Merge branch 'docu-3.16' into patch-1
This commit is contained in:
mstroh
@@ -20,13 +20,13 @@ sudo apt install git
|
||||
git clone https://github.com/WiringPi/WiringPi.git
|
||||
cd WiringPi
|
||||
./build debian
|
||||
mv debian-template/wiringpi-3.0-1.deb .
|
||||
mv debian-template/wiringpi_3.16_arm64.deb .
|
||||
```
|
||||
|
||||
**Debian-Paket installieren:**
|
||||
|
||||
```bash
|
||||
sudo apt install ./wiringpi-3.0-1.deb
|
||||
sudo apt install ./wiringpi_3.16_arm64.deb
|
||||
```
|
||||
|
||||
**Debian-Paket deinstallieren:**
|
||||
@@ -125,10 +125,8 @@ mehr benutzt werden!
|
||||
|
||||
**Ab Version 3.4:**
|
||||
``wiringPiSetupPinType`` entscheidet ob nun WiringPi, BCM oder physische Pin-Nummerierung verwendet wird, anhand des Parameters pinType. Es führt also die ersten 3 Setup-Funktionen auf eine zusammen.
|
||||
``wiringPiSetupGpioDevice`` ist der Nachfolger der ``wiringPiSetupSys`` Funktion und verwendet nun "GPIO Character Device Userspace API" in Version 1 (ab Kernel 5.10 verfügbar). Nähere Informationen findet man bei https://docs.kernel.org/driver-api/gpio/driver.html. Anhand des Parameters pinType wird wieder entschieden, welche Pin-Nummerierung verwendet wird.
|
||||
Bei dieser Variante wird nicht direkt auf den GPIO-Speicher (DMA) zugegriffen sondern über eine Kernel Schnittstelle, die mit Benutzerrechten verfügbar ist. Nachteil ist der eingeschrenkte Funktionsumfang und die niedrige Performance.
|
||||
|
||||
<!-- Achtung Code der die neunen Funktionen benutzt ist nicht mehr mit der älterer Library Versionen 2 kompatibel! -->
|
||||
``wiringPiSetupGpioDevice`` ist der Nachfolger der ``wiringPiSetupSys`` Funktion und verwendet nun "GPIO Character Device Userspace API" in Version 2 (ab WiringPi Version 3.16). Nähere Informationen findet man bei https://docs.kernel.org/driver-api/gpio/driver.html. Anhand des Parameters pinType wird wieder entschieden, welche Pin-Nummerierung verwendet wird.
|
||||
Bei dieser Variante wird nicht direkt auf den GPIO-Speicher (DMA) zugegriffen sondern über eine Kernel Schnittstelle, die mit Benutzerrechten verfügbar ist. Nachteil ist der eingeschränkte Funktionsumfang und die niedrige Performance.
|
||||
|
||||
|
||||
### wiringPiSetup V2 (veraltet)
|
||||
@@ -288,6 +286,7 @@ if (value==HIGH)
|
||||
### wiringPiISR
|
||||
|
||||
Registriert eine Interrupt Service Routine (ISR) bzw. Funktion die bei Flankenwechsel ausgeführt wird.
|
||||
Es werden bei dieser klassischen Version keine Parameter and die ISR übergeben.
|
||||
|
||||
>>>
|
||||
```C
|
||||
@@ -305,8 +304,44 @@ int wiringPiISR(int pin, int mode, void (*function)(void));
|
||||
> 0 ... Erfolgreich
|
||||
<!-- > <>0 ... Fehler, zur Zeit nicht implementiert -->
|
||||
|
||||
Beispiel siehe wiringPiISRStop.
|
||||
Beispiel siehe [wiringPiISRStop](#wiringPiISRStop).
|
||||
|
||||
### wiringPiISR2
|
||||
|
||||
Registriert eine Interrupt Service Routine (ISR) bzw. Funktion die bei Flankenwechsel ausgeführt wird.
|
||||
Es werden erweiterte Parameter an die ISR übergeben.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int wiringPiISR2(int pin, int edgeMode, void (*function)(struct WPIWfiStatus wfiStatus, void* userdata), unsigned long debounce_period_us, void* userdata);
|
||||
```
|
||||
|
||||
``pin``: Der gewünschte Pin (BCM\-, WiringPi\- oder Pin\-Nummer).
|
||||
|
||||
``edgeMode``: Auslösender Flankenmodus
|
||||
|
||||
- INT_EDGE_RISING ... Steigende Flanke
|
||||
- INT_EDGE_FALLING ... Fallende Flanke
|
||||
- INT_EDGE_BOTH ... Steigende und fallende Flanke
|
||||
|
||||
``*function``: Funktionspointer für ISR mit Parameter struct WPIWfiStatus und einem Pointer:
|
||||
```C
|
||||
struct WPIWfiStatus {
|
||||
int statusOK; // -1: error (return of 'poll' command), 0: timeout, 1: irq processed, next data values are valid if needed
|
||||
unsigned int pinBCM; // gpio as BCM pin
|
||||
int edge; // INT_EDGE_FALLING or INT_EDGE_RISING
|
||||
long long int timeStamp_us; // time stamp in microseconds
|
||||
};
|
||||
```
|
||||
|
||||
``debounce_period_us``: Entprellzeit in Microsekunden, 0 schaltet das Entprellen ab
|
||||
``userdata``: Pointer der beim Aufruf der ISR übergeben wird
|
||||
|
||||
``Rückgabewert``:
|
||||
> 0 ... Erfolgreich
|
||||
<!-- > <>0 ... Fehler, zur Zeit nicht implementiert -->
|
||||
|
||||
Beispiel siehe [waitForInterrupt2](#waitForInterrupt2).
|
||||
|
||||
### wiringPiISRStop
|
||||
|
||||
@@ -314,50 +349,215 @@ Deregistriert die Interrupt Service Routine (ISR) auf einem Pin.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int wiringPiISRStop (int pin)
|
||||
int wiringPiISRStop (int pin);
|
||||
```
|
||||
|
||||
``pin``: Der gewünschte Pin (BCM-, WiringPi- oder Pin-Nummer).
|
||||
``Rückgabewert``:
|
||||
|
||||
> 0 ... Erfolgreich
|
||||
<!-- > <>0 ... Fehler, zur Zeit nicht implementiert -->
|
||||
|
||||
|
||||
**Beispiel:**
|
||||
|
||||
>>>
|
||||
```C
|
||||
static volatile int edgeCounter;
|
||||
|
||||
static void isr(void) {
|
||||
static void isr(void) {
|
||||
edgeCounter++;
|
||||
}
|
||||
|
||||
int main (void) {
|
||||
wiringPiSetupPinType(WPI_PIN_BCM);
|
||||
edgeCounter = 0;
|
||||
wiringPiISR (17, INT_EDGE_RISING, &isr);
|
||||
|
||||
wiringPiISR(17, INT_EDGE_RISING, &isr);
|
||||
|
||||
Sleep(1000);
|
||||
printf("%d rinsing edges\n", )
|
||||
wiringPiISRStop(17) ;
|
||||
printf("%d rising edges\n", edgeCounter);
|
||||
|
||||
wiringPiISRStop(17);
|
||||
}
|
||||
```
|
||||
|
||||
|
||||
### waitForInterrupt
|
||||
|
||||
Wartet auf einen zuvor definierten Interrupt (wiringPiISR) am GPIO Pin. Diese Funktion sollte nicht verwendet werden.
|
||||
Funktion ist nicht mehr verfügbar, es wird nur noch die ``waitForInterrupt2`` unterstützt!
|
||||
|
||||
|
||||
### waitForInterrupt2
|
||||
|
||||
Wartet auf einen Aufruf der Interrupt Service Routine (ISR) mit Timeout und Entprellzeit in Mikrosekunden.
|
||||
Blockiert das Programm bis zum Eintreffen der auslösenden Flanke oder bis zum Ablauf des Timeouts.
