Libmraa-rockpi4 not found

Hardware and peripherals
10

Both for the tool i2cdetect and for Python 2.7 the bus 0 has to be addressed with its ID 7. Otherwise it works quite well. I connected the character OLED NHD-0420CW from Newhaven Display to I2C as a test.

linaro@rpi4b:~$ mraa-i2c list
Bus   0: id=07 type=linux  default
Bus   1: id=02 type=linux 
Bus   2: id=06 type=linux 
linaro@rpi4b:~$ sudo mraa-i2c detect 0
00: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
30: -- -- -- -- -- -- -- -- -- -- -- -- -- 3d -- -- 
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
70: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
linaro@rpi4b:~$ sudo i2cdetect -y 7
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- -- 
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
30: -- -- -- -- -- -- -- -- -- -- -- -- -- 3d -- -- 
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
70: -- -- -- -- -- -- -- --                         

#!/usr/bin/python
# -*- coding: utf-8 -*-
# Example lcd_showtime
# shows time and date in first tow rows of LCD
# Date: Dec 8th, 2017
# 

import os
from I2cCharDisplay import I2cCharDisplay
# import locale                                   # https://help.ubuntu.com/community/Locale
from time import strftime
import threading                                  # I do not like to use sleep(1) to wait a second, not even in an example

OLEDADDRESS =   0x3d                              # i2c address for the oled display
busnum = 7
# locale.setlocale(locale.LC_ALL,'de_DE.utf8')    # Set locale for a nice date, to date french girl, change to fr_FR.utf8

oled = I2cCharDisplay("OLED", OLEDADDRESS, 4)     # create an oled object for a 4 line display


def getCpuTemperature():
    tempFile = open( "/sys/class/thermal/thermal_zone0/temp" )
    cpu_temp = tempFile.read()
    tempFile.close()
    return float(cpu_temp)/1000


oled.clear()
oled.setBrightness(4)


def show_time():
    threading.Timer(1.0, show_time).start()         # Show time and date every second
    oled.cursorMove(col=7,row=1)
    oled.writeString(strftime('%H:%M:%S'))          # Hour:minute:second
    oled.cursorMove(col=3,row=2)
    oled.writeString(strftime('%a %d. %b %Y'))      # Weekday as locale’s abbreviated name, Day of the month,
                                                    # Month as locale’s abbreviated name, Year with century
    oled.cursorMove(col=4,row=3)
    oled.writeString("CPU temp ")
    oled.writeString(str(round(getCpuTemperature(), 1)))
    oled.writeString("C")

show_time()
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