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Difference between revisions of "Rockpi4/dev/libmraa"

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{{rockpi4_header}}
 
  
{{Languages|rockpi4/dev/libmraa}}
 
 
      [[rockpi4 | ROCK Pi 4]] > [[rockpi4/dev | Development]] > [[rockpi4/dev/libmraa  | Install Libmraa ]]
 
 
 
= Libmraa-rockpi4 =
 
 
Below is the instructions of how to install  '''libmraa'''.
 
 
== Install essential packages ==
 
 
Edit your /etc/apt/sources.list and add the following:
 
 
'''For Debian Stretch'''
 
 
    deb http://apt.radxa.com/stretch/ stretch main
 
 
'''For Ubuntu bionic'''
 
 
    deb http://apt.radxa.com/bionic/ bionic main
 
 
Get the pub key 
 
    wget -O -  apt.radxa.com/stretch/public.key | sudo apt-key add -
 
 
Update 
 
    sudo apt-get update && sudo apt-get upgrade
 
 
Install essential packages:
 
    sudo apt-get install -y rockchip-overlay && sudo apt-get install -y rockpi4-dtbo
 
 
== Install the latest u-boot and kernel (optional)==
 
    apt-get install rockpi4b-rk-u-boot-latest
 
 
Manually run the u-boot flash script
 
    /usr/local/sbin/rockpi4b_upgrade_bootloader.sh
 
 
 
Type '''YES''' to perform the uboot.img flashing.
 
 
then install kernel 
 
    apt-get install linux-base
 
    apt-get install linux-4.4-latest
 
 
 
After installation, check file '''/boot/extlinux/extlinux.conf'''. It lists all kernel version installed in ROCK Pi. The kernel corresponding to the first label is the newest version and the first boot option.
 
 
== Enable interface ==
 
See rockpi4 [[Rockpi4/hardware/rockpi4#gpio | GPIO pinout]],ROCK Pi 4 has a 40-pin expansion header. Each pin is distinguished by color. mraa define follow: 
 
 
27 GPIO:
 
    PIN03    GPIO2_A2
 
    PIN05    GPIO2_B0
 
    PIN07    GPIO2_B3
 
    PIN08    GPIO4_C4
 
    PIN10    GPIO4_C3
 
    PIN11    GPIO4_C2
 
    PIN12    GPIO4_A3
 
    PIN13    GPIO4_C6
 
    PIN15    GPIO4_C5
 
    PIN16    GPIO4_D2
 
    PIN18    GPIO4_D4
 
    PIN19    GPIO1_B0
 
    PIN21    GPIO1_A7
 
    PIN22    GPIO4_D5
 
    PIN23    GPIO1_B1
 
    PIN24    GPIO1_B2
 
    PIN27    GPIO2_A0
 
    PIN28    GPIO2_A1
 
    PIN29    GPIO2_B2
 
    PIN31    GPIO2_B1
 
    PIN32    GPIO3_C0
 
    PIN33    GPIO2_B4
 
    PIN35    GPIO4_A5
 
    PIN36    GPIO4_A4
 
    PIN37    GPIO4_D6
 
    PIN38    GPIO4_A6
 
    PIN40    GPIO4_A7
 
2 I2C:
 
    PIN3      I2C'''7'''_SDA
 
    PIN5      I2C'''7'''_SCL
 
    PIN27      I2C'''2'''_SCL
 
    PIN28      I2C'''2'''_SCL
 
    PIN29      I2C'''6'''_SCL
 
    PIN31      I2C'''6'''_SDA
 
2 SPI:
 
    PIN19      SPI'''1'''TX                    //'''must disable uart4'''
 
    PIN21      SPI'''1'''RX                    //'''must disable uart4'''
 
    PIN23      SPI'''1'''_CLK
 
    PIN24      SPI'''1'''_CS
 
    PIN29      SPI'''2'''TX                  //'''must disable i2c6'''
 
    PIN31      SPI'''2'''RX                  //'''must disable i2c6'''
 