|
||||
Diese Funktion sollte nicht verwendet werden.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int waitForInterrupt (int pin, int mS)
|
||||
struct WPIWfiStatus wfiStatus waitForInterrupt2(int pin, int edgeMode, int ms, unsigned long debounce_period_us)
|
||||
```
|
||||
|
||||
``pin``: Der gewünschte Pin (BCM-, WiringPi- oder Pin-Nummer).
|
||||
``mS``: Timeout in Milisekunden.
|
||||
``Rückgabewert``: Fehler
|
||||
> 0 ... Erfolgreich
|
||||
> -1 ... GPIO Device Chip nicht erfolgreich geöffnet
|
||||
> -2 ... ISR wurde nicht registriert (wiringPiISR muss aufgerufen werden)
|
||||
``pin``: Der gewünschte Pin (BCM\-, WiringPi\- oder Pin\-Nummer).
|
||||
``edgeMode``: Auslösender Flankenmodus
|
||||
|
||||
- INT_EDGE_RISING ... Steigende Flanke
|
||||
- INT_EDGE_FALLING ... Fallende Flanke
|
||||
- INT_EDGE_BOTH ... Steigende und fallende Flanke
|
||||
|
||||
``ms``: Timeout in Milisekunden.
|
||||
- \-1 ... Warten ohne Timeout
|
||||
- 0 ... Wartet nicht
|
||||
- 1-n ... Wartet maximal n Millisekunden
|
||||
|
||||
``debounce_period_us``: Entprellzeit in Microsekunden, 0 schaltet Entprellen ab.
|
||||
|
||||
``Rückgabewert``:
|
||||
```C
|
||||
struct WPIWfiStatus {
|
||||
int statusOK; // -1: error (return of 'poll' command), 0: timeout, 1: irq processed, next data values are valid if needed
|
||||
unsigned int pinBCM; // gpio as BCM pin
|
||||
int edge; // INT_EDGE_FALLING or INT_EDGE_RISING
|
||||
long long int timeStamp_us; // time stamp in microseconds
|
||||
};
|
||||
```
|
||||
|
||||
**Beispiel:**
|
||||
|
||||
```C
|
||||
/*
|
||||
* isr_debounce.c:
|
||||
* Wait for Interrupt test program WiringPi >=3.16 - ISR2 method
|
||||
*
|
||||
*
|
||||
*/
|
||||
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
#include <errno.h>
|
||||
#include <stdlib.h>
|
||||
#include <unistd.h>
|
||||
#include <wiringPi.h>
|
||||
#include <time.h>
|
||||
|
||||
#define BOUNCETIME 3000 // microseconds
|
||||
#define BOUNCETIME_WFI 300
|
||||
#define TIMEOUT 10000
|
||||
//*************************************
|
||||
// BCM pins
|
||||
// IRQpin : setup as input with internal pullup. Connected with push button to GND with 1K resistor in series.
|
||||
// OUTpin : connected to a LED with 470 Ohm resistor in series to GND. Toggles LED with every push button pressed.
|
||||
//*************************************
|
||||
#define IRQpin 16
|
||||
#define OUTpin 12
|
||||
|
||||
int toggle = 0;
|
||||
|
||||
static void wfi(struct WPIWfiStatus wfiStatus, void* userdata) {
|
||||
// struct timeval now;
|
||||
long long int timenow, diff;
|
||||
struct timespec curr;
|
||||
char *edgeType;
|
||||
|
||||
if (clock_gettime(CLOCK_MONOTONIC, &curr) == -1) {
|
||||
printf("clock_gettime error");
|
||||
return;
|
||||
}
|
||||
|
||||
timenow = curr.tv_sec * 1000000LL + curr.tv_nsec/1000L; // convert to microseconds
|
||||
diff = timenow - wfiStatus.timeStamp_us;
|
||||
if (wfiStatus.edge == INT_EDGE_RISING)
|
||||
edgeType = "rising";
|
||||
else if (wfiStatus.edge == INT_EDGE_FALLING)
|
||||
edgeType = "falling";
|
||||
else
|
||||
edgeType = "none";
|
||||
printf("gpio BCM = %d, IRQ edge = %s, timestamp = %lld microseconds, timenow = %lld, diff = %lld\n", wfiStatus.gpioPin, edgeType, wfiStatus.timeStamp_us, timenow, diff);
|
||||
if (toggle == 0) {
|
||||
digitalWrite (OUTpin, HIGH);
|
||||
toggle = 1;
|
||||
}
|
||||
else {
|
||||
digitalWrite (OUTpin, LOW);
|
||||
toggle = 0;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
int main (void)
|
||||
{
|
||||
int major, minor;
|
||||
wiringPiVersion(&major, &minor);
|
||||
printf("\nISR debounce test (WiringPi %d.%d)\n\n", major, minor);
|
||||
|
||||
wiringPiSetupGpio();
|
||||
pinMode(IRQpin, INPUT);
|
||||
// pull up/down mode (PUD_OFF, PUD_UP, PUD_DOWN) => down
|
||||
pullUpDnControl(IRQpin, PUD_UP);
|
||||
pinMode(OUTpin, OUTPUT);
|
||||
digitalWrite (OUTpin, LOW) ;
|
||||
|
||||
printf("Testing waitForInterrupt on both edges IRQ @ GPIO%d, timeout is %d\n", IRQpin, TIMEOUT);
|
||||
struct WPIWfiStatus wfiStatus = waitForInterrupt2(IRQpin, INT_EDGE_BOTH, TIMEOUT, BOUNCETIME_WFI);
|
||||
if (wfiStatus.status < 0) {
|
||||
printf("waitForInterrupt returned error\n");
|
||||
pinMode(OUTpin, INPUT);
|
||||
return 0;
|
||||
}
|
||||
else if (wfiStatus.status == 0) {
|
||||
printf("waitForInterrupt timed out\n\n");
|
||||
}
|
||||
else {
|
||||
if (wfiStatus.edge == INT_EDGE_FALLING)
|
||||
printf("waitForInterrupt: GPIO pin %d falling edge fired at %lld microseconds\n\n", wfiStatus.gpioPin, wfiStatus.timeStamp_us);
|
||||
else
|
||||
printf("waitForInterrupt: GPIO pin %d rising edge fired at %lld microseconds\n\n", wfiStatus.gpioPin, wfiStatus.timeStamp_us);
|
||||
}
|
||||
|
||||
printf("Testing IRQ @ GPIO%d on both edges and bouncetime %d microseconds. Toggle LED @ GPIO%d on IRQ.\n\n", IRQpin, BOUNCETIME, OUTpin);
|
||||
printf("To stop program hit return key\n\n");
|
||||
|
||||
wiringPiISR2(IRQpin, INT_EDGE_BOTH, &wfi, BOUNCETIME, NULL);
|
||||
|
||||
getc(stdin);
|
||||
|
||||
wiringPiISRStop (IRQpin);
|
||||
pinMode(OUTpin, INPUT);
|
||||
|
||||
return 0;
|
||||
}
|
||||
```
|
||||
|
||||
Ausgabe am Terminal:
|
||||
|
||||
```
|
||||
pi@RaspberryPi:~/wiringpi-test-v3.16 $ gcc -o isr_debounce isr_debounce.c -l wiringPi
|
||||
pi@RaspberryPi:~/wiringpi-test-v3.16 $ ./isr_debounce
|
||||
|
||||
ISR debounce test (WiringPi 3.16)
|
||||
|
||||
Testing waitForInterrupt on both edges IRQ @ GPIO16, timeout is 10000
|
||||
waitForInterrupt: GPIO pin 16 falling edge fired at 256522528012 microseconds
|
||||
|
||||
Testing IRQ @ GPIO16 on both edges and bouncetime 3000 microseconds. Toggle LED @ GPIO12 on IRQ.
