Raspberry Pi Forums

amcdonley

It appears that I can successfully pair, connect, and trust my PS3 Controller via bluetoothctl: sudo bluetoothctl [bluetoothctl]# pair <MAC> [CHG] Device <MAC> Connected: yes . . . [bluetooth]# connect <MAC> [CHG] Device <MAC> Connected: yes . . . [bluetooth]# trust <MAC> Changing <MAC> trust succe...

amcdonley

I have similar issue - WiFi Dongle address stops responding (ssh pi@X.0.0.X .. Host is down) and when I connect with WiFi built-in address X.0.0.Y, everything looks fine in ifconfig - up, no RX or TX errors. I'm wondering if the issue might be in my WiFi router (Xfinity SCIENTIFIC ATLANTA DPC3941T),...

amcdonley

You can get the current value with something like this: ... Thanks - I put your code into a file i2c_baudrate.sh (then chmod +x i2c_baudrate.sh): #!/bin/bash # Print current maximum i2c rate var="$(xxd /sys/class/i2c-adapter/i2c-1/of_node/clock-frequency | awk -F': ' '{print $2}')" var=${var//[[:bl...

amcdonley

You did set static ip in the Pi and dedicated ip in the router, correct?

Check the router log for events with the MAC address.

Did you try a stretch Os and don’t do an update? There may be some weird things from the 4.19 kernel.

amcdonley

I see that lots of people are having "XXX cutting off", where XXX:{aplay, espeak, espeak-ng, ...}, after updating Stretch to Linux 4.19.66-v7+ #1253 SMP Thu Aug 15 11:49:46 BST 2019 armv7l (and also some Buster folks). aplay /usr/share/sounds/alsa/Front_Center.wav cuts off at "Front Cen" in my case....

amcdonley

Interesting, so the CPU loads were 1.5%-2% yet temperature was high? PS/ Your link doesnt work well Thanks. Fixed the link. Not %. Load average is some weird number that seems to correspond to the number of cores in use when the number is less than the number of available cores. So 1.5 is an averag...

amcdonley

This is my analysis of motion detect on a “non-aspirated” Pi 3B Video Surveillance (TL:DR 10fps heat limited) My testing of “Recognition” such as faces, color and size, lane markings run around 1 FPS. All these are single threaded Python3 with “stock packaged” OpenCV. One multi-processing test resul...

amcdonley

I had aplay and espeak (text-to-speech) working great for the last year, until this week I executed the OS update sequence: sudo apt-get update sudo apt-get upgrade $ uname -a Linux Carl 4.19.66-v7+ #1253 SMP Thu Aug 15 11:49:46 BST 2019 armv7l GNU/Linux Now aplay is cutting off the last part of a w...

amcdonley

After updating my Raspbian Stretch: ``` Linux Carl 4.19.66-v7+ #1253 SMP Thu Aug 15 11:49:46 BST 2019 armv7l GNU/Linux ``` espeak stopped working completely for me. I got it to speak again by adding the following to my /home/pi/.bashrc ``` PA_ALSA_PLUGHW=1 export PA_ALSA_PLUGHW ``` (and rescanning i...

amcdonley

power a small servo like the SG90, from the 5v gpio pin , probably 200mA max, (Corrected) "GPIO 5v pin" means one of the two 5v pins on the GPIO connector. The SG90 can draw 600-700 mA stall and instantaneous which can sag the 5v supply in some cases. It would be advisable to add a small 5v switchi...

amcdonley

Designing for running while charging can be a challenge.

For reference: https://alanmcdonley.wixsite.com/curiou ... -Challenge

amcdonley

You should get a higher number of cycles with LiFePO4 cells. ... Some guys don't get enough for 24/7 from 30W ... It's a challenge.all right. The 8x NiMH AA cells fit in 4x4x1.25 inches and deliver 18-21 Watt-Hours (318mA idle * 9.6v nominal * 6 to 7 hours "fairly idle play time"). What allows 24/7...

amcdonley

A dc-dc buck converter ... charging equalizers ... PS It would be just as interesting to explain how the charger works mechanically and how the robot locates it and plugs in. Yes, powering my bot would need some combination of converters, equalizers AND UPS function. The total requirements / constr...

amcdonley

For more than 20 years I have wanted my robots to become independent - managing their own charging to allow 24/7 operation. This year, with a GoPiGo3 robot, I substantially achieved this goal, and have learned more about the challenges facing a 24/7 robot. Specifically, in my case, the capacity of N...

amcdonley

After reading I could save 25mA by turning off the HDMI interface on my RPi 3B robot, with the command "sudo /usr/bin/tvservice -o", I was expecting to see my robot enjoying an extra 20 minutes of idle playtime. It would appear to be less than 6 minutes, or perhaps nothing at all when no display is ...

amcdonley

For simple logging sensor data to a file and then plotting it, all local: 1) Log Battery Voltage and Plot on linear scale by hour of day, and by time since first measurement 2) Log PiCamera Brightness Value and Plot on log scale by hour of day It is also possible to tie sensor readings into the RPi-...

amcdonley

You may consider a generic messaging queue (eg mