Difference between revisions of "RockpiS/dev/libmraa"

Revision as of 08:10, 23 April 2020

    ROCK Pi S >  Development >  Install Libmraa 

Libmraa on ROCK Pi S

This guide describes how to use libmraa on ROCK Pi S.

Install essential packages

Package libmraa is in the Radxa APT bionic-testing and buster-testing repositories.

Execute the following commands to add Radxa APT

rock@rockpis:~$ export DISTRO=bionic-testing      # for Bionic

or

rock@rockpis:~$ export DISTRO=buster-testing      # for Buster
rock@rockpis:~$ echo "deb http://apt.radxa.com/$DISTRO/ ${DISTRO%-*} main" | sudo tee -a /etc/apt/sources.list.d/apt-radxa-com.list

Get the pub key

rock@rockpis:~$  wget -O -  apt.radxa.com/buster-testing/public.key | sudo apt-key add -

Install essential packages:

rock@rockpis:~$ sudo apt-get update
rock@rockpis:~$ sudo apt-get install -y rockchip-overlay rockpis-dtbo libmraa # libmraa version: >=0.4
rock@rockpis:~$ sudo apt-get install -y linux-4.4-rockpis-latest # ROCK Pi S kernel version: >= 4.4.143-47

Enable interface

See ROCK Pi S GPIO pintout. ROCK Pi S has a 26-pin colorful expansion header. Each pin is distinguished by color. mraa define is shown below:

Hardware V12

16 GPIO:

   PIN03      GPIO2_A2
   PIN05      GPIO2_B0
   PIN07      GPIO2_B3
   PIN09      GPIO4_C4
   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
   PIN26      GPIO1_B2

3 I2C:

   PIN23      I2C0_SDA
   PIN24      I2C0_SCL
   PIN3       I2C1_SCL
   PIN5       I2C1_SDA
   PIN13      I2C3_SDA
   PIN15      I2C3_SCL
  

1 SPI:

   PIN19      SPI2TX        //must disable i2c0
   PIN21      SPI2RX        //must disable i2c0
   PIN23      SPI2CLK
   PIN24      SPI2CSN

3 UART:

   PIN8       UART0_TX
   PIN10      UART0_RX
   PIN23      UART1_TX
   PIN24      UART1_RX
   PIN19      UART2_RX
   PIN21      UART2_TX

2 PWM:

   PIN11      PWM2
   PIN13      PWM3

1 ADC:

   PIN26      ADC_IN0          //the measure voltage must lower than 1.8v

For those ROCK Pi S system images released after March 1st, 2020, to enable pwm2,pwm3,uart1,uart2,i2c0,i2c1,i2c3 and so overlays=, need to follow Device tree overlays.

For those ROCK Pi S system images released before March 1st, 2020, modify /boot/uEnv.txt to enable pwm2,pwm3,uart1,uart2,i2c0,i2c1,i2c3 for test.

rock@rockpis:~$ cat /boot/uEnv.txt
verbosity=7
overlay_prefix=rockchip
rootfstype=ext4
fdtfile=rockchip/rk3308-rock-pi-s.dtb
overlays=rk3308-console-on-uart0 rk3308-i2c0 rk3308-i2c1 rk3308-i2c3
rootuuid=37055840-4ec4-444f-979b-9e47ee4bd848
initrdsize=0x64d1d4
kernelversion=4.4.143-47-rockchip-g495ff574976c
initrdimg=initrd.img-4.4.143-47-rockchip-g495ff574976c
kernelimg=vmlinuz-4.4.143-47-rockchip-g495ff574976c

Test

Package libmraa provides some examples for testing spi, uart, i2c, gpio, etc. We way use the c files in /usr/local/share/mraa/examples/c.