    PIN7      SPI'''2'''_CLK
 
    PIN33      SPI'''2'''_CS 
 
1 UART:
 
    PIN8      UART'''2'''_TX
 
    PIN10      UART'''2'''_RX
 
    PIN19      UART'''4'''_TX
 
    PIN21      UART'''4'''_RX
 
2 PWM:
 
    PIN11      PWM'''0'''
 
    PIN13      PWM'''1'''
 
1 ADC:
 
    PIN13      ADC0      //the measure voltage must''' lower than 1.8v'''
 
 
modify '''/boot/hw_intfc.conf''' to enable '''pwm0,pwm1,uart2,uart4,i2c2,i2c6,i2c7''' for test
 
    root@localhost:/# cat boot/hw_intfc.conf
 
   
 
    # Hardware Interface Config
 
   
 
    # For more details, check https://wiki.radxa.com/Rockpi4/hardware/devtree_overlays.
 
   
 
    # '''Set "on" to enable the optional hardware interfaces while set "off" to disable.'''
 
   
 
    '''intfc:pwm0=off'''
 
    '''intfc:pwm1=off'''
 
    '''intfc:uart2=off'''
 
    '''intfc:uart4=off'''
 
    '''intfc:spi1=off'''
 
    '''intfc:spi2=off'''
 
    '''intfc:i2c2=off'''
 
    '''intfc:i2c6=off'''
 
    '''intfc:i2c7=off'''
 
   
 
    # '''Devicetree Overlay Enable, uncomment to enable .dtbo under /boot/overlays/.'''
 
   
 
    #intfc:dtoverlay=at24c02
 
    #intfc:dtoverlay=two-color-led
 
    #intfc:dtoverlay=console-on-ttyS2
 
    #intfc:dtoverlay=console-on-ttyS4
 
    #intfc:dtoverlay=devspi1
 
    #intfc:dtoverlay=devspi2
 
    root@localhost:/#
 
then '''reboot''' to make them effective
 
 
==Install libmraa==
 
 
    apt-get install libmraa
 
 
==Test==
 
===test gpio===
 
 
Use '''mraa-gpio''' tool to test 
 
 
    rock@localhost:~/mraa/build$ mraa-gpio list
 
    01        3V3:
 
    02          5V:
 
    03        SDA7: GPIO I2C 
 
    04          5V:
 
    05        SCL7: GPIO I2C 
 
    06        GND:
 
    07    SPI2_CLK: GPIO SPI 
 
    08        TXD2: GPIO UART
 
    09        GND:
 
    10        RXD2: GPIO UART
 
    11        PWM0: GPIO PWM 
 
    12    GPIO4_A3: GPIO
 
    13        PWM1: GPIO PWM 
 
    14        GND:
 
    15    GPIO4_C5: GPIO
 
    16    GPIO4_D2: GPIO
 
    17        3V3:
 
    18    GPIO4_D4: GPIO
 
    19 SPI1TX,TXD4: GPIO SPI  UART
 
    20        GND:
 
    21 SPI1RX,RXD4: GPIO SPI  UART
 
    22    GPIO4_D5: GPIO
 
    23    SPI1CLK: GPIO SPI 
 
    24      SPI1CS: GPIO SPI 
 
    25        GND:
 
    26    ADC_IN0: AIO 
 
    27        SDA2: GPIO I2C 
 
    28        SCL2: GPIO I2C 
 
    29 SCL6,SPI2RX: GPIO I2C  SPI 
 
    30        GND:
 
    31 SDA6,SPI2TX: GPIO I2C  SPI 
 
    32    GPIO3_C0: GPIO
 
    33      SPI2CS: GPIO SPI 
 
    34        GND:
 
    35    GPIO4_A5: GPIO
 
    36    GPIO4_A4: GPIO
 
    37    GPIO4_D6: GPIO
 
    38    GPIO4_A6: GPIO
 
    39        GND:
 
    40    GPIO4_A7: GPIO
 
    rock@localhost:~/mraa/build$
 
    rock@localhost:~/mraa/build$  sudo mraa-gpio set 40 1  //pin40 pull high                                                                                                                     
 
    rock@localhost:~/mraa/build$  sudo mraa-gpio set 40 0  //pin40 pull low
 
    root@localhost:~#
 
 
===test i2c===
 
Firstly, modify the /boot/hw_intfc.conf file as following and then reboot
 
# Hardware Interface Config
 
# For more details, check https://wiki.radxa.com/Rockpi4/hardware/devtree_overlays.
 
# Set "on" to enable the optional hardware interfaces while set "off" to disable
 
intfc:pwm0=off
 
intfc:pwm1=off
 
intfc:uart2=off
 
intfc:uart4=off
 
intfc:spi1=off
 
intfc:spi2=off
 
intfc:i2c2=on
 
intfc:i2c6=on
 
intfc:i2c7=on
 
 
 