|
||||
|
||||
To stop program hit return key
|
||||
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256522668010 microseconds, timenow = 256522668017, diff = 7
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256536364014 microseconds, timenow = 256536364021, diff = 7
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256536952011 microseconds, timenow = 256536952018, diff = 7
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256537856010 microseconds, timenow = 256537856016, diff = 6
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256538744011 microseconds, timenow = 256538744018, diff = 7
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256539664010 microseconds, timenow = 256539664017, diff = 7
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256540516010 microseconds, timenow = 256540516016, diff = 6
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256541560013 microseconds, timenow = 256541560022, diff = 9
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256542360010 microseconds, timenow = 256542360016, diff = 6
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256543320012 microseconds, timenow = 256543320020, diff = 8
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256544092021 microseconds, timenow = 256544092029, diff = 8
|
||||
^C
|
||||
pi@RaspberryPi:~/wiringpi-test-v3.16 $
|
||||
```
|
||||
|
||||
|
||||
## Hardware PWM (Pulsweitenmodulation)
|
||||
@@ -490,9 +690,21 @@ int fd = wiringPiI2CSetupInterface("/dev/i2c-1", 0x20);
|
||||
```
|
||||
|
||||
|
||||
### wiringPiI2CWrite / wiringPiI2CWriteReg8 / wiringPiI2CWriteReg16 / wiringPiI2CWriteBlockData
|
||||
### wiringPiI2CWrite
|
||||
|
||||
...
|
||||
Einfaches schreiben auf einen I2C-Slave. Manche Geräte benötigen keine Adressierung eines Registers.
|
||||
|
||||
### wiringPiI2CWriteReg8
|
||||
|
||||
Schreibt 8-Bit Daten auf ein Register am Geräte.
|
||||
|
||||
### wiringPiI2CWriteReg16
|
||||
|
||||
Schreibt 16-Bit Daten auf ein Register am Geräte.
|
||||
|
||||
### wiringPiI2CWriteBlockData
|
||||
|
||||
Schreibt entsprechend der angeben Größe Daten auf ein Register am Geräte.
|
||||
|
||||
### wiringPiI2CRawWrite
|
||||
|
||||
@@ -525,9 +737,25 @@ if (fd>0) {
|
||||
}
|
||||
```
|
||||
|
||||
### wiringPiI2CRead / wiringPiI2CReadReg8 / wiringPiI2CReadReg16 / wiringPiI2CReadBlockData
|
||||
|
||||
...
|
||||
### wiringPiI2CRead
|
||||
|
||||
Einfaches lesen vom I2C-Slave. Manche Geräte benötigen keine Adressierung eines Registers.
|
||||
|
||||
### wiringPiI2CReadReg8
|
||||
|
||||
Liest 8-Bit Daten vom Register am Geräte.
|
||||
|
||||
|
||||
### wiringPiI2CReadReg16
|
||||
|
||||
Liest 16-Bit Daten vom Register am Geräte.
|
||||
|
||||
|
||||
### wiringPiI2CReadBlockData
|
||||
|
||||
Liest entsprechend der angeben Größe Daten vom Register am Geräte.
|
||||
|
||||
|
||||
### wiringPiI2CRawRead
|
||||
|
||||
|
||||
@@ -4,42 +4,44 @@ The WiringPi-library enables access to the GPIO pins of the Raspberry Pi. In thi
|
||||
Since Version 3, extensions to the interface have been made again. In the case of new implementations, you should rely on the current / new functions.
|
||||
The old [GPIO Sysfs Interface for Userspace](https://www.kernel.org/doc/Documentation/gpio/sysfs.txt) is no longer supported.
|
||||
|
||||
**Attention:** This documentation is still in progress and therefore incomplete.
|
||||
The content of this documentation was created with care and to the best of our knowledge and belief. However, the authors do not guarantee the correctness, completeness and topicality of the information provided.The content of the documentation is used at your own risk.
|
||||
No liability is generally assumed for damage caused by material or intangible nature caused by the use or non-use of the information provided or by the use of incorrect and incomplete information.
|
||||
**Attention:**
|
||||
|
||||
This documentation is still in progress and therefore incomplete.
|
||||
The content of this documentation was created with care and to the best of our knowledge. However, the authors do not guarantee the correctness, completeness and topicality of the information provided.The content of the documentation is used at your own risk.
|
||||
|
||||
No liability is assumed for material or intangible damage caused by the use or non-use of the information provided or by the use of incorrect or incomplete information.
|
||||
|
||||
## Installation
|
||||
|
||||
Unfortunately, the WiringPi Library is not directly available in Raspberry Pi OS, so it must be installed manually. Either download a Debian package or create it manually.
|
||||
The WiringPi Library is not directly available in Raspberry Pi OS, so it must be installed manually. Either download a Debian package or create it manually.
|
||||
|
||||
**Create Debian package:**
|
||||
**Create Debian package:**
|
||||
|
||||
```bash
|
||||
sudo apt install git
|
||||
git clone https://github.com/WiringPi/WiringPi.git
|
||||
cd WiringPi
|
||||
./build debian
|
||||
mv debian-template/wiringpi-3.0-1.deb .
|
||||
mv debian-template/wiringpi_3.16_arm64.deb .
|
||||
```
|
||||
|
||||
**Install Debian package:**
|
||||
**Install Debian package:**
|
||||
|
||||
```bash
|
||||
sudo apt install ./wiringpi-3.0-1.deb
|
||||
sudo apt install ./wiringpi_3.16_arm64.deb
|
||||
```
|
||||
|
||||
**Uninstall Debian package:**
|
||||
**Uninstall Debian package:**
|
||||
|
||||
```bash
|
||||
sudo apt purge wiringpi
|
||||
```
|
||||
|
||||
|
||||
## PIN Numbering and Raspberry Pi Models
|
||||
|
||||
GPIOs: https://pinout.xyz/pinout/wiringpi
|
||||
GPIOs: [https://pinout.xyz/pinout/wiringpi](https://pinout.xyz/pinout/wiringpi)
|
||||
|
||||
**Raspberry Pi Models with 40-Pin GPIO J8 Header:**
|
||||
**Raspberry Pi Models with 40-Pin GPIO J8 Header:**
|
||||
|
||||
| BCM | WPI | Name | Physical | Name | WPI | BCM |
|
||||
|-----|-----|---------|:---------:|---------|-----|-----|
|
||||
@@ -64,8 +66,7 @@ GPIOs: https://pinout.xyz/pinout/wiringpi
|
||||
| 26 | 25 | GPIO.25 | 37 I 38 | GPIO.28 | 28 | 20 |
|
||||
| | | GND | 39 I 40 | GPIO.29 | 29 | 21 |
|
||||
|
||||
|
||||
**Raspberry Pi 1B Rev. 2 with 26-Pin GPIO P1 Header:**
|
||||
**Raspberry Pi 1B Rev. 2 with 26-Pin GPIO P1 Header:**
|
||||
|
||||
| BCM | WPI | Name | Physical | Name | WPI | BCM |
|
||||
|-----|-----|---------|:--------:|----------|-----|-----|
|
||||
@@ -83,9 +84,7 @@ GPIOs: https://pinout.xyz/pinout/wiringpi
|
||||
| 11 | 14 | SCLK | 23 I 24 | CE0 | 10 | 8 |
|
||||
| | | GND | 25 I 26 | CE1 | 11 | 7 |
|
||||
|
||||
|
||||
|
||||
**Raspberry Pi 1B Rev. 1 with 26-Pin GPIO P1 Header:**
|
||||
**Raspberry Pi 1B Rev. 1 with 26-Pin GPIO P1 Header:**
|
||||
|
||||
| BCM | WPI | Name | Physical | Name | WPI | BCM |
|
||||
|-----|-----|---------|:--------:|---------|-----|-----|
|
||||
@@ -103,41 +102,44 @@ GPIOs: https://pinout.xyz/pinout/wiringpi
|
||||
| 11 | 14 | SCLK | 23 I 24 | CE0 | 10 | 8 |
|
||||
| | | GND | 25 I 26 | CE1 | 11 | 7 |
|
||||
|
||||
|
||||
**References**
|
||||
|
||||
Note the different pin numbers and the I2C0 at Raspberry Pi 1B Rev. 1!
|
||||
|
||||
## Initialization
|
||||
|
||||
At the beginning, the WiringPi Library must be initialized.