And we copy them to home directory.

rock@rockpis:~/mraa-examples$ cp -av /usr/local/share/mraa/examples/c /home/rock/mraa-examples

You should pay more attention to the Black Bold words when modifying configuration file /boot/uEnv.txt.

test gpio

Use mraa-gpio tool to test

   root@rockpis:~# mraa-gpio list
   01         3V3: 
   02          5V: 
   03     I2C_SDA: GPIO I2C  
   04          5V: 
   05     I2C_SCL: GPIO I2C  
   06         GND: 
   07 I2S0_8CH_MC: GPIO 
   08    UART0_TX: GPIO UART 
   09         GND: 
   10    UART0_RX: GPIO UART 
   11 PWM2,I2C3_S: GPIO I2C  PWM  
   12 I2S0_8CH_SC: GPIO 
   13 PWM3,I2C3_S: GPIO I2C  PWM  
   14         GND: 
   15    SPDIF_TX: GPIO 
   16 I2S0_8CH_SD: GPIO 
   17         3V3: 
   18 I2S0_8CH_SD: GPIO 
   19 UART1_RTSN,: GPIO SPI  UART 
   20         GND: 
   21 UART1_CTSN,: GPIO SPI  UART 
   22 I2S0_8CH_LR: GPIO 
   23 UART1_RX,I2: GPIO I2C  SPI  UART 
   24 UART1_TX,I2: GPIO I2C  SPI  UART 
   25         GND: 
   26     ADC_IN0: AIO 
   root@rockpis:~# mraa-gpio set 15 1           #pin15 pull high
   root@rockpis:~# mraa-gpio set 15 0           #pin15 pull high

PWM test

ROCK Pi S V1.2 provides 2 PWM, PWM2 and PWM3. It is necessary to enable PWM1, PWM2 and PWM3 at the same time if you need PWM function.

Firstly, modify the /boot/uEnv.txt file to add the following

root@rockpis:~# cat /boot/uEnv.txt
verbosity=7
overlay_prefix=rockchip
rootfstype=ext4
fdtfile=rockchip/rk3308-rock-pi-s.dtb
overlays=rk3308-console-on-uart0 rk3308-pwm1 rk3308-pwm2 rk3308-pwm3
rootuuid=37055840-4ec4-444f-979b-9e47ee4bd848
initrdsize=0x64d1d4
kernelversion=4.4.143-47-rockchip-g495ff574976c
initrdimg=initrd.img-4.4.143-47-rockchip-g495ff574976c
kernelimg=vmlinuz-4.4.143-47-rockchip-g495ff574976c

Modify the macro PWM in /home/rock/mraa-examples/pwm.c as follows to test PWM2. To test PWM3, change #define PWM 11 to #define PWM 13.

/* PWM declaration */
#define PWM 11

Save and compile pwm.c

rock@rockpis:~/mraa-examples$ gcc -o pwm pwm.c -lmraa
rock@rockpis:~/mraa-examples$ sudo ./pwm 
PWM value is 0.010015
PWM value is 0.019985
PWM value is 0.030000
PWM value is 0.040014
PWM value is 0.049984
PWM value is 0.059999

I2C test

ROCK Pi S V1.2 provides 3 I2C,There are I2C0 ,I2C1, I2C3. If you need the I2C function, you can turn on one or more of them.

Firstly, modify the /boot/uEnv.txt file to add the following

root@rockpis:~# cat /boot/uEnv.txt
verbosity=7
overlay_prefix=rockchip
rootfstype=ext4
fdtfile=rockchip/rk3308-rock-pi-s.dtb
overlays=rk3308-console-on-uart0  rk3308-i2c0 rk3308-i2c1 rk3308-i2c3
rootuuid=37055840-4ec4-444f-979b-9e47ee4bd848
initrdsize=0x64d1d4
kernelversion=4.4.143-47-rockchip-g495ff574976c
initrdimg=initrd.img-4.4.143-47-rockchip-g495ff574976c
kernelimg=vmlinuz-4.4.143-47-rockchip-g495ff574976c

We use MPU6050 tets i2c. Modify the macro MPU6050 in /home/rock/mraa-examples/i2c_mpu6050.c ,as follows to test I2C0. To test I2C1 and I2C3, change #define I2C_BUS 0 to #define I2C_BUS 1 or#define I2C_BUS 3 .

