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QEIx4 Example
Diff: main.cpp
- Revision:
- 2:7c787d83331e
- Parent:
- 0:bbf48777e304
- Child:
- 3:922c100de8cd
--- a/main.cpp Tue Sep 02 18:29:18 2014 +0000 +++ b/main.cpp Tue Sep 30 12:35:07 2014 +0000 @@ -1,32 +1,52 @@ #include "mbed.h" #include "QEIx4.h" -DigitalOut myled(LED1); +DigitalOut LEDalive(LED1); +DigitalOut LEDup(LED4); +DigitalOut LEDdown(LED3); + Timer t; // ports for nxp LPC 1768 -QEIx4 qei1(p30, p29, p28); // QEI with index signal for zeroing -QEIx4 qei2(p27, p26, NC); // QEI only with AB signals -QEIx4 qei3(p25, p24, NC, false); // QEI without interrups for polling mode +QEIx4 qei1(p30, p29, p28, (QEIx4::EMODE)(QEIx4::IRQ | QEIx4::SPEED)); // QEI with index signal for zeroing +QEIx4 qei2(p21, p22, NC, QEIx4::IRQ_NO_JAMMING); // QEI with AB signals only +QEIx4 qei3(p25, p24, NC, QEIx4::POLLING); // QEI without interrups in polling mode + +// The callback function. +void myCallback(int value) +{ + static int valueLast=-1; -int main() { + if ( value > valueLast ) { + LEDup = !LEDup; + LEDdown = 0; + } else { + LEDdown = !LEDdown; + LEDup = 0; + } + valueLast=value; +} + +int main() +{ t.start(); - qei1.SetZeroOnIndex(true); // Set the flag to zero counter on next index signal rises + qei1.setZeroOnIndex(true); // set the flag to zero counter on next index signal rises + qei1.setSpeedFactor(1.0f); // factor to scale from Hz (edges pe second = 4 * CPS) to user units (1.0=Hz, 1/(4*CPR)=rps, 1/(60*4*CPR)=rpm, 360/(4*CPR)=°/s, ...) + + qei3.attachCounterChange(myCallback); - while(1) - { + while(1) { qei3.poll(); // poll manually without interrupt - sampling in this loop with about 2kHz - - if ( t.read_ms() > 500 ) // every half second - { + + if ( t.read_ms() > 250 ) { // every quater second (4 Hz) t.reset(); t.start(); - myled = !myled; - - printf ( "\r\n%6d %6d %6d", (int)qei1, (int)qei2, (int)qei3 ); // print counter values + LEDalive = !LEDalive; + + printf ( "\r\n%6d %6d %6d %10.3f", (int)qei1, (int)qei2, (int)qei3, (float)qei1.getSpeed() ); // print counter values } - wait_us(500); // for about 2kHz + wait_us(20); // for about 50kHz polling } }