|
||||
To do this, one of the following functions must be called up:
|
||||
|
||||
Outdated functions (no longer use):
|
||||
|
||||
``wiringPiSetup`` uses Wiringpi numbering (WPI) of the GPIO's and accesses the GPIO register directly.
|
||||
``wiringPiSetup`` uses WiringPi numbering (WPI) of the GPIOs and accesses the GPIO register directly.
|
||||
``wiringPiSetupGpio`` uses BCM numbering of the GPIOs and accesses the GPIO registers directly.
|
||||
``wiringPiSetupPhys`` uses physical PIN numbering of the GPIOs and accesses the GPIO register directly.
|
||||
``wiringPiSetupSys`` uses BCM numbering and calls the new function ``wiringPiSetupGpioDevice`` from version 3.4 to ensure compatibility with new core. In version 2, the virtual file system/SYS/Class/GPIO was used. However, the GPIO's exports had to take place externally before the initialization! The function is outdated and should not be used!
|
||||
``wiringPiSetupSys`` uses BCM numbering and calls the new function ``wiringPiSetupGpioDevice`` from version 3.4 to ensure compatibility with new core. In version 2, the virtual file system/SYS/Class/GPIO was used. However, the GPIOs exports had to take place externally before the initialization! The function is outdated and should not be used!
|
||||
|
||||
**Since Version 3.4:**
|
||||
``wiringPiSetupPinType`` decides whether WiringPi, BCM or physical PIN numbering is now used, based on the parameter pinType. So it combines the first 3 setup functions together.
|
||||
``wiringPiSetupGpioDevice`` is the successor to the ``wiringPiSetupSys`` function and now uses "GPIO Character Device Userspace API" in version 1 (from kernel 5.10). More information can be found at [docs.kernel.org/driver-api/gpio/driver.html](https://docs.kernel.org/driver-api/gpio/driver.html) on the parameter pintype, it is again decided which pin numbering is used.
|
||||
|
||||
``wiringPiSetupPinType`` decides whether WiringPi, BCM or physical pin numbering is used, based on the parameter pinType. So it combines the first 3 setup functions together.
|
||||
``wiringPiSetupGpioDevice`` is the successor to the ``wiringPiSetupSys`` function and now uses "GPIO Character Device Userspace API" in version 2 (WiringPi version 3.16 or higher). More information can be found at [docs.kernel.org/driver-api/gpio/driver.html](https://docs.kernel.org/driver-api/gpio/driver.html) on the parameter pintype, it is again decided which pin numbering is used.
|
||||
In this variant, there is no direct access to the GPIO memory (DMA) but rather through a kernel interface that is available with user permissions. The disadvantage is the limited functionality and low performance.
|
||||
|
||||
<!-- Attention code that uses the nine functions is no longer compatible with the older library version 2! -->
|
||||
|
||||
### wiringPiSetup V2 (outdated)
|
||||
|
||||
Inializating WiringPi in a classic way.
|
||||
>>>
|
||||
|
||||
**Notice:** This function is deprecated and should not be used in modern implementations.
|
||||
|
||||
```C
|
||||
int wiringPiSetupGpio(void)
|
||||
```
|
||||
int wiringPiSetupGpio(void);
|
||||
```
|
||||
|
||||
``Return Value``: Error status
|
||||
|
||||
> 0 ... No Error
|
||||
> 0 ... No Error
|
||||
|
||||
**Example:**
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
wiringPiSetupGpio();
|
||||
@@ -146,22 +148,23 @@ wiringPiSetupGpio();
|
||||
### wiringPiSetup V3
|
||||
|
||||
Initializing WiringPi.
|
||||
>>>
|
||||
|
||||
```C
|
||||
int wiringPiSetupPinType(enum WPIPinType pinType)
|
||||
int wiringPiSetupPinType(enum WPIPinType pinType);
|
||||
```
|
||||
|
||||
``pinType``: Type of PIN numbering...
|
||||
- `WPI_PIN_BCM` ... BCM-Numbering
|
||||
- `WPI_PIN_WPI` ... WiringPi-Numbering
|
||||
- `WPI_PIN_PHYS` ... Physical Numbering
|
||||
|
||||
- `WPI_PIN_BCM` ... BCM-Numbering
|
||||
- `WPI_PIN_WPI` ... WiringPi-Numbering
|
||||
- `WPI_PIN_PHYS` ... Physical Numbering
|
||||
|
||||
``Return Value``: Error status
|
||||
|
||||
> 0 ... No Error
|
||||
> -1 ... Invalid Parameter Error
|
||||
|
||||
**Example:**
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
wiringPiSetupPinType(WPI_PIN_BCM);
|
||||
@@ -172,13 +175,14 @@ wiringPiSetupPinType(WPI_PIN_BCM);
|
||||
### pinMode
|
||||
|
||||
Changes the mode of a GPIO pins.
|
||||
>>>
|
||||
|
||||
```C
|
||||
void pinMode(int pin, int mode)
|
||||
void pinMode(int pin, int mode);
|
||||
```
|
||||
|
||||
``Pin``: The desired PIN (BCM, Wiringpi or PIN number).
|
||||
``Mode``: The desired pin mode...
|
||||
|
||||
- `INPUT` ... Input
|
||||
- `OUTPUT` ... Output
|
||||
- `PWM_OUTPUT` ... PWM output (frequency and pulse break ratio can be configured)
|
||||
@@ -187,63 +191,71 @@ void pinMode(int pin, int mode)
|
||||
- `GPIO_CLOCK` ... Frequency output
|
||||
- `PM_OFF` ... Release
|
||||
|
||||
**Example:**
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
pinMode(17, OUTPUT);
|
||||
```
|
||||
|
||||
**Support:**
|
||||
`PM_OFF` resets the GPIO (Input) and releases it. PWM is stopped.
|
||||
Raspberry Pi 5 does not support the PWM Bal (Balanced) mode. The MS mode is activated at `PWM_OUTPUT`.
|
||||
`GPIO_CLOCK` is currently not yet supported in Raspberry Pi 5 (RP1).
|
||||
**Notice:**
|
||||
|
||||
- `PM_OFF` resets the GPIO (Input) and releases it. PWM is stopped.
|
||||
- Raspberry Pi 5 does not support the PWM Bal (Balanced) mode. The MS mode is activated at `PWM_OUTPUT`.
|
||||
- `GPIO_CLOCK` is currently not yet supported in Raspberry Pi 5 (RP1).
|
||||
|
||||
**PWM Exit**
|
||||
|
||||
`PWM_OUTPUT` Activates the specified PWM output with the settings:
|
||||
- Mode: BAL-Balanced (Pi0-4), MS-Mark/Space (Pi 5)
|
||||
- Range: 1024
|
||||
- Divider: 32
|
||||
|
||||
- Mode: BAL-Balanced (Pi0-4), MS-Mark/Space (Pi 5)
|
||||
- Range: 1024
|
||||
- Divider: 32
|
||||
|
||||
In order to make sure that the output starts without an active frequency, you should execute ``pwmWrite(PWM_GPIO, 0);`` before activating.
|
||||
After that, the corresponding clock and range values can be adapted, without a frequency already being output unintentionally.
|
||||
|
||||
### pinMode
|
||||
|
||||
### digitalWrite
|
||||
|
||||
Set the value of a GPIO pin.
|
||||
>>>
|
||||
Writes the value `HIGH` or `LOW` (1 or 0) to the given pin which must have been previously set as an output.
|
||||
|
||||
```C
|
||||
void digitalWrite(int pin, int value)
|
||||
void digitalWrite(int pin, int value);
|
||||
```
|
||||
|
||||
``pin``: The desired Pin (BCM-, Wiringpi- or PIN number).
|
||||
``value``: The logical value...
