I am trying to stream audio from a Linux Mint Desktop to a RaspberryPi 3B running LibreELEC (Kodi) using PulseAudio RTP. I can successfully stream the audio with RTP multicast:
Desktop:
pactl load-module module-null-sink sink_name=rtp
pactl load-module module-rtp-send source=rtp.monitor
Pi:
pactl load-module module-rtp-recv latency_msec=50
But I would like to use RTP unicast to avoid UDP packet flooding associated with RTP multicast. This is what I have tried:
Desktop:
pactl load-module module-null-sink sink_name=rtp
pactl load-module module-rtp-send source=rtp.monitor destination_ip=192.168.1.117
Pi:
pactl load-module module-rtp-recv latency_msec=50
(I get "failed to load module" if I add 'sap_address=192.168.1.200')
No audio comes through the pi. Might someone know how to get the unicast working?
Simple fix:
pactl load-module module-rtp-recv latency_msec=50 sap_address=0.0.0.0
It now loads the "module-rtp-recv" module without an error and streams successfully
Related
My task is to develop an automation system for testing the device.
I have at my disposal:
raspberry pi(3b+/4)
modbus modules: icp con m - 7051D, m - 7055D, m-7061D, and few others.
At first I want to understand, how I can implement modbus protocol on RPi, how does it work.
In order to do that, I've used pymodbus library on RPi, which was working as an master, and modbusMAT on an PC, for recieving and decoding instructions from RPi. They were connected via rs-485 - USB adapter.
I've written some simple code, for writing a coil.
The RPi is communciating with PC, but the problem is, that the output, doesn't make sense to me.
Here's the code:
from pymodbus.client.sync import ModbusSerialClient as ModbusClient
client = ModbusClient(method = 'rtu', port='/dev/ttyUSB0', stopbits=1, bytesize = 8, parity='N', baurdrate = '9600', timeout=0.3)
connection = client.connect()
print (connection)
client.write_coils(1, 1, unit=0x01)
Screenshot from modbusMat console
The output:
[9C][84][8C][E4][FF]
[9C][08][8C][B4][FF]
[9C][84][8C][E4][FF]
[38][18][18][8C][CA]
The output is related to changes I've made parameters. From top to bottom:
address=1, values=1, unit=0x01
address=2, values=1, unit=0x01
address=1, values=2, unit=0x01
address=1, values=1, unit=0x02
How I understand is, that if I've set address to 1, then the addres byte on the console should be the same - [01], not [9C].
I've managed before to successfully send some instructions to the icp modules(turn on, turn off coil) from PC, via RS-485 but not from RPi.
I am writing a C program with the aim of configuring a peripheral device (the CS5368 ADC) via the I2C interface of a Dante Brooklyn II, a board based on a Microblaze soft-core processor running uClinux 2.4.
I have implemented the configuration following the Dante OEM docs for guidance, however when running my program I am encountering an "Operation not permitted" (EPERM) error when attempting to write data to I2C using i2c_smbus_write_byte_data.
Here is the section of code containing the culprit call to i2c_smbus_write_byte_data:
// Set ADC I2S to "Slave mode all speeds".
printf("Set the CS5368 I2S mode to slave\n");
unsigned char adc_dif = 0x01; // I2S mode
unsigned char adc_mode = 0x03; // Slave mode all speeds
unsigned char data = 0x90 | (adc_dif << 2) | adc_mode;
result = i2c_smbus_write_byte_data(i2c_fd, CS5368_GCTL_MDE, data);
if (result < 0) {
perror("Failed to write to the 'Global Mode Control' register");
return -1;
}
Here is the code within context of the full source of the small program. The program begins by resetting the CS5368 via a GPIO pin before doing the configuration via I2C.
EPERM is returned whether or not I have the CS5368 wired up. I've been able to successfully configure the CS5368 using the I2C interface of an Arduino Uno, so the issue does not appear to be related to the CS5368.
To run the program I login to the board via telnet as root, so I doubt the error has anything to do with user permissions.
The OEM docs state:
The Brooklyn II module can operate as an I2C controller running at
100Khz and using 7 bit addressing mode. It supports multi-master
operation. I2C devices can be accessed from user application running
on the Brooklyn II module. The interface supports the SMBus (System
Management Bus) protocol, which is a subset from the I2C protocol.
It goes on to list the supported i2c_smbus_* functions including i2c_smbus_write_byte_data, so the issue does not appear to be related to lack of support for SMBus or I2C.
