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Why does pigpio not work on Raspberry Pi 4?
Thanks for your consideration. pigpio does not work on the Pi4B. At the moment I can’t get any information so do not know if this is a temporary blip or not. I need to find out what (if any) changes have been made to the memory map and SoC hardware peripherals (e.g. DMA, PWM, PCM, GPIO, SYST, BSC).
Is the I2C clock on Raspberry Pi 4 working?
As a side note, I’ve heard that the I2C clock stretching on the Raspberry Pi 4B (BCM2711) is working due to fixes in the silicon, so hopefully that’s correct and I’ll see if I can verify that, too. I’ve tried to use V69 on a PI4B (2GB) for using the pi as a i2c-slave (bscXfer/bsc_xfer).
Is there any reason to worry about the performance of pigpio?
Any reason to worry that there might be a degradation of performance/quality w.r.t PWM? pigpio currently defaults to primary channel 7, secondary channel 6 on the Pi4B. Without a detailed datasheet it’s pointless trying to guess why this is needed. The detailed datasheet should be made available to us within a couple of weeks from now.
Are there any peripherals that work with pigpio?
Most of the peripherals used by pigpio seem to work as before (PWM/PCM/GPIO/SYST/DMA). I haven’t tried SPI yet. The DMA channels which were free for pigpio use (14 primary, 6 secondary) do not operate quite as before.
How to change the PWM range on a GPIO?
The set_PWM_range function may be used to change the default range of 255. Return the PWM dutycycle in use on a GPIO. pi: >=0 (as returned by pigpio_start ). user_gpio: 0-31. Returns current PWM dutycycle if OK, otherwise PI_BAD_USER_GPIO or PI_NOT_PWM_GPIO.
How many PWM channels does a Raspberry Pi have?
Hardware PWM. The PWM controller on all variants of the Raspberry Pi has two independent channels. Each channel is available on multiple GPIOs (see section 9.5 on page 140 of BCM2835 ARM Peripherals): On a Raspberry Pi 3, GPIO12, GPIO13, GPIO18, and GPIO19 are broken out to the GPIO header.
How to pulse the led on a pigpio NPM?
Use PWM to pulse the LED connected to GPIO17 from fully off to fully on continuously. Turn the LED connected to GPIO17 on when the momentary push button connected to GPIO4 is pressed. Turn the LED off when the button is released. Continuously move a servo connected to GPIO10 clockwise and anti-clockwise.
How is the trigger function of a GPIO used?
The trigger function can be used to generate a pulse on a GPIO and alerts can be used to determine the time of a GPIO state change accurate to a few microseconds. These two features can be combined to measure distance using a HC-SR04 ultrasonic sensor.