|
||||
- `HIGH` ... Value 1 (electrical ~ 3.3 V)
|
||||
- `LOW` ... Value 0 (electrical ~0 V / GND)
|
||||
|
||||
**Example:**
|
||||
- `HIGH` ... Value 1 (electrical ~3.3 V)
|
||||
- `LOW` ... Value 0 (electrical ~0 V / GND)
|
||||
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
pinMode(17, OUTPUT);
|
||||
DigitalWrite(17, HIGH);
|
||||
|
||||
digitalWrite(17, HIGH);
|
||||
```
|
||||
|
||||
**Note**
|
||||
|
||||
WiringPi treats any non-zero number as `HIGH`, however 0 is the only representation of `LOW`.
|
||||
|
||||
### pullUpDnControl
|
||||
|
||||
Changes the internal pull-up / pull-down resistance.
|
||||
>>>
|
||||
|
||||
```C
|
||||
void pullUpDnControl (int pin, int pud)
|
||||
void pullUpDnControl (int pin, int pud);
|
||||
```
|
||||
|
||||
``pin``: The desired Pin (BCM-, WiringPi-, or Pin-number).
|
||||
``pud``: The resistance type...
|
||||
- `PUD_OFF` ... No resistance
|
||||
- `PUD_UP` ... Pull-Up resistance (~50 kOhm)
|
||||
- `PUD_DOWN` ... Pull-Down resistance (~50 kOhm)
|
||||
|
||||
**Example:**
|
||||
- `PUD_OFF` ... No resistance
|
||||
- `PUD_UP` ... Pull-Up to pull to 3.3v (~50 kOhm resistance)
|
||||
- `PUD_DOWN` ... Pull-Down to pull to ground (~50 kOhm resistance)
|
||||
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
pullUpDnControl(17, PUD_DOWN);
|
||||
@@ -251,19 +263,19 @@ pullUpDnControl(17, PUD_DOWN);
|
||||
|
||||
### digitalRead
|
||||
|
||||
Reads the value of one GPIO-Pin.
|
||||
>>>
|
||||
Reads the value of the given GPIO-Pin. It will be `HIGH` or `LOW` (1 or 0) depending on the logic level at the pin.
|
||||
|
||||
```C
|
||||
int digitalRead(int pin)
|
||||
int digitalRead(int pin);
|
||||
```
|
||||
|
||||
``pin``: The desired Pin (BCM-, WiringPi-, or Pin-number).
|
||||
``Return Value``: The logical value.
|
||||
|
||||
> `HIGH` ... Value 1
|
||||
> `LOW` ... Value 0
|
||||
> `LOW` ... Value 0
|
||||
|
||||
**Example:**
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
pinMode(17, INPUT);
|
||||
@@ -281,36 +293,71 @@ if (value == HIGH)
|
||||
|
||||
### wiringPiISR
|
||||
|
||||
Registers an Interrupt Service Routine (ISR) / function that is executed on edge detection.
|
||||
Registers an Interrupt Service Routine (ISR) / function that is executed on edge detection.
|
||||
In this classic version, no parameters are passed to the ISR.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int wiringPiISR(int pin, int mode, void (*function)(void));
|
||||
```
|
||||
|
||||
``pin``: The desired Pin (BCM-, WiringPi-, or Pin-number).
|
||||
``mode``: Triggering edge mode...
|
||||
- `INT_EDGE_RISING` ... Rising edge
|
||||
- `INT_EDGE_FALLING` ... Falling edge
|
||||
- `INT_EDGE_BOTH` ... Rising and falling edge
|
||||
``pin``: The desired pin (BCM-, WiringPi-, or Pin-number).
|
||||
``mode``: Triggering edge mode
|
||||
|
||||
- `INT_EDGE_RISING` ... Rising edge
|
||||
- `INT_EDGE_FALLING` ... Falling edge
|
||||
- `INT_EDGE_BOTH` ... Rising and falling edge
|
||||
|
||||
``*function``: Function pointer for ISR
|
||||
``Return Value``:
|
||||
|
||||
> 0 ... Successful
|
||||
|
||||
> 0 ... Successful
|
||||
<!-- > <>0 ... Error not implemented at the moment. -->
|
||||
|
||||
For example see **wiringPiISRStop**.
|
||||
For example see [wiringPiISRStop](#wiringPiISRStop).
|
||||
|
||||
|
||||
### wiringPiISR2
|
||||
|
||||
Registers an Interrupt Service Routine (ISR) / function that is executed on edge detection.
|
||||
Extended parameters are passed to the ISR.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int wiringPiISR2(int pin, int edgeMode, void (*function)(struct WPIWfiStatus wfiStatus, void* userdata), unsigned long debounce_period_us, void* userdata);
|
||||
```
|
||||
|
||||
``pin``: The desired pin (BCM-, WiringPi-, or Pin-number).
|
||||
``edgeMode``: Triggering edge mode
|
||||
|
||||
- `INT_EDGE_RISING` ... Rising edge
|
||||
- `INT_EDGE_FALLING` ... Falling edge
|
||||
- `INT_EDGE_BOTH` ... Rising and falling edge
|
||||
|
||||
``*function``: Function pointer for ISR with the parameter struct WPIWfiStatus and a pointer.
|
||||
```C
|
||||
struct WPIWfiStatus {
|
||||
int statusOK; // -1: error (return of 'poll' command), 0: timeout, 1: irq processed, next data values are valid if needed
|
||||
unsigned int pinBCM; // gpio as BCM pin
|
||||
int edge; // INT_EDGE_FALLING or INT_EDGE_RISING
|
||||
long long int timeStamp_us; // time stamp in microseconds
|
||||
};
|
||||
```
|
||||
|
||||
``debounce_period_us``: Debounce time in microseconds, 0 disables debouncing.
|
||||
``userdata``: Pointer that is passed when calling the ISR.
|
||||
|
||||
``Return Value``:
|
||||
> 0 ... Successful
|
||||
|
||||
For example see [waitForInterrupt2](#waitForInterrupt2).
|
||||
|
||||
|
||||
### wiringPiISRStop
|
||||
|
||||
Deregisters the Interrupt Service Routine (ISR) on a Pin.
|
||||
Deregisters the Interrupt Service Routine (ISR) on a pin.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int wiringPiISRStop (int pin)
|
||||
int wiringPiISRStop (int pin);
|
||||
```
|
||||
|
||||
``pin``: The desired Pin (BCM-, WiringPi-, or Pin-number).
|
||||
@@ -320,8 +367,7 @@ int wiringPiISRStop (int pin)
|
||||
|
||||
<!-- > <>0 ... Error not implemented at the moment. -->
|
||||
|
||||
|
||||
**Example:**
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
static volatile int edgeCounter;
|
||||
@@ -334,43 +380,193 @@ int main (void) {
|
||||
wiringPiSetupPinType(WPI_PIN_BCM);
|
||||
edgeCounter = 0;
|
||||
|
||||
wiringPiISR (17, INT_EDGE_RISING, &isr);
|
||||
wiringPiISR(17, INT_EDGE_RISING, &isr);
|
||||
|
||||
Sleep(1000);
|
||||
printf("%d rinsing edges\n", );
|
||||
printf("%d rising edges\n", edgeCounter);
|
||||
|
||||
wiringPiISRStop(17);
|
||||
}
|
||||
```
|
||||
|
||||
|
||||
### waitForInterrupt
|
||||
|
||||
Waits for a previously defined interrupt (wiringPiISR) on the GPIO pin. This function should not be used.
|
||||
The function is no longer available, only ``waitForInterrupt2``!
|
||||
|
||||
|
||||
### waitForInterrupt2
|
||||
|
||||
Waits for a call to the Interrupt Service Routine (ISR) with a timeout and debounce time in microseconds. Blocks the program until the triggering edge occurs or the timeout expires.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int waitForInterrupt (int pin, int mS)
|
||||
struct WPIWfiStatus wfiStatus waitForInterrupt2(int pin, int edgeMode, int ms, unsigned long debounce_period_us)
|
||||
```
|
||||
|
||||
``pin``: The desired Pin (BCM-, WiringPi-, or Pin-number).
|
||||
``mS``: Timeout in milliseconds.