I came across a related issue where a user was getting an EPERM error code when attempting to use the I2C write API, however the solution appears to have been to use the i2c_smbus_* API instead which I am already doing.
Any advice on what could be causing this error code to be returned or how to debug the issue further would be greatly appreciated!
Edit: In case it helps, here is the full output, starting from logging onto the board via telnet after having moved the exe to /tmp via ftp:
$ telnet 169.254.72.245
Trying 169.254.72.245...
Connected to 169.254.72.245.
Escape character is '^]'.
login: root
Password:
BusyBox v1.23.2 (2018-05-31 11:33:18 AEST) hush - the humble shell
/ # cd /tmp
/var/tmp # ./cs5368-i2c-config
Open GPIO device
Set GPIO tristate outputs
Set GPIO pins low
Sleep for 10 secs
Set GPIO pins high
Close GPIO file descriptor
Searching for I2C device
Opening /dev/i2c-0
Setting I2C_SLAVE 4c...
I2C Interface found: /dev/i2c-0
Set the CS5368 as the slave
Set the CS5368 I2S mode to slave
Failed to write to the 'Global Mode Control' register: Operation not permitted
I want to run simple example in arduino and send data from arduino to matlab for drawing plot,
my arduino code is following:
#include <SoftwareSerial.h>
int i=0;
void setup()
{
Serial.begin(9600);
}
void loop()
{
Serial.println(i);
i++;
}
and my matlab code is following:
arduino=serial('COM4','BaudRate',9600);
fopen(arduino)
x=linspace(1,100);
for i=1:length(x)
y(i)=instrfind(arduino);
y(i)=fscanf(arduino,'%d');
end
fclose(arduino);
disp('making plot..')
plot(x,y);
But I've faced with error! The following is matlab error:
Error using serial/fopen (line 72)
Open failed: Port: COM4 is not available. No ports
are available.
Use INSTRFIND to determine if other instrument
objects are connected to the requested device.
Error in kh (line 2)
fopen(Arduino)
and here is arduino error:
avrdude: ser_open(): can't open device "\\.\COM4": Access is denied.
My arduino uno (COM4) driver in device manager are installed.
I use matlab 2013a and ŮŽArduino 1.8.1 Genuino
How can I fix this error?
If you are using RS-232 for Arduino IDE/Monitor to communicate with your Arduino on COM4.
Since RS-232 is a point to point methodology, you can only have one program/device on each end unless you add a bunch of hijinks.
When you have the Arduino IDE/Monitor open it uses the com port and other programs are denied access.
I think you need to close the Arduino monitor program to release Com port 4 and then the Matlab program should be able to open the port.
PS : Test this using a terminal. Obviously the port needs to be open for the terminal to receive the arduino's prints. The terminal DOES open when you have the arduino ide open, but it DOES NOT open when the arduino's COM terminal is open. So theoretically, MATLAB shouldn't be having a problem when just the IDE is open.
This is how I solved the problem.
In device manager you will find the Arduino COM port.
Go to the Advance properties of the port
Set the COM port number to COM4
Then replug the USB.
I am currently working with building a Yocto Image for the RPi3 with the SenseHat installed.
The Yocto image consist of the following layers:
meta
meta-poky
meta-oe
meta-networking
meta-python
meta-raspberrypi
meta-java
an application-specific layer.
The application-specific layer is mainly tasked with loading the following kernel-modules:
i2c-dev
fb_sys_fops
syscopyarea
sysfillrect
sysimgblt
rpisense_core
rpisense_js
rpisense_fb
It also contains openssh, psplash, gcc, make, libiio, rtimulib and some other misc. packages.
My image boots nicely without the SenseHat mounted, but the boot-process stops before reaching the UART shell when it is mounted. It stays frozen until the system is reset by the watchdog.
Following is the last part of the UART output before the system freezes.
{...}
Populating dev cache
ALSA: Restoring mixer settings...
/usr/sbin/alsactl: load_state:1735: No soundcards found...
Tue Nov 1 10:01:54 UTC 2016
INIT: Entering runlevel: 5
Configuring network interfaces... [ 5.130327] smsc95xx 1-1.1:1.0 eth0: hardware isn't capable of remote wakeup
udhcpc (v1.24.1) started
Sending discover...
[ 6.662428] smsc95xx 1-1.1:1.0 eth0: link up, 100Mbps, full-duplex, lpa 0x4DE1
[ 6.688217] cfg80211: Calling CRDA to update world regulatory domain
Sending discover...
Sending select for 192.168.0.106...
