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RockpiS/dev/libmraa

< RockpiS‎ | dev
Revision as of 08:37, 25 February 2020 by Zzl (Talk | contribs)

       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-rockpis is in the Radxa APT buster-testing repository. Edit file /etc/apt/sources.list.d/apt-radxa-com.list and add the following:

For Debian Buster

   deb http://apt.radxa.com/buster-testing/ buster main

Get the pub key

   wget -O -  apt.radxa.com/buster-testing/public.key | sudo apt-key add -

Install essential packages:

   sudo apt-get update
   sudo apt-get install -y rockchip-overlay rockpis-dtbo libmraa-rockpis

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 follow:

Hardware V10

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      I2C2_SDA
   PIN15      I2C2_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

modify /boot/hw_intfc.conf to enable pwm2,pwm3,uart1,uart2,i2c0,i2c1,i2c2 for test

   root@rockpis:/# cat boot/hw_intfc.conf
   # Hardware Interface Config
   # Set "on" to enable the optional hardware interfaces while set "off" to disable.
   
   intfc:i2c0=on
   intfc:i2c1=on
   intfc:i2c2=on
   intfc:i2c3=on
   
   intfc:pwm1=on
   intfc:pwm2=on
   intfc:pwm3=on
   
   intfc:spi0=off
   intfc:spi2=off
   
   intfc:uart0=on
   intfc:uart1=on
   intfc:uart2=on
   
  # Devicetree Overlay Enable, uncomment to enable .dtbo under /boot/overlays/.
  
  # Serial console on UART0
  intfc:dtoverlay=console-on-ttyS0
   
  # waveshare 3.5inch lcd (B v2) on SPI2. Need set:
  # intfc:uart1=off intfc:uart2=off intfc:i2c0=off intfc:spi2=on
  #intfc:dtoverlay=spi2-waveshare35b-v2
   
  # waveshare 3.5inch lcd (C) on SPI2. Need set:
  # intfc:uart1=off intfc:uart2=off intfc:i2c0=off intfc:spi2=on
  #intfc:dtoverlay=spi2-waveshare35c
  root@rockpis:/#

then reboot

Test

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
   root@rockpis:/#
test pwm

use c to test pwm.c,compile pwm.c

   root@rockpis:/home/rock/c# cat pwm.c
    #include <signal.h>
    #include <stdlib.h>
    #include <unistd.h>
   
   /* mraa header */
   #include "mraa/pwm.h"
   
   /* PWM declaration */
   #define PWM 11
   
   /* PWM period in us */
   #define PWM_FREQ 200
   
   volatile sig_atomic_t flag = 1;
   
   void
   sig_handler(int signum)
   {
       if (signum == SIGINT) {
           fprintf(stdout, "Exiting...\n");
           flag = 0;
       }
   }
   
   int
   main(void)
   {
       mraa_result_t status = MRAA_SUCCESS;
       mraa_pwm_context pwm;
       float value = 0.0f;
       float output;
    
       /* initialize mraa for the platform (not needed most of the times) */
       mraa_init();
    
       //! [Interesting]
       pwm = mraa_pwm_init(PWM);
       if (pwm == NULL) {
           fprintf(stderr, "Failed to initialize PWM\n");
           mraa_deinit();
           return EXIT_FAILURE;
       }
     
       /* set PWM period */
       status = mraa_pwm_period_us(pwm, PWM_FREQ);
       if (status != MRAA_SUCCESS) {
            goto err_exit;
       }
   
       /* enable PWM */
       status = mraa_pwm_enable(pwm, 1);
       if (status != MRAA_SUCCESS) {
           goto err_exit;
       }
   
       while (flag) {
           value = value + 0.01f;
   
           /* write PWM duty cyle */
           status = mraa_pwm_write(pwm, value);
           if (status != MRAA_SUCCESS) {
                goto err_exit;
           }
   
           usleep(50000);
    
           if (value >= 1.0f) {
               value = 0.0f;
           }
    
           /* read PWM duty cyle */
           output = mraa_pwm_read(pwm);
           fprintf(stdout, "PWM value is %f\n", output);
       }
    
       /* close PWM */
       mraa_pwm_close(pwm);
        
       //! [Interesting]
       /* deinitialize mraa for the platform (not needed most of the times) */
       mraa_deinit();
       
       return EXIT_SUCCESS;
        
   err_exit:
       mraa_result_print(status);
    
       /* close PWM */
       mraa_pwm_close(pwm);
        
       /* deinitialize mraa for the platform (not needed most of the times) */
       mraa_deinit();
    
       return EXIT_FAILURE;
   }
   
   root@rockpis:/home/rock/c# gcc pwm.c -lmraa
   root@rockpis:/home/rock/c#

Run the compiled file

   root@rockpis:/home/rock/c# ./a.out 
   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
   PWM value is 0.070014
   PWM value is 0.079984
   PWM value is 0.089999
   PWM value is 0.100014
   PWM value is 0.109983
test I2C
test uart
test spi
test adc

Development

More introduction of libmraa can look at libmraa official website.