When running under X, I can get information about the monitor connection as follows:
$ xrandr --verbose
DP-0.8 connected 2560x1440+2560+0 (0x1bd) normal (normal left inverted right x axis y axis) 597mm x 336mm
...
SignalFormat: DisplayPort
supported: DisplayPort
ConnectorType: DisplayPort
ConnectorNumber: 3
_ConnectorLocation: 3
non-desktop: 0
supported: 0, 1
2560x1440 (0x1bd) 241.500MHz +HSync -VSync *current +preferred
...
This information is available to applications via XRRListOutputProperties in #include <X11/extensions/Xrandr.h>
Is there an equivalent when running under Wayland? Specifically I need the information provided by ConnectorType and ConnectorNumber
Related
I want to add an INS to tf which will transform pointcloud from ORB SLAM2 to real world coordinate. My idea is to do a transformation so that the INS is at the rotational center of the robot.
My tf_tree looks like this: INS -> map -> base_link -> camera_link
My problem - despite the set transformation, the point cloud is saved in the orb slam system, not in the real coordinate system with INS. For my future work I have to get point cloud with world coordinates in ECEF.
(Ubuntu 18.04 with ROS Melodic and orb_slam2__ros)
What I made:
Between INS and map I made a broadcaster that reads the data from IMU (x,y,z,w) and transforms it to ROS msg.
transform_msg.header.frame_id = "INS"
transform_msg.child_frame_id = "map"
If I understand correctly, ORB SLAM2 transforms the point cloud from base_link to the map. (These parameters can be changed na file Node.cc na file .launch of camera in OS2)
Between base_link and camera_link I have a static_transform_publisher.
node pkg="tf2_ros" type="static_transform_publisher" name="gopro_offset" args="0 0 0 0 0 0 base_link camera_link" / include file="$(find orb_slam2_ros)/ros/launch/GOPRO.launch" /
I have a problem with my 5 inch resistive touch screen which I need to calibrate touch on Kivy app. My touch in Raspberry pi is correctly calibrated but when it comes to Kivy app it is not correct.
How can I calibrate the touch to get accurate touch in my Kivy app (GUI). I am using Raspberry pi 3 with Raspbian os (full version not lite) this.
Take a look at the configuration options for Kivy's mtdev input module: https://kivy.org/docs/api-kivy.input.providers.mtdev.html - in particular max_position_x, min_position_y, etc. From the documentation:
You can use a custom range for the X, Y and pressure values. On some drivers, the range reported is invalid. To fix that, you can add these options to the argument line:
invert_x : 1 to invert X axis
invert_y : 1 to invert Y axis
min_position_x : X minimum
max_position_x : X maximum
min_position_y : Y minimum
max_position_y : Y maximum
min_pressure : pressure minimum
max_pressure : pressure maximum
min_touch_major : width shape minimum
max_touch_major : width shape maximum
min_touch_minor : width shape minimum
max_touch_minor : height shape maximum
rotation : 0,90,180 or 270 to rotate
In ~/.kivy/config.ini, you should put something like this:
[input]
mtdev_%(name)s = probesysfs,provider=mtdev,max_position_x=12345,max_position_y=12345
This is if you're using mtdev, but you can also use hidinput from kernel 2.6.34 onwards. See also: https://kivy.readthedocs.io/en/master/api-kivy.input.providers.hidinput.html
Am running my ALSA Driver on Ubuntu 14.04, 64bit, 3.16.0-30-generic Kernel.
Hardware is proprietary hardware, hence cant give much details.
Following is the existing driver implementation:
Driver is provided sample format, sample rate, channel_count as input via module parameter. (Due to requirements need to provide inputs via module parameters)
Initial snd_pcm_hardware structure for playback path.
#define DEFAULT_PERIOD_SIZE (4096)
#define DEFAULT_NO_OF_PERIODS (1024)
static struct snd_pcm_hardware xxx_playback =
{
.info = SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_SYNC_START,
.formats = SNDRV_PCM_FMTBIT_S16_LE,
.rates = (SNDRV_PCM_RATE_8000 | \
SNDRV_PCM_RATE_16000 | \
SNDRV_PCM_RATE_48000 | \
SNDRV_PCM_RATE_96000),
.rate_min = 8000,
.rate_max = 96000,
.channels_min = 1,
.channels_max = 1,
.buffer_bytes_max = (DEFAULT_PERIOD_SIZE * DEFAULT_NO_OF_PERIODS),
.period_bytes_min = DEFAULT_PERIOD_SIZE,
.period_bytes_max = DEFAULT_PERIOD_SIZE,
.periods_min = DEFAULT_NO_OF_PERIODS,
.periods_max = DEFAULT_NO_OF_PERIODS,
};
Similar values for captures side snd_pcm_hardware structure.