|
||||
``Return Value``: Error
|
||||
> 0 ... Successful
|
||||
> -1 ... GPIO Device Chip not successfully opened
|
||||
> -2 ... ISR was not registered (WiringPiISR must be called)
|
||||
``ms``: Timeout in milliseconds.
|
||||
- \-1 ... Wait without timeout
|
||||
- 0 ... No wait
|
||||
- 1-n ... Waits for a maximum of n milliseconds
|
||||
|
||||
``debounce_period_us``: Debounce time in microseconds, 0 disables debouncing.
|
||||
|
||||
``Return Value``:
|
||||
```C
|
||||
struct WPIWfiStatus {
|
||||
int statusOK; // -1: error (return of 'poll' command), 0: timeout, 1: irq processed, next data values are valid if needed
|
||||
unsigned int pinBCM; // gpio as BCM pin
|
||||
int edge; // INT_EDGE_FALLING or INT_EDGE_RISING
|
||||
long long int timeStamp_us; // time stamp in microseconds
|
||||
};
|
||||
```
|
||||
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
/*
|
||||
* isr_debounce.c:
|
||||
* Wait for Interrupt test program WiringPi >=3.16 - ISR2 method
|
||||
*
|
||||
*
|
||||
*/
|
||||
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
#include <errno.h>
|
||||
#include <stdlib.h>
|
||||
#include <unistd.h>
|
||||
#include <wiringPi.h>
|
||||
#include <time.h>
|
||||
|
||||
#define BOUNCETIME 3000 // microseconds
|
||||
#define BOUNCETIME_WFI 300
|
||||
#define TIMEOUT 10000
|
||||
//*************************************
|
||||
// BCM pins
|
||||
// IRQpin : setup as input with internal pullup. Connected with push button to GND with 1K resistor in series.
|
||||
// OUTpin : connected to a LED with 470 Ohm resistor in series to GND. Toggles LED with every push button pressed.
|
||||
//*************************************
|
||||
#define IRQpin 16
|
||||
#define OUTpin 12
|
||||
|
||||
int toggle = 0;
|
||||
|
||||
static void wfi(struct WPIWfiStatus wfiStatus, void* userdata) {
|
||||
// struct timeval now;
|
||||
long long int timenow, diff;
|
||||
struct timespec curr;
|
||||
char *edgeType;
|
||||
|
||||
if (clock_gettime(CLOCK_MONOTONIC, &curr) == -1) {
|
||||
printf("clock_gettime error");
|
||||
return;
|
||||
}
|
||||
|
||||
timenow = curr.tv_sec * 1000000LL + curr.tv_nsec/1000L; // convert to microseconds
|
||||
diff = timenow - wfiStatus.timeStamp_us;
|
||||
if (wfiStatus.edge == INT_EDGE_RISING)
|
||||
edgeType = "rising";
|
||||
else if (wfiStatus.edge == INT_EDGE_FALLING)
|
||||
edgeType = "falling";
|
||||
else
|
||||
edgeType = "none";
|
||||
printf("gpio BCM = %d, IRQ edge = %s, timestamp = %lld microseconds, timenow = %lld, diff = %lld\n", wfiStatus.gpioPin, edgeType, wfiStatus.timeStamp_us, timenow, diff);
|
||||
if (toggle == 0) {
|
||||
digitalWrite (OUTpin, HIGH);
|
||||
toggle = 1;
|
||||
}
|
||||
else {
|
||||
digitalWrite (OUTpin, LOW);
|
||||
toggle = 0;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
int main (void)
|
||||
{
|
||||
int major, minor;
|
||||
wiringPiVersion(&major, &minor);
|
||||
printf("\nISR debounce test (WiringPi %d.%d)\n\n", major, minor);
|
||||
|
||||
wiringPiSetupGpio();
|
||||
pinMode(IRQpin, INPUT);
|
||||
// pull up/down mode (PUD_OFF, PUD_UP, PUD_DOWN) => down
|
||||
pullUpDnControl(IRQpin, PUD_UP);
|
||||
pinMode(OUTpin, OUTPUT);
|
||||
digitalWrite (OUTpin, LOW) ;
|
||||
|
||||
printf("Testing waitForInterrupt on both edges IRQ @ GPIO%d, timeout is %d\n", IRQpin, TIMEOUT);
|
||||
struct WPIWfiStatus wfiStatus = waitForInterrupt2(IRQpin, INT_EDGE_BOTH, TIMEOUT, BOUNCETIME_WFI);
|
||||
if (wfiStatus.status < 0) {
|
||||
printf("waitForInterrupt returned error\n");
|
||||
pinMode(OUTpin, INPUT);
|
||||
return 0;
|
||||
}
|
||||
else if (wfiStatus.status == 0) {
|
||||
printf("waitForInterrupt timed out\n\n");
|
||||
}
|
||||
else {
|
||||
if (wfiStatus.edge == INT_EDGE_FALLING)
|
||||
printf("waitForInterrupt: GPIO pin %d falling edge fired at %lld microseconds\n\n", wfiStatus.gpioPin, wfiStatus.timeStamp_us);
|
||||
else
|
||||
printf("waitForInterrupt: GPIO pin %d rising edge fired at %lld microseconds\n\n", wfiStatus.gpioPin, wfiStatus.timeStamp_us);
|
||||
}
|
||||
|
||||
printf("Testing IRQ @ GPIO%d on both edges and bouncetime %d microseconds. Toggle LED @ GPIO%d on IRQ.\n\n", IRQpin, BOUNCETIME, OUTpin);
|
||||
printf("To stop program hit return key\n\n");
|
||||
|
||||
wiringPiISR2(IRQpin, INT_EDGE_BOTH, &wfi, BOUNCETIME, NULL);
|
||||
|
||||
getc(stdin);
|
||||
|
||||
wiringPiISRStop (IRQpin);
|
||||
pinMode(OUTpin, INPUT);
|
||||
|
||||
return 0;
|
||||
}
|
||||
```
|
||||
|
||||
Output on terminal:
|
||||
|
||||
```
|
||||
pi@RaspberryPi:~/wiringpi-test-v3.16 $ gcc -o isr_debounce isr_debounce.c -l wiringPi
|
||||
pi@RaspberryPi:~/wiringpi-test-v3.16 $ ./isr_debounce
|
||||
|
||||
ISR debounce test (WiringPi 3.16)
|
||||
|
||||
Testing waitForInterrupt on both edges IRQ @ GPIO16, timeout is 10000
|
||||
waitForInterrupt: GPIO pin 16 falling edge fired at 256522528012 microseconds
|
||||
|
||||
Testing IRQ @ GPIO16 on both edges and bouncetime 3000 microseconds. Toggle LED @ GPIO12 on IRQ.
|
||||
|
||||
To stop program hit return key
|
||||
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256522668010 microseconds, timenow = 256522668017, diff = 7
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256536364014 microseconds, timenow = 256536364021, diff = 7
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256536952011 microseconds, timenow = 256536952018, diff = 7
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256537856010 microseconds, timenow = 256537856016, diff = 6
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256538744011 microseconds, timenow = 256538744018, diff = 7
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256539664010 microseconds, timenow = 256539664017, diff = 7
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256540516010 microseconds, timenow = 256540516016, diff = 6
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256541560013 microseconds, timenow = 256541560022, diff = 9
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256542360010 microseconds, timenow = 256542360016, diff = 6
|
||||
gpio BCM = 16, IRQ edge = falling, timestamp = 256543320012 microseconds, timenow = 256543320020, diff = 8
|
||||
gpio BCM = 16, IRQ edge = rising, timestamp = 256544092021 microseconds, timenow = 256544092029, diff = 8
|
||||
^C
|
||||
pi@RaspberryPi:~/wiringpi-test-v3.16 $
|
||||
```
|
||||
|
||||
|
||||
## Hardware Pulse Width Modulation (PWM)
|
||||
|
||||
Available GPIOs: https://pinout.xyz/pinout/pwm
|
||||
Available GPIOs: [https://pinout.xyz/pinout/pwm](https://pinout.xyz/pinout/pwm)
|
||||
|
||||
### pwmWrite
|
||||
|
||||
Changes the PWM value of the pin. Possible values are 0 -> { PWM Range }.
