# RT-Thread Peripherals
Author: Tang Cheuk Yu, Astral ([e-mail])

Board Schematic: https://gitlab.hkustracing.com/chleeay/internal_board
Core Board:
## Packages
We use the package system in rt-thread to install our custom libraries to drive the peripherals.

To install our packages,
1. go to https://github.com/LeeChunHei/custom_rtt_package_list
2. Download the files and place inside /env/packages
3. Change the directory name from custom_rtt_package_list to custom_packages
4. Edit the Kconfig file next to custom_packages (/env/packages/Kconfig), add a line

5. In VSCode, click RT-Thread Settings inside your project
    ![](https://i.imgur.com/vageNzJ.png)
6. Check all custom packages (under RT-Thread custom online packages/peripheral lib)
    ![](https://i.imgur.com/rsXjZZo.png)
7. Save and close the setting
8. In the terminal, enter ```pkgs --update```
    ![](https://i.imgur.com/fsyiyqp.png)

The packages will be installed after performing these steps, we can find the packages in the packages folder
![](https://i.imgur.com/u0WOoga.png)
If you can not find the folder, click reload

## Configure the packages
We need to configure the packages before using them
1. open RT-Thread Settings inside your project
2. In RT-Thread kernel
    - Tick frequency, Hz : 1000
3. RT-Thread custom online packages
    - peripheral libraries and drivers
        1. st7735r tft lcd driver package
            - Setup st7735r tft in menuconfig: Check
                1. SPI bus connected to the tft lcd: spi4
                2. GPIO port number for the chip select pin 2
                3. GPIO pin number for the chip select pin 0
                4. Adjustable backlight: Unchecked
                5. GPIO port number for the backlight pin 2
                6. GPIO pin number for the backlight pin 27
                7. GPIO port number for the dc pin 2
                8. GPIO pin number for the dc pin 20
                9. GPIO port number for the reset pin 2
                10. GPIO pin number for the reset pin 22
                11. Width of the tft lcd 128
                12. Height of the tft lcd 160
                13. Orientation of the tft lcd 0
        2. MT9V034 camera driver package
            - Enable auto explosure control: Check
            - Enable auto gain control: Check
            - HDR: 100dB
            - Width: 184
            - Height: 120
            - Camera configuration IC2/SCCB bus name: i2c10
            - Assert the program when faced configuration failure: Check
        3. Soft I2C driver package
            - Setup soft I2C in menuconfig: check
                1. Soft I2C bus name: i2c10
                2. Baudrate: 100000
                3. GPIO port number for the SCL pin: 3
                4. GPIO pin number for the SCL pin: 0
                5. GPIO port number for the SDA pin 3
                6. GPIO pin number for the SDA pin 1
                7. Use rt_hw_us_delay function: Check
4. Hardware Drivers Config
    - On-chip Peripheral Drivers
        1. Enable DMA: check
        2. Enable SPI: Check
            - Enable SPI4: check

## ST7735R LCD
Find the device

static rt_device_t lcd = rt_device_find("lcd0");

Start the device

rt_device_open(lcd,0);

for (rt_uint8_t y = 0; y < 120; ++y)
{
/* Set the TFT LCD rect region */
struct rt_st7735r_rect rect =
{
.x = 0,
.y = y,
.width = 120,
.height = 1,
};
rt_device_control(lcd, RT_ST7735R_SET_RECT, &rect);
/* Fill grayscale pxiels */
rt_uint8_t pixels[120];
rt_memset(pixels, y, 120);
rt_device_write(lcd,RT_ST7735R_WRITE_GRAYSCALE_PIXEL, pixels, 120);
}

For more details check the readme of the package

## MT9V034

int main(void)
{
/* Find the camera device */
rt_device_t cam = rt_device_find("MT9V034");
rt_device_open(cam, 0);

rt_uint8_t* buffer;
rt_size_t buffer_size;

while (1)
{
/* request a frame buffer */
buffer_size = rt_device_read(cam, 0, &buffer, 0);
if (buffer_size != 0)
{
/* Loop through the camera image */
for (rt_uint16_t i = 0; i < buffer_size; ++i)
{
/* Access one pixel in the frame */
buffer[i];
}
/* return the frame buffer back to queue */
rt_device_write(cam, 0, &buffer, 0);
}
else
{
rt_thread_mdelay(1);
}
}
}

## PWM
To enable pwm, go to rt-thread settings