Please, note that the following below values are replaced in playback open entry point, based on the current audio test configuration:
(user provides audio format, audio rate, ch count via module parameters as inputs to the driver, which are refilled in snd_pcm_hardware structure)
xxx_playback.formats = user_format_input
xxx_playback.rates = xxx_playback.rate_min, xxx_playback.rate_max = user_sample_rate_input
xxx_playback.channels_min = xxx_playback.channels_max = user_channel_input
Similarly values are re-filled for capture snd_pcm_hardware structure in capture open entry point.
Hardware is configured for clocks based on channel_count, format, sample_rate and driver registers successfully with ALSA layer
Found aplay/arecord working fine for channel_count = 1 or 2 or 4
During aplay/arecord, in driver when "runtime->channels" value is checked, it reflects the channel_count configured, which sounds correct to me.
Record data matches with played, since its a loop back test.
But when i use channel_count = 3, Both aplay or arecord reports
"Broken configuration for this PCM: no configurations available"!! for a wave file with channel_count '3'
ex: Playing WAVE './xxx.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 3
ALSA lib pcm_params.c:2162:(snd1_pcm_hw_refine_slave) Slave PCM not usable
aplay: set_params:1204: Broken configuration for this PCM: no configurations available
With Following changes I was able to move ahead a bit:
.........................
Method1:
Driver is provided channel_count '3' as input via module parameter
Modified Driver to fill snd_pcm_hardware structure as payback->channels_min = 2 & playback->channels_min = 3; Similar values for capture path
aplay/arecord reports as 'channel count not available', though the wave file in use has 3 channels
ex: aplay -D hw:CARD=xxx,DEV=0 ./xxx.wav Playing WAVE './xxx.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 3
aplay: set_params:1239: Channels count non available
Tried aplay/arecord with plughw, and aplay/arecord moved ahead
arecord -D plughw:CARD=xxx,DEV=0 -d 3 -f S16_LE -r 48000 -c 3 ./xxx_rec0.wav
aplay -D plughw:CARD=xxx,DEV=0 ./xxx.wav
Recording WAVE './xxx_rec0.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 3
Playing WAVE './xxx.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Channels 3
End of Test
During aplay/arecord, In driver when "runtime->channels" value is checked it returns value 2!!! But played wavefile has ch count 3...
When data in recorded file is checked its all silence
.........................
Method2:
Driver is provided channel_count '3' as input via module parameter
Modified Driver to fill snd_pcm_hardware structure as playback->channels_min = 3 & playback->channels_min = 4; Similar values for capture path
aplay/arecord reports as 'channel count not available', though the wave file in use has 3 channels
Tried aplay/arecord with plughw, and aplay/arecord moved ahead
During aplay/arecord, In driver when "runtime->channels" value is checked it returns value 4!!! But played wavefile has ch count 3...
When data in recorded file is checked its all silence
.........................
So from above observations, the runtime->channels is either 2 or 4, but never 3 channels was used by alsa stack though requested. When used Plughw, alsa is converting data to run under 2 or 4 channel.
Can anyone help why am unable to use channel count 3.
Will provide more information if needed.
Thanks in Advance.
A period (and the entire buffer) must contain an integral number of frames, i.e., you cannot have partial frames.
With three channels, one frame has six bytes. The fixed period size (4096) is not divisible by six without remainder.
Thanks CL.
I used period size 4092 for this particular test case with channel count 3, and was able to do loop back successfully (without using plughw).
One last question, when I used plughw earlier, and when runtime->channels was either 2 or 4, why was the recorded data not showing?
I tried to interface a RaspBerry pi with a LM335 temperature sensor this week-end. I'm using a MCP 3208 micro controller (channel 0) to interface the sensor. My goal is to collect samples data in SPI mode with python 3 scripts (classes).
I've checked the wiring and everything seems OK for me, I'but I'am a beginner, not really aware of Electronic concepts.
On the software side , I've installed quick2wire that claims to be python 3 compatible. In fact I want to lead the micro-controller with Python 3 API's (not thru shell calls)
Components
Raspberry pi REV2 model B with Rasbian-wheezy / Quick2wire installed. /dev/spix.y devices are listed.