Then, use '''mraa-i2c''' tool to test,we must have a i2c slave device,for example,we use I2C EEPROM:
 
    rock@localhost:~/mraa/build$ mraa-i2c list
 
    Bus  0: id=07 type=linux  default
 
    Bus  1: id=02 type=linux
 
    Bus  2: id=06 type=linux
 
    rock@localhost:~/mraa/build$ sudo mraa-i2c detect 0      //device on bus 0  //i2c7
 
    00: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
    10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
    20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
    30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
    40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
    50: 50 51 52 53 54 55 56 57 -- -- -- -- -- -- -- --
 
    60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
    70: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
 
    rock@localhost:~/mraa/build$ sudo mraa-i2c set 0 0x50 0x10 0x55  //write                                                                                                                         
 
    Device 50, Register = 10, Value = 55
 
    rock@localhost:~/mraa/build$ sudo mraa-i2c get 0 0x50 0x10              //read                                                                                             
 
    Register 0X10 = 0X55
 
 
===test spi===
 
fristly,modiy '''/boot/hw_intfc.conf''',if  use spi1,must disable uart4,if use spi2,disable i2c6.follow:
 
    rock@localhost:~/mraa/build$ cat /boot/hw_intfc.conf
 
   
 
    # Hardware Interface Config
 
   
 
    # For more details, check https://wiki.radxa.com/Rockpi4/hardware/devtree_overlays.
 
   
 
    # Set "on" to enable the optional hardware interfaces while set "off" to disable.
 
   
 
    intfc:pwm0=on
 
    intfc:pwm1=on
 
    intfc:uart2=on
 
    intfc:uart4='''off'''
 
    '''intfc:spi1=on
 
    '''intfc:spi2=on
 
    intfc:i2c2=on
 
    intfc:i2c6='''off'''
 
    intfc:i2c7=on
 
   
 
    # Devicetree Overlay Enable, uncomment to enable .dtbo under /boot/overlays/.
 
   
 
    #intfc:dtoverlay=at24c02
 
    #intfc:dtoverlay=two-color-led
 
    #intfc:dtoverlay=console-on-ttyS2
 
    #intfc:dtoverlay=console-on-ttyS4
 
    '''intfc:dtoverlay=devspi1'''          #spi1
 
    '''intfc:dtoverlay=devspi2'''        #spi2
 
 
If need debug console, you could uncomment '''intfc:dtoverlay=console-on-ttyS2'''
 
 
use '''c''' to test spi,compile spi.c,if use spi1,must disable
 
    root@localhost:~# cat spi.c
 
    #include <signal.h>
 
    #include <stdlib.h>
 
    #include <unistd.h>
 
   
 
    /* mraa header */
 
    #include "mraa/spi.h"
 
   
 
    /* SPI declaration */
 
    #define SPI_BUS 0
 
   
 
    /* SPI frequency in Hz */
 
    #define SPI_FREQ 400000
 
    int
 
    main(int argc, char** argv)
 
    {
 
        mraa_result_t status = MRAA_SUCCESS;
 
        mraa_spi_context spi;
 
        int i, j;
 
   
 
        /* initialize mraa for the platform (not needed most of the times) */
 
        mraa_init();
 
   
 
        //! [Interesting]
 
        /* initialize SPI bus */
 
        spi = mraa_spi_init(SPI_BUS);
 
        if (spi == NULL) {
 
            fprintf(stderr, "Failed to initialize SPI\n");
 
            mraa_deinit();
 
            return EXIT_FAILURE;
 
        }
 
   
 