Lease of 192.168.0.106 obtained, lease time 3600
/etc/udhcpc.d/50default: Adding DNS 192.168.0.20
/etc/udhcpc.d/50default: Adding DNS 192.168.0.40
done.
Starting system message bus: dbus.
Starting OpenBSD Secure Shell server: sshd
[ 9.034713] NET: Registered protocol family 10
done.
Starting rpcbind daemon...done.
Starting advanced power management daemon: No APM support in kernel
(failed.)
Starting bluetooth
bluetoothd
Starting syslogd/klogd: done
* Starting Avahi mDNS/DNS-SD Daemon: avahi-daemon
[ 9.401783] Bluetooth: Core ver 2.20
[ 9.405528] NET: Registered protocol family 31
[ 9.410088] Bluetooth: HCI device and connection manager initialized
[ 9.416576] Bluetooth: HCI socket layer initialized
[ 9.421576] Bluetooth: L2CAP socket layer initialized
[ 9.426747] Bluetooth: SCO socket layer initialized
...done.
Starting Telephony daemon
[ 9.507315] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[ 9.512765] Bluetooth: BNEP filters: protocol multicast
[ 9.518098] Bluetooth: BNEP socket layer initialized
Starting Linux NFC daemon
[ 9.624816] nfc: nfc_init: NFC Core ver 0.1
[ 9.629241] NET: Registered protocol family 39
I shoould note that I have soldered three wires onto the UART pins:
RPi3 UART pins http://www.embeddedforu.com/wp-content/uploads/2015/06/Raspberry-pi-UART-connections_thumb.png
When the system is frozen, I can still ping the device, but SSH does not work.
Any idea what might be causing this behavior?
It turned out that the problem lay within the yocto local.conf-file. The following line was set:
ENABLE_I2C = "1"
This created a second i2c-driver, which lead to one of the crashing on boot.
For any googlers out there: This flag does not need to be set. Instead make sure that the i2c-dev kernel driver is loaded at boot.
I never used the bluetooth, but it seems the system doesn't freeze, you just lose UART data when Bluetooth connects.
From here:
On the rpi3, it is normal since the BCM2837 on the Raspberry Pi3 has 2 UARTs (as did its predecessors), however to support the Bluetooth functionality the fully featured PL011 UART was moved from the header pins to the Bluetooth chip and the mini UART made available on header pins 8 & 10.
This has a number of consequences for users of the serial interface.
The /dev/ttyAMA0 previously used to access the UART now connects to Bluetooth.
I would advise you to try again having in config.txt
dtoverlay=pi3-disable-bt
enable_uart=1
And if you really need bluetooth, use
dtoverlay=pi3-miniuart-bt
And for the ssh, add "openssh" in your image recipe, and dependencies to connect like wpa-supplicant (don't forget to configure it)
I'm a new user on RTnet and try to make Rtnet work on Freescale Sabre Lite iMX6Q board. But I got an issue, RTnet can't use rt_fec.ko module driver to register rt_eth0 even though non real time driver is disable.
I'm using:
Linux kernel 3.0.43 download from Xenomai git://git.xenomai.org/ipipe-gch.git/?h=ipipe-3.0-imx6q
Xenomai 2.6 download from git.xenomai.org/xenomai-2.6.git/
RTnet 0.9.13 download from rtnet.org/download.html
Please see my kernel configuration and boot log in attached link.
Xenomai is loaded:
"*I-pipe: Domain Xenomai registered.
Xenomai: hal/arm started.
Xenomai: scheduling class idle registered.
Xenomai: scheduling class rt registered.
Xenomai: real-time nucleus v2.6.3 (Lies and Truths) loaded.
Xenomai: debug mode enabled.
Xenomai: starting native API services.
Xenomai: starting POSIX services.
Xenomai: starting RTDM services.* "
And FEC ethernet driver (non real-time driver) is loaded when kernel is booting
*"FEC Ethernet Driver
fec_enet_mii_bus: probed "*
Xenomai is built following install guideline for ARM platform from Xenomai:
http://xenomai.org/installing-xenomai-2-x/
RTnet is built by below command, because SABRE Lite use FEC ethernet card with Micrel KSZ9021 Gigabit chip so I put "--enable-fec" in configure command to build real-time driver for FEC ethernet card:
"./configure --host=armv7l-timesys-linux-gnueabi --with-rtext-config=/home/sonnguyen/rtnet-xenomai-rootfs/usr/xenomai/bin/xeno-config --with-linux=/home/sonnguyen/build/rtnet-xenomai-ipipe-imx6q --enable-rtcfg-dbg --enable-rtwlan --enable-net-routing --enable-router --enable-nomac --enable-rtcap --enable-proxy --enable-checks --enable-fec "
Then
"make DESTDIR=/home/sonnguyen/rtnet-xenomai-rootfs install"
I also changed RT_DRIVER from default value to "rt_fec" in rtnet.conf.