MCP3208 ADC : 12 bits ADC / SPI. I'm using CS0 from the GPIO. The sensor is connected to channel 0 (B). see datasheet.
LM335 : temperature sensor. Outputs 10mV / °K. Min 5muA / Max 5 mA. It's connected to the MCP3208 channel #0 (A). see datasheet
220 ohms resistor (C). set up regarding LM335 outputs and desired temperature range coverage with my own calculations : May be a problem ...
Schematics extract
The LM335 (zener diode like) is connected as :
Wiring
Components are wired as shown bellow. Note that the yellow link is connected behind the cobbler kit on the CS0 SPI channel.
Quick2wire
I use the bellow script to query the CS0/Channel 0 GPIO interface. Unfortunately, I've not found usefull informations on the quick2wire-python-api API's. I've just copy/paste an example found as it was written in the same goal. I'm not sure if it really works :
#!/usr/bin/env python3
from quick2wire.spi import *
import sys, time
try:
channel = int(sys.argv[1])
except:
channel = 0
MCP3208 = SPIDevice(channel, 0)
while True:
try:
response = MCP3208.transaction(writing_bytes(0x41, 0x13), reading(1))
print ("output = %i" % ord(response[0]))
time.sleep(1)
except KeyboardInterrupt:
break
The script outputs :
output = 0
output = 0
output = 0
output = 0
output = 0
....
The result is the same with the channel 1 ( with argv = 1)
As the MCP3208 Din (probe output) receives voltage (see bellow) quick2wire should read at 18°C (rawghly my home inside temperature today)
3,3 V / 2^12 = 805 muA as I understand as "digital step"
18°C + 273°C = 291 => 2,91 V on the micro controller Din pin
and then return 2 910 / 0.805 = 3 615
Am I wrong ?
Controls
I've no oscilloscope, the only measures I can read are :
Voltage is 2.529 V at B checkpoint and 0,5 V (+/-5%) on the other MCP3208 channels
Note : the adjust pin is not used on the LM335 so results way not be accurate but voltage is here !
Seems to be a problem on the quick2wire side I think. But which ?
Code
The quick2wire.spi.SPIDevice class lakes of détails on the transfers parameter in terms of structure, content and output response format.
def transaction(self, *transfers):
"""
Perform an SPI I/O transaction.
Arguments:
*transfers -- SPI transfer requests created by one of the reading,
writing, writing_bytes, duplex or duplex_bytes
functions.
Returns: a list of byte sequences, one for each read or duplex
operation performed.
"""
transfer_count = len(transfers)
ioctl_arg = (spi_ioc_transfer*transfer_count)()
# populate array from transfers
for i, transfer in enumerate(transfers):
ioctl_arg[i] = transfers[i].to_spi_ioc_transfer()
ioctl(self.fd, SPI_IOC_MESSAGE(transfer_count), addressof(ioctl_arg))
return [transfer.to_read_bytes() for t in transfers if t.has_read_buf]
Another question :
how to set SPI configuration values like mode, clock speed, bits per word, LSB ... and so on.
Thanks in advance for your help.
I know you probably intend to learn how to use the ADC, an so this isn't really an answer to your question (I will use your very rich post for sure - thanks), but I'm aware of temperature sensors that already pack data in GPIO serial line, that are best suited for the raspberry.
You really have to read this awesome tutorial, if you haven't already.
I have 2 series in a file and I wish to lag one so that I can do a scatter plot?
Preferably, I would like to do this in a function like:
f(x,y) = x*(y-previous(y))
Is there a way to do this?
or even
plot "mydata.txt" u 3:(lagged($3))
Would help
Welcome to the XWin X Server
Vendor: The Cygwin/X Project
Release: 1.13.3.0
OS: CYGWIN_NT-6.1-WOW64 LskyHome2 1.7.17(0.262/5/3) 2012-10-19 14:39 i686
OS: Windows 7 Service Pack 1 [Windows NT 6.1 build 7601] (WoW64)
Package: version 1.13.3-1 built 2013-03-09
You can define a function:
lag(x) = ($0 == 0) ? (val1 = x, 0) : (val2 = val1, val1 = x, val1-val2)
This returns the difference between each point and the one before, and returns 0 if it is the first data point. $0 is the line-number pseudocolumn; functions can see columns from a datafile if they are called from within a plot command.
You can use it like
plot 'mydata.txt' u 3:(lag($3))