        /* set SPI frequency */
 
        status = mraa_spi_frequency(spi, SPI_FREQ);
 
        if (status != MRAA_SUCCESS)
 
            goto err_exit;
 
   
 
        /* set big endian mode */
 
        status = mraa_spi_lsbmode(spi, 0);
 
        if (status != MRAA_SUCCESS) {
 
            goto err_exit;
 
        }
 
        while(1) {
 
            printf("0x%x\n",mraa_spi_write(spi, 0xaa));
 
        }
 
    err_exit:
 
        mraa_result_print(status);
 
   
 
        /* stop spi */
 
        mraa_spi_stop(spi);
 
   
 
        /* deinitialize mraa for the platform (not needed most of the times) */
 
        mraa_deinit();
 
   
 
        return EXIT_FAILURE;
 
    }
 
    root@localhost:~# gcc spi.c -lmraa
 
then short '''pin19''' and '''pin21''' and run a.out
 
    root@localhost:~# ./a.out
 
    0xaa
 
    0xaa
 
    ......
 
 
===test pwm===
 
 
for pwm python test,should install python and libpython2.7 
 
 
    apt-get install libpython2.7 python
 
 
use python script follow: 
 
 
    root@localhost:~# cat pwm.py
 
    #!/usr/bin/env python
 
    # Example Usage: Generates PWM at a step rate of 0.01 continuously.
 
    import mraa
 
    import time
 
   
 
    x = mraa.Pwm(11) # pin11 pwm0
 
    # x = mraa.Pwm(13) # pin13 pwm1
 
    x.period_us(700)
 
    x.enable(True)
 
   
 
    value= 0.0
 
   
 
    while True:
 
        x.write(value)
 
   
 
        time.sleep(0.05)
 
   
 
        value = value + 0.01
 
        if value >= 1:
 
            value = 0.0
 
    root@localhost:~#
 
 
then run pwm.py 
 
 
    root@localhost:~# ls
 
    pwm.py
 
    root@localhost:~# chmod +x pwm.py
 
    root@localhost:~# ./pwm.py
 
 
===test uart===
 
Disable console and enable uart2 and uart4 for uart test
 
    root@localhost:/# cat boot/hw_intfc.conf
 
   
 
    # Hardware Interface Config
 
   
 
    # For more details, check https://wiki.radxa.com/Rockpi4/hardware/devtree_overlays.
 
   
 
    # Set "on" to enable the optional hardware interfaces while set "off" to disable.
 
   
 
    intfc:pwm0=on
 
    intfc:pwm1=on
 
    '''intfc:uart2=on'''
 
    '''intfc:uart4=on'''
 
    intfc:spi1=on
 
    intfc:spi2=off
 
    intfc:i2c2=on
 
    intfc:i2c6=off
 
    intfc:i2c7=off
 
   
 
    # Devicetree Overlay Enable, uncomment to enable .dtbo under /boot/overlays/.
 
   
 
    #intfc:dtoverlay=at24c02
 
    #intfc:dtoverlay=two-color-led
 
    #intfc:dtoverlay=console-on-ttyS2
 
    #intfc:dtoverlay=console-on-ttyS4
 
    root@localhost:/#
 
then '''reboot'''. Connect your serial line to the corresponding serial port.
 
use ssh connect to rockpi4,we must have 2 windows(ssh and serial console ),one is for send data,anothor is for receive. 
 
 
send command follow:
 
    sudo mraa-uart dev 0 baud 1500000 send  data 
 
    or
 
    sudo mraa-uart dev 1 baud 1500000 send  data
 
receive command follow:
 
    sudo mraa-uart dev 0 baud 1500000 recv  1000
 
    or
 
    sudo mraa-uart dev 1 baud 1500000 recv  1000
 
 
the receive window will show the data
 
 
===test adc===
 
connect signal you want to measure,and then compile mraa examplec file to test.
 
    rock@localhost:~/mraa$ ls examples/c/aio.c
 
    examples/c/aio.c
 
    gcc examples/c/aio.c  -lmraa
 
 
then run a.out
 
 
==More examples==
 
 
More examples (including examples written in python and java) can be found  at:
 
 
/usr/local/share/mraa/examples/
 

Latest revision as of 01:53, 12 July 2023