After kernel is booted, I ran "./rtnet start" and got this:
"RTnet: initialising real-time networking
RT FEC Ethernet Driver
./rtnet: line 385: can't create /sys/bus/pci/drivers/rt_fec/bind: nonexistent directory
initializing loopback...
RTnet: registered rtlo
RTcap: real-time capturing interface
ifconfig: SIOCGIFFLAGS: No such device
ifconfig: SIOCGIFFLAGS: No such device
RTcfg: init real-time configuration distribution protocol
RTmac: init realtime media access control
RTmac/TDMA: init time division multiple access control mechanism
ioctl: No such device
ioctl: No such device
ioctl: No such device
ioctl: No such device
ioctl (add): No such device
ioctl (add): No such device
ioctl (add): No such device
ifconfig: SIOCGIFFLAGS: No such device
Waiting for all slaves...ioctl: No such device
ioctl: No such device "
Then I tried:
"# lspci
lspci: /sys/bus/pci/devices: No such file or directory
ls /sys/bus/
ac97 hid mdio_bus platform sdio spi
event_source i2c mmc scsi serio usb "
No pci directory under /sys/bus/. Then I thought because the script can't find the ethernet physical bus, it can't register rteth0.
Then I looked into rtnet script and did some minor change. In the script it requires physical ethernet device ID (mentioned in REBIND_RT_NICS), so I tried to find out what it is and got this when make eth0 up with non real-time driver:
"eth0: Freescale FEC PHY driver [Micrel KSZ9021 Gigabit PHY] (mii_bus:phy_addr=1:06, irq=-1)
PHY: 1:06 - Link is Up - 1000/Full "
I think 1:06 is my physical bus ID, then I change the code in rtnet from:
for dev in $REBIND_RT_NICS; do
if [ -d /sys/bus/pci/devices/$dev/driver ]; then
echo $dev > /sys/bus/pci/devices/$dev/driver/unbind
fi
echo $dev > /sys/bus/pci/drivers/$RT_DRIVER/bind
done
To
echo 1:06 > /sys/bus/mdio_bus/drivers/Micrel\ KSZ9021\ Gigabit\ PHY/unbind
echo 1:06 > /sys/bus/platform/drivers/rt_fec/bind
And I tried again with "./rtnet start", this time I got this:
RTnet: initialising real-time networking
RT FEC Ethernet Driver
sh: write error: No such device
initializing loopback...
RTnet: registered rtlo
RTcap: real-time capturing interface
ifconfig: SIOCGIFFLAGS: No such device
ifconfig: SIOCGIFFLAGS: No such device
RTcfg: init real-time configuration distribution protocol
RTmac: init realtime media access control
RTmac/TDMA: init time division multiple access control mechanism
ioctl: No such device
ioctl: No such device
ioctl: No such device
ioctl: No such device
ioctl (add): No such device
ioctl (add): No such device
ioctl (add): No such device
ifconfig: SIOCGIFFLAGS: No such device
Waiting for all slaves...ioctl: No such device
ioctl: No such device
But it still said "No such device"
This is lsmod after I ran ./rtnet start
lsmod
Module Size Used by Not tainted
tdma 25691 0
rtmac 9724 1 tdma
rtcfg 58071 0
rtcap 7151 0
rt_loopback 1279 2
rtpacket 6365 0
rtudp 10738 0
rt_fec 12742 0
rtipv4 29987 2 rtcfg,rtudp
rtnet 40746 9 tdma,rtmac,rtcfg,rtcap,rt_loopback,rtpacket,rtudp,rt_fec,rtipv4
./rtifconfig
rtlo Medium: Local Loopback
IP address: 127.0.0.1
UP LOOPBACK RUNNING MTU: 1500
Only rtlo is registered.
I also tried with kernel linux without non real-time FEC driver (please refer in another config file in attached Skydrive link), but still the same issue happened.
Do you have any idea how to solve this issue? I did many search but still can not figure out how to fix it.
Because I can't attach the files to my post, so I put all of my configuration files in the link below:
https://onedrive.live.com/redir?resid=162EDF85AEBD2EFE!717&authkey=!AJ1Fjd_XiohUwes&ithint=file%2czip
Best Regards,
Nguyen Hung Son