|
||||
>>>
|
||||
|
||||
```C
|
||||
pwmWrite(int pin, int value)
|
||||
pwmWrite(int pin, int value);
|
||||
```
|
||||
|
||||
``pin``: The desired Pin (BCM-, WiringPi-, or Pin-number).
|
||||
@@ -381,9 +577,9 @@ pwmWrite(int pin, int value)
|
||||
Set the range for the PWM value of all PWM pins or PWM channels.
|
||||
19200 / divisor / range applies to the calculation of the PWM frequency (m/s mode).
|
||||
If ``pinMode(pin, PWM_OUTPUT)`` The value 1024 is automatically set for the divider.
|
||||
>>>
|
||||
|
||||
```C
|
||||
pwmSetRange (unsigned int range)
|
||||
pwmSetRange (unsigned int range);
|
||||
```
|
||||
|
||||
``range``: PWM Range
|
||||
@@ -391,60 +587,62 @@ pwmSetRange (unsigned int range)
|
||||
### pwmSetMode
|
||||
|
||||
Set the PWM mode for all PWM pins or PWM channels.
|
||||
>>>
|
||||
|
||||
```C
|
||||
pwmSetMode(int mode);
|
||||
```
|
||||
|
||||
``mode``: PWM Mode
|
||||
- `PWM_MODE_MS` ... Mark / Space Mode (PWM Fixed Frequency)
|
||||
- `PWM_MODE_BAL` ... Balanced Mode (PWM Variable Frequency)
|
||||
|
||||
**Support:**
|
||||
- `PWM_MODE_MS` ... Mark / Space Mode (PWM Fixed Frequency)
|
||||
- `PWM_MODE_BAL` ... Balanced Mode (PWM Variable Frequency)
|
||||
|
||||
**Notice:**
|
||||
|
||||
Raspberry Pi 5 does not support the balanced mode!
|
||||
|
||||
|
||||
### pwmSetClock
|
||||
|
||||
Set the divider for the basic PWM. The base clock is standardized for all Raspberry Pi's to 1900 kHz.
|
||||
19200 / divisor / range applies to the calculation of the PWM frequency (m/s mode).
|
||||
If ``pinmode(pin, PWM_OUTPUT)`` The value 32 is automatically set for the divider.
|
||||
>>>
|
||||
If ``pinMode(pin, PWM_OUTPUT)`` The value 32 is automatically set for the divider.
|
||||
|
||||
```C
|
||||
pwmSetClock(int divisor)
|
||||
pwmSetClock(int divisor);
|
||||
```
|
||||
|
||||
``divisor``: Divider (Raspberry Pi 4: 1-1456, all other 1-4095)
|
||||
``divisor``: Divider (Raspberry Pi 4: 1-1456, all other 1-4095)
|
||||
|
||||
- `0` ... Deactivates the PWM clock on Raspberry Pi 5, with other Pi's divisor `1` is used
|
||||
|
||||
**Support:**
|
||||
**Notice:**
|
||||
|
||||
Due to its higher internal basic clock, the Raspberry Pi 4 only has a setting range of `1 - 1456`.
|
||||
Otherwise, `0 - 4095` applies to a valid divider.
|
||||
|
||||
**Example:**
|
||||
**Example:**
|
||||
|
||||
```C
|
||||
int main (void) {
|
||||
wiringPiSetupGpio() ;
|
||||
wiringPiSetupGpio();
|
||||
|
||||
pwmSetRange(1024);
|
||||
pwmSetClock(35);
|
||||
|
||||
pwmWrite(18, 512);
|
||||
|
||||
|
||||
// Notice: PWM_BAL_OUTPUT NOT supported on Pi 5
|
||||
pinMode(18, PWM_MS_OUTPUT);
|
||||
|
||||
|
||||
double freq = 19200.0 / (double)pwmc / (double)pwmr;
|
||||
|
||||
|
||||
printf("PWM 50%% @ %g kHz", freq);
|
||||
delay(250);
|
||||
|
||||
|
||||
pinMode(18, PM_OFF);
|
||||
}
|
||||
```
|
||||
|
||||
|
||||
## I2C - Bus
|
||||
|
||||
``wiringPiI2CRawWrite`` and ``wiringPiI2CRawRead`` are the new functions in version 3 that now allow direct sending and reading of I2C data. The other write and read functions use the SMBus protocol, which is commonly used with I2C chips.
|
||||
@@ -453,18 +651,15 @@ int main (void) {
|
||||
|
||||
Open the default I2C bus on the Raspberry Pi and addresses the specified device / slave.
|
||||
|
||||
>>>
|
||||
```C
|
||||
wiringPiI2CSetup(const int devId)
|
||||
wiringPiI2CSetup(const int devId);
|
||||
```
|
||||
|
||||
``devId``: I2C-Gerät / Slave Adresse.
|
||||
``Return Value``: File Handle to I2C-Bus
|
||||
``devId``: I2C device / slave address.
|
||||
``Return Value``: File handle to I2C bus, or -1 on error.
|
||||
|
||||
> -1 ... Error or EXIT (Programm termination)
|
||||
**Example**
|
||||
|
||||
**Example**
|
||||
>>>
|
||||
```C
|
||||
int fd = wiringPiI2CSetup(0x20);
|
||||
```
|
||||
@@ -473,33 +668,41 @@ int fd = wiringPiI2CSetup(0x20);
|
||||
|
||||
Opens the specified I2C bus and addresses the specified I2C device / slave.
|
||||
|
||||
>>>
|
||||
```C
|
||||
wiringPiI2CSetupInterface(const char *device, int devId)
|
||||
wiringPiI2CSetupInterface(const char *device, int devId);
|
||||
```
|
||||
|
||||
``devId``: I2C-Gerät / Slave Adresse.
|
||||
``Return Value``: File Handle to I2C-Bus
|
||||
``devId``: I2C device / slave address.
|
||||
``Return Value``: File handle to I2C bus, or -1 on error.
|
||||
|
||||
> -1 ... Error or EXIT (Programm termination)
|
||||
**Example**
|
||||
|
||||
**Example**
|
||||
>>>
|
||||
```C
|
||||
int fd = wiringPiI2CSetupInterface("/dev/i2c-1", 0x20);
|
||||
```
|
||||
|
||||
### wiringPiI2CWrite
|
||||
|
||||
### wiringPiI2CWrite / wiringPiI2CWriteReg8 / wiringPiI2CWriteReg16 / wiringPiI2CWriteBlockData
|
||||
Simple device write. Some devices accept data this way without needing to access any internal registers.
|
||||
|
||||
...
|
||||
### wiringPiI2CWriteReg8
|
||||
|
||||
Writes 8-bit data value to the device register.
|
||||
|
||||
### wiringPiI2CWriteReg16
|
||||
|
||||
Writes 16-bit data value to the device register.
|
||||
|
||||
### wiringPiI2CWriteBlockData
|
||||
|
||||
Writes specified byte data values to the device register.
|
||||
|
||||
### wiringPiI2CRawWrite
|
||||
|
||||
Writing data about an I2C slave.
|
||||
>>>
|
||||
|
||||
```C
|
||||
int wiringPiI2CRawWrite(int fd, const uint8_t *values, uint8_t size)
|
||||
int wiringPiI2CRawWrite(int fd, const uint8_t *values, uint8_t size);
|
||||
```
|
||||
|
||||
``fd``: File Handle.
|
||||
@@ -507,8 +710,8 @@ int wiringPiI2CRawWrite(int fd, const uint8_t *values, uint8_t size)
|
||||
``size``: Number of bytes of the source buffer that should be written.
|
||||
``Return Value``: Number of bytes that were written.
|
||||
|
||||
**Example**
|
||||
>>>
|
||||
**Example**
|
||||
|
||||
```C
|
||||
int fd = wiringPiI2CSetup(I2C_ADDR);
|
||||
|
||||
@@ -527,16 +730,31 @@ else {
|
||||
}
|
||||
```
|
||||
|
||||
### wiringPiI2CRead / wiringPiI2CReadReg8 / wiringPiI2CReadReg16 / wiringPiI2CReadBlockData
|
||||
|
||||
...
