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Hi,
    I create some pins in the RT module, now I want to read and write pins' value in user space.I use the following code,but it failed.Is there any way to access RT module pins in the user space? The environment is Ubuntu20.04+xenomai3.1+linuxcnc2.9.Thanks!

---

    int compId;
    int ret;
    hal_float_t *pin_value;
    // init HAL
    compId = hal_init("user_program");
    if (compId < 0) {
        rtapi_print("HAL init failed\n");
        return -1;
    }
    pin_value = (hal_float_t*)hal_malloc(sizeof(hal_float_t));
    ret = hal_pin_float_new("kernel_pin", HAL_IN, &pin_value, compId);
    if (ret < 0) {
        rtapi_print("getting or creating pin failed!\n");
        hal_exit(compId);
        return -1;
    }

    ret = hal_link("user_program.kernel_pin", "ALT.I2600");
    if (ret < 0) {
        fprintf(stderr, "cann't bind signal!\n");
        hal_exit(compId);
        return -1;
    }
    hal_ready(compId);
    
    //*pin_value = 123.45;
    //rtapi_print("value is: %f\n", *pin_value);
    hal_exit(compId);

---

It prints some messages:
HAL: initializing hal_lib
HAL: initializing component 'user_program'
HAL: component 'user_program' initialized, ID = 28
smalloc_up: shmem available 1386552
HAL: ERROR: pin_new(kernel_pin) called with already-initialized memory
HAL: creating pin 'kernel_pin'
HAL: ERROR: data_ptr_addr not in shared memory

This card is not putting out any voltage to correct the position commanded vs position actual.. i think i might have a bad one

Homing my greatest bugbear. I simply can't get my head around this one.
I wish to have my new machine home X axis and Z axis using one pin IE pin 11
and the two Y axes  on pin 12.
I would prefer to have the Z axis home before the X.
The 2 Y axes should home together in whichever drive arrives first.
I have tried a number of things but have reverted to this setup.
Any help would be greatly appreciated.
Cheers Paul

The feature size is still well above a nanometer, but the edge precision and positioning precision have been well below a nanometer for many years.

The numbers quoted for various generations, such as TSMC's 4 nm are pure fiction; merely a label. Real dimensions have not been used as generation names for more than 20 years.

(I spent my career in state-of-the-art lithography. Now I use LinuxCNC to build model steam engines.)

Gene

Every reference to PINxx should be GPIOxx, which you see by reading the docs for hal_gpio.
If you need to use GPIO7 and GPIO8 you will need to disable SPI in /boot/broadcom/config.txt.
Also you may have to play around with the base thread to prevent rt errors.

linuxcnc.org/docs/devel/html/drivers/hal_gpio.html

Also loudly complain to byte2bot.

In the RPi sticky there is some info regarding hal_gpio and one or 2 other threads with working examples, not directly related to byte2bot but enough to see how it should work.

The Devs and other community members put hard work into the docs.