  /* mraa header */
  #include "mraa/i2c.h"
  #define I2C_BUS 0
  

Save and compile pwm.c

rock@rockpis:~/mraa-examples$ gcc -o i2c_mpu6050 i2c_mpu6050.c  -lmraa
rock@rockpis:~/mraa-examples$ sudo ./i2c_mpu6050
accel: x:0 y:0 z:0
gyro: x:-10 y:1 z:7
  
accel: x:0 y:0 z:0
gyro: x:107 y:-12 z:69
   
accel: x:0 y:0 z:0
gyro: x:6 y:136 z:-50
   
accel: x:0 y:0 z:0
gyro: x:-5 y:48 z:-103
     
accel: x:0 y:0 z:0
gyro: x:3 y:3 z:5

UART test

ROCK Pi S V1.2 provides 3 UART,There are uart0 ,uart1, uart2. If you need the uatr function, you can turn on one or more of them.

Firstly, modify the /boot/uEnv.txt file to add the following

  root@rockpis:~# cat /boot/uEnv.txt 
  verbosity=7
  overlay_prefix=rockchip
  rootfstype=ext4
  fdtfile=rockchip/rk3308-rock-pi-s.dtb
  overlays=rk3308-uart0 rk3308-uart1 rk3308-uart2
  rootuuid=c3800af9-fa58-4fb3-bb56-e52fd04837ba
  initrdsize=0x5c96c3
  kernelversion=4.4.143-47-rockchip-g495ff574976c
  initrdimg=initrd.img-4.4.143-47-rockchip-g495ff574976c
  kernelimg=vmlinuz-4.4.143-47-rockchip-g495ff574976c

SPI test

Firstly, modify the /boot/uEnv.txt file.

root@rockpis:~# cat /boot/uEnv.txt
verbosity=7
overlay_prefix=rockchip
rootfstype=ext4
fdtfile=rockchip/rk3308-rock-pi-s.dtb
overlays=rk3308-console-on-uart0 rk3308-spi-spidev
param_spidev_spi_bus=2
rootuuid=37055840-4ec4-444f-979b-9e47ee4bd848
initrdsize=0x64d1d4
kernelversion=4.4.143-47-rockchip-g495ff574976c
initrdimg=initrd.img-4.4.143-47-rockchip-g495ff574976c
kernelimg=vmlinuz-4.4.143-47-rockchip-g495ff574976c

then execute command, sync, followed by reboot.

Create file test-spi.c and add the following contents.

  rock@rockpis:~/mraa-examples$ cat test-spi.c 
  #include <signal.h>
  #include <stdlib.h>
  #include <unistd.h>
  
  /* mraa header */
  #include "mraa/spi.h"
  
  /* SPI declaration */
  #define SPI_BUS 2
  
  /* SPI frequency in Hz */
  #define SPI_FREQ 10000000
  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;
      }
     
      j = 10;
      while(j) {
    	j--;
          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;
  }
  rock@rockpis:~/mraa-examples$ gcc -o test-spi test-spi.c -lmraa

Then short pin19 and pin21 and run test-spi

rock@rockpis:~/mraa-examples$ sudo ./test-spi 
0xaa
0xaa
0xaa
0xaa
0xaa
0xaa
0xaa
0xaa
0xaa
0xaa
MRAA: SUCCESS

ADC test

connect signal you want to measure, and then compile mraa example c file, aio.c, to test.

rock@rockpis:~/mraa-examples$ gcc aio aio.c -lmraa
rock@rockpis:~/mraa-examples$ sudo ./aio
ADC A0 read 1A5 - 421
ADC A0 read float - 0.41153
ADC A0 read 1A5 - 421
ADC A0 read float - 0.41153
ADC A0 read 1A5 - 421
ADC A0 read float - 0.41153
ADC A0 read 1A5 - 421
ADC A0 read float - 0.41153

Development

More introduction of libmraa can look at libmraa official website.

Troubleshooting

• Refer Troubleshooting page
• Post your issue on the forum: https://forum.radxa.com/c/rockpiS