|
||||
### wiringPiI2CRead
|
||||
|
||||
|
||||
Simple read from I2C slave. Some devices accept data this way without needing to access any internal registers.
|
||||
|
||||
### wiringPiI2CReadReg8
|
||||
|
||||
Reads 8-bit data value from the device register.
|
||||
|
||||
### wiringPiI2CReadReg16
|
||||
|
||||
Reads 16-bit data value from the device register.
|
||||
|
||||
|
||||
### wiringPiI2CReadBlockData
|
||||
|
||||
Reads specified byte data values from the device register.
|
||||
|
||||
### wiringPiI2CRawRead
|
||||
|
||||
Reading data from an I2C slave.
|
||||
>>>
|
||||
|
||||
```C
|
||||
int wiringPiI2CRawRead(int fd, uint8_t *values, uint8_t size)
|
||||
int wiringPiI2CRawRead(int fd, uint8_t *values, uint8_t size);
|
||||
```
|
||||
|
||||
``fd``: File Handle.
|
||||
@@ -544,8 +762,8 @@ int wiringPiI2CRawRead(int fd, uint8_t *values, uint8_t size)
|
||||
``size``: Number of bytes that are to be read into the target buffer.
|
||||
``Return Value``: Number of bytes that were read.
|
||||
|
||||
**Example**
|
||||
>>>
|
||||
**Example**
|
||||
|
||||
```C
|
||||
int fd = wiringPiI2CSetup(I2C_ADDR);
|
||||
|
||||
@@ -564,32 +782,30 @@ else {
|
||||
}
|
||||
```
|
||||
|
||||
|
||||
## SPI - Bus
|
||||
|
||||
Functions that start with ``wiringPiSPIx`` are new since version 3, allowing the SPI bus number to be specified. This is especially useful for the Compute Module, which has multiple SPI buses (0-7). The old functions remain available, but they always refer to SPI bus 0, which is available on the 40 pin GPIO connector.
|
||||
|
||||
|
||||
### wiringPiSPISetup / wiringPiSPISetupMode / wiringPiSPIxSetupMode
|
||||
|
||||
Opens the specified SPI bus.
|
||||
Opens the specified SPI bus. The Raspberry Pi has 2 channels, 0 and 1. The speed parameter is an integer in the range of 500,000 through 32,000,000 and represents the SPI clock speed in Hz.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int wiringPiSPISetup (int channel, int speed)
|
||||
int wiringPiSPISetupMode (int channel, int speed, int mode)
|
||||
int wiringPiSPIxSetupMode(const int number, const int channel, const int speed, const int mode)
|
||||
int wiringPiSPISetup (int channel, int speed);
|
||||
|
||||
int wiringPiSPISetupMode (int channel, int speed, int mode);
|
||||
|
||||
int wiringPiSPIxSetupMode(const int number, const int channel, const int speed, const int mode);
|
||||
```
|
||||
|
||||
``number``: SPI muber (typically 0, on Compute Module 0-7).
|
||||
``number``: SPI number (typically 0, on Compute Module 0-7).
|
||||
``channel``: SPI channel (typically 0 or 1, on Compute Module 0-3).
|
||||
``speed``: SPI clock.
|
||||
``mode``: SPI mode (https://www.kernel.org/doc/Documentation/spi/spidev).
|
||||
``Return Value``: File handle to the SPI bus
|
||||
> -1 ... Error or EXIT (Programm termination)
|
||||
``speed``: SPI clock speed in Hz (500,000 to 32,000,000).
|
||||
``mode``: SPI mode ([www.kernel.org/doc/Documentation/spi/spidev](https://www.kernel.org/doc/Documentation/spi/spidev)).
|
||||
``Return Value``: File handle to the SPI bus, or -1 on error.
|
||||
|
||||
**Example**
|
||||
|
||||
**Example**
|
||||
>>>
|
||||
```C
|
||||
const int spiChannel = 1;
|
||||
const int spiSpeedInit = 250000; // Hz
|
||||
@@ -604,25 +820,26 @@ if ((hSPI = wiringPiSPISetup (spiChannel, spiSpeed)) < 0) {
|
||||
wiringPiSPIClose(spiChannel);
|
||||
```
|
||||
|
||||
### wiringPiSPIDataRW / wiringPiSPIxDataRW
|
||||
### wiringPiSPIDataRW / wiringPiSPIxDataRW
|
||||
|
||||
A synchronous fullduplex write and read operation is performed on the opened SPI bus. In the process, the sent data is overwritten by the received data.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int wiringPiSPIDataRW (int channel, unsigned char *data, int len)
|
||||
int wiringPiSPIxDataRW (const int number, const int channel, unsigned char *data, const int len)
|
||||
int wiringPiSPIDataRW (int channel, unsigned char *data, int len);
|
||||
|
||||
int wiringPiSPIxDataRW (const int number, const int channel, unsigned char *data, const int len);
|
||||
```
|
||||
|
||||
``number``: SPI muber (typically 0, on Compute Module 0-7).
|
||||
``number``: SPI number (typically 0, on Compute Module 0-7).
|
||||
``channel``: SPI channel (typically 0 or 1, on Compute Module 0-3).
|
||||
``data``: Buffer
|
||||
``len``: Size of ``data`` buffer or data size.
|
||||
``Return Value``: Return Value of ``ioctl`` function (https://man7.org/linux/man-pages/man2/ioctl.2.html)
|
||||
<0 ... Error, see ``errno`` for error number.
|
||||
``Return Value``: Return Value of ``ioctl`` function ([https://man7.org/linux/man-pages/man2/ioctl.2.html](https://man7.org/linux/man-pages/man2/ioctl.2.html))
|
||||
|
||||
> 0 ... Error, see ``errno`` for error number.
|
||||
|
||||
**Example**
|
||||
|
||||
**Example**
|
||||
>>>
|
||||
```C
|
||||
const int spiChannel = 1;
|
||||
const int spiSpeedInit = 250000; // Hz
|
||||
@@ -637,8 +854,9 @@ int returnvalue;
|
||||
spiData[0] = 0b11010000;
|
||||
spiData[1] = 0;
|
||||
spiData[2] = 0;
|
||||
|
||||
returnvalue = wiringPiSPIxDataRW(0, spiChannel, spiData, 3);
|
||||
if (returnvalue<=0) {
|
||||
if (returnvalue <= 0) {
|
||||
printf("SPI transfer error: %d\n", errno);
|
||||
}
|
||||
|
||||
@@ -649,24 +867,25 @@ wiringPiSPIxClose(0, spiChannel);
|
||||
|
||||
Returns the file handle to the opened SPI bus.
|
||||
|
||||
>>>
|
||||
```C
|
||||
int wiringPiSPIGetFd(int channel)
|
||||
int wiringPiSPIxGetFd(const int number, int channel)
|
||||
int wiringPiSPIGetFd(int channel);
|
||||
|
||||
int wiringPiSPIxGetFd(const int number, int channel);
|
||||
```
|
||||
|
||||
``number``: SPI muber (typically 0, on Compute Module 0-7).
|
||||
``number``: SPI number (typically 0, on Compute Module 0-7).
|
||||
``channel``: SPI channel (typically 0 or 1, on Compute Module 0-3).
|
||||
``Return Value``: File handle to the SPI bus
|
||||
``Return Value``: File handle to the SPI bus
|
||||
|
||||
> -1 ... Invalid or not opened
|
||||
|
||||
**Example**
|
||||
>>>
|
||||
**Example**
|
||||
|
||||
```C
|
||||
const int spiChannel = 1;
|
||||
const int spiSpeedInit = 250000; // Hz
|
||||
int hSPI;
|
||||
|
||||
int hSPI;
|
||||
if ((hSPI = wiringPiSPISetup (spiChannel, spiSpeed)) < 0) {
|
||||
//error
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user