
*
|
|
* This example code is in the public domain.
|
|
*/
|
|
|
|
|
|
// This SpeedTest example provides a simple way to verify how much
|
|
// CPU time Encoder is consuming. Connect a DC voltmeter to the
|
|
// output pin and measure the voltage while the encoder is stopped
|
|
// or running at a very slow speed. Even though the pin is rapidly
|
|
// pulsing, a DC voltmeter will show the average voltage. Due to
|
|
// software timing, it will read a number much less than a steady
|
|
// logic high, but this number will give you a baseline reading
|
|
// for output with minimal interrupt overhead. Then increase the
|
|
// encoder speed. The voltage will decrease as the processor spends
|
|
// more time in Encoder's interrupt routines counting the pulses
|
|
// and less time pulsing the output pin. When the voltage is
|
|
// close to zero and will not decrease any farther, you have reached
|
|
// the absolute speed limit. Or, if using a mechanical system where
|
|
// you reach a speed limit imposed by your motors or other hardware,
|
|
// the amount this voltage has decreased, compared to the baseline,
|
|
// should give you a good approximation of the portion of available
|
|
// CPU time Encoder is consuming at your maximum speed.
|
|
|
|
// Encoder requires low latency interrupt response. Available CPU
|
|
// time does NOT necessarily prove or guarantee correct performance.
|
|
// If another library, like NewSoftSerial, is disabling interrupts
|
|
// for lengthy periods of time, Encoder can be prevented from
|
|
// properly counting the intput signals while interrupt are disabled.
|
|
|
|
|
|
// This optional setting causes Encoder to use more optimized code,
|
|
// but the downside is a conflict if any other part of your sketch
|
|
// or any other library you're using requires attachInterrupt().
|
|
// It must be defined before Encoder.h is included.
|
|
//#define ENCODER_OPTIMIZE_INTERRUPTS
|
|
|
|
#include <Encoder.h>
|
|
#include "pins_arduino.h"
|
|
|
|
// Change these two numbers to the pins connected to your encoder
|
|
// or shift register circuit which emulates a quadrature encoder
|
|
// case 1: both pins are interrupts
|
|
// case 2: only first pin used as interrupt
|
|
Encoder myEnc(5, 6);
|
|
|
|
// Connect a DC voltmeter to this pin.
|
|
const int outputPin = 12;
|
|
|
|
/* This simple circuit, using a Dual Flip-Flop chip, can emulate
|
|
quadrature encoder signals. The clock can come from a fancy
|
|
function generator or a cheap 555 timer chip. The clock
|
|
frequency can be measured with another board running FreqCount
|
|
http://www.pjrc.com/teensy/td_libs_FreqCount.html
|
|
|
|
+5V
|
|
| Quadrature Encoder Signal Emulator
|
|
Clock |
|
|
Input o----*-------------------------- ---------------------------o Output1
|
|
| |14 | |
|
|
| _______|_______ | | _______________
|
|
| | CD4013 | | | | CD4013 |
|
|
| 5 | | 1 | | 9 | | 13
|
|
---------| D Q |-----|----*----| D Q |------o Output2
|
|
| | | | | | |
|
|
| | 3 | | | 11 | |
|
|
| ----|> Clk | ---------|> Clk |
|
|
| | | | |
|
|
| 6 | | 8 | |
|
|
| ----| S | ----| S |
|
|
| | | | | | |
|
|
| | 4 | _ | 2 | 10 | _ | 12
|
|
| *----| R Q |--- *----| R Q |----
|
|
| | | | | | | |
|
|
| | |_______________| | |_______________| |
|
|
| | | | |
|
|
| | | 7 | |
|
|
| | | | |
|
|
--------------------------------------------------------------
|
|
| | |
|
|
| | |
|
|
----- ----- -----
|
|
--- --- ---
|
|
- - -
|
|
*/
|
|
|
|
|
|
void setup() {
|
|
pinMode(outputPin, OUTPUT);
|
|
}
|
|
|
|
#if defined(__AVR__)
|
|
#define REGTYPE unsigned char
|
|
#elif defined(__PIC32MX__)
|
|
#define REGTYPE unsigned long
|
|
#endif
|
|
|
|
void loop() {
|
|
volatile int count = 0;
|
|
volatile REGTYPE *reg = portOutputRegister(digitalPinToPort(outputPin));
|
|
REGTYPE mask = digitalPinToBitMask(outputPin);
|
|
|
|
while (1) {
|
|
myEnc.read(); // Read the encoder while interrupts are enabled.
|
|
noInterrupts();
|
|
*reg |= mask; // Pulse the pin high, while interrupts are disabled.
|
|
count = count + 1;
|
|
*reg &= ~mask;
|
|
interrupts();
|
|
}
|
|
}
|
|
|