I2C

I have an EEPROM AT24C256. I want to write to this EEPROM from Timer Interrupt routine. But when I try, STM gets stuck. It's not going on for other code rows.

I have a text file of data that I want to extract a couple values from specific locations on specific lines.

I want witch /dev/i2c-1 device to be outside the SELinux security policy on Android 10.

I have the source code for Android 10. I tried creating a .te file in /device/thales/mt8768q/sepolicy/edgelab.te

In foo.te, I added a similar example to the site: https://source.android.com/security/selinux/customize.

In my Android 10 image I have the file (of type character) /dev/i2c-1:

crw ------- 1 root root 89, 1 2021-05-26 11:51 /dev/i2c-1

I have the source code for this Android and I would like this file to have read and write permission for any user, that is, it would be as follows:

crw-rw-rw- 1 root root 89, 1 2021-05-26 11:51 /dev/i2c-1

Otherwise, I have to run the chmod command every time the device is restarted.

I am new to FreeRTOS and have been reading the FreeRTOS documentation and writing simple code using FreeRTOS on an STM32F767 Nucleo Board. In the simple program that I wrote, I used Binary Semaphores only to signal certain tasks when LPTIM and GPIO interrupts occur through xSemaphoreGiveFromISR(), and to signal a different task to perform certain operations from another task through xSemaphoreGive().

Suppose that I have an I2C1 peripheral connected to two different equipments:

• An accelerometer that triggers a GPIO interrupt to the microcontroller whenever an activity/movement occurs. This GPIO interrupt signals the microcontroller that a piece of data inside its Interrupt Event registers must be read so that the next activity/movement event can be signalled again.
• An equipment that must be read from periodically, which will be triggered through an LPTIM or TIM peripheral

Can I use a Mutex and a Binary Semaphore in the situation above?

The Binary Semaphores will indicate to the task that an operation needs to be performed based on the respective interrupts that were triggered, but the Mutex will be shared between those two tasks, where Task1 will be responsible with reading data from the accelerometer, and Task2 will be responsible for reading data from the other equipment. I was thinking that a Mutex will be used since these two operations should never occur together, so that there are no overlapping I2C transactions that happen on the bus that could potentially lock up either of the I2C devices.

The code would look like the following:

I am currently using an SRF-10 sensor connected to an esp32. It's being powered by 5V and I am using a level converter to bring down the voltage to 3.3V to be able to use it on the esp32. Both the SCL and SDA have a 1.8K pull up resistor as recommended on the datasheet. I have written the following script to try to get a read from the sensor. I am not entirely sure if it is correct but soon as it reaches line 16 I get an error saying [Errno 19] ENODEV. Eveything I could find suggests that the i2c connection isn't working properly but when I run i2c.scan() it returns the sensor address so I am guessing connections aren´t the problem. My script is as follows:

I have my own FIFO class that works OK, but I'd like to extend its flexibility.

Right now, the data struct that goes in the FIFO is defined in the FIFO class, so every FIFO object has the same data struct.

It would be nice if every object could define its own FIFO struct and pass it to the FIFO class. The FIFO class shouldn't care what the structure looks like, it just queues and enqueues whatever struct got passed to the FIFO constructor. This is actually well beyond my current skill set, but I thought with a little help, maybe I could pull it off.

Here's a simple example of what I'm trying to do that I haven't been able to compile:

Here is the error message on git clone: