필수 코드는 다음과 같습니다
#define qap 2 // Quick As Possible ... Duty cycle only 0, 50, 100%
#define HFreq 5150
#define pPulse D2 // a NodeMCU/ESP8266 GPIO PWM pin
analogWriteRange(qap); analogWriteFreq(HFreq); analogWrite(pPulse, 1); // start PWM
TL; DR 그냥 80 MHz 클럭과
// had HFreq=126400 with 75 KHz pulse at 80 MHz ESP clock, every 1 sec but proof of evidence lost
명목상 일부 원유 benchamrks에게
했다
// 72.24 KHz 361178 2015061929
// 72.23 KHz 361163 2415062390
// 72.23 KHz 361133 2815062824
및
있어
160MHz 클록
주의!
1. 듀티 사이클 범위는 2입니다!
2. 시스템에는 다른 컨디셔닝이 없었기 때문에 직렬 IO 등에서 다른 타이밍 아티팩트가 여전히 존재했습니다. 특히 WDT 및 WiFi로 인한 불안정성이 두 번째로 나타났습니다. (여하튼, 아마도 이것은 ESP8266 스트레스와 협박 만하는 문제가있다.)
// 141.50 KHz 353754 619466806
// 141.52 KHz 353810 1019467038
// ...
// ad infinitum cum tempore finitum, infinitus est ad nauseum?
// ...
// 141.54 KHz 353857 735996888
//
// ets Jan 8 2013,rst cause:4, boot mode:(1,7)
//
//wdt reset
5 KHz의 사각 파 신호를 생성하기 위해 다음과 같은 코드를 사용하여 고려 상기 문제없고하지 나오다.
// ------------ test results for 80 MHz clock --------------
//
//
// PWM pulse test
//
// F_CPU: 80000000L
// ESP8266_CLOCK: 80000000UL
// PWM "freq.": 5150
//
//
// connect D1 to D2
//
//
// raw MPU
// frequency count cycle
// 0.00 KHz 1 407976267
// 4.74 KHz 9482 567976702
// 5.00 KHz 10007 727977137
// 5.00 KHz 10006 887977572
// 5.00 KHz 10006 1047978007
// 5.00 KHz 10007 1207978442
// 5.00 KHz 10006 1367978877
// 5.00 KHz 10006 1527979312
// 5.00 KHz 10007 1687979747
// 5.00 KHz 10006 1847980182
// 5.00 KHz 10006 2007980617
// 5.00 KHz 10007 2167981052
// 5.00 KHz 10006 2327981487
// 5.00 KHz 10006 2487981922
// 5.00 KHz 10007 2647982357 ...
//
// crude testing for 5KHz signal
// extracted from:
// highest frequency/shortest period pin pulse generate/detect test
//
// uses raw ESP8266/NodeMCU V1.0 hardware primitive interface of Arduino IDE (no included libraries)
//
// timing dependencies: WDT, WiFi, I2S, I2C, one wire, UART, SPI, ...
//
// Arduino GPIO 16 5 4 0 2 14 12 13 15 3 1 0 1 2 3 4 5 ... 12 13 14 15 16
// NodeMCU D pin 0 1 2 3 4 5 6 7 8 9 10 3 10 4 9 2 1 ... 6 7 5 8 0
// | | | | | | | | | | |
// a WAKE | | F Tx1 | | Rx2 Tx2 Rx0 Tx0
// k (NO PWM or | | L blue | | | |
// a' interrupt) | S A * H | H | H | | * led's
// s red S D S S M S H
// * C A H C I I C
// L T L S M S
// K A K O O
// └ - - - - └----UART's----┘
// └--I2C--┘ └-----SPI------┘
//
// rules of engagement are obscure and vague for effects of argument values for the paramters of these functions:
// analogWriteRange(qap); analogWriteFreq(HFreq); analogWrite(pPulse, 1);
//
// http://stackoverflow.com/questions/42112357/how-to-implement-esp8266-5-khz-pwm
//
// system #defines: F_CPU ESP8266_CLOCK
#define pInt D1 // HWI pin: NOT D0 ie. GPIO16 is not hardwared interrupt or PWM pin
#define pPulse D2 // PWM pulsed frequency source ... ditto D0 (note: D4 = blue LED)
#define countFor 160000000UL
#define gmv(p) #p // get macro value
#define em(p) gmv(p) // evaluate macro
#define qap 2 // minimal number of duty cycle levels (0, 50, 100%) Quick As Possible ...
#define HFreq 5150 //((long int) F_CPU==80000000L ? 125000 : 250000) // ... to minimize time of a cycle period
// max values ^ and ^ found empirically
// had HFreq=126400 with 75 KHz pulse at 80 MHz ESP clock, every 1 sec but proof of evidence lost
#define infoTxt (String) \
"\n\n\t PWM pulse test " \
"\n F_CPU: " em(F_CPU) \
"\n ESP8266_CLOCK: " em(ESP8266_CLOCK) \
"\n PWM \"freq.\": " + HFreq + "\n" \
"\n\n connect " em(pInt) " to " em(pPulse) "\n" \
"\n\n raw MPU " \
" \n frequency count cycle "
long int oc=1, cntr=1;
unsigned long int tc=0;
void hwISR(){ cntr++; } // can count pulses if pInt <---> to pPulse
void anISR(){ tc=ESP.getCycleCount(); timer0_write(countFor + tc); oc=cntr; cntr=1; }
void setup() { // need to still confirm duty cycle=50% (scope it or ...)
noInterrupts();
Serial.begin(115200); Serial.println(infoTxt); delay(10); // Serial.flush(); Serial.end(); // Serial timing?
analogWriteRange(qap); analogWriteFreq(HFreq); analogWrite(pPulse, 1); // start PWM
pinMode(pInt, INPUT); attachInterrupt(pInt, hwISR, RISING); // count pulses
timer0_isr_init(); timer0_attachInterrupt(anISR); anISR(); //
interrupts();
}
void loop() { delay(10); if (oc==0) return;
Serial.println((String)" "+(oc/1000.0*F_CPU/countFor)+" KHz "+oc+" "+tc); oc=0; }
//
'analogWriteFreq (5000);'가 도움이됩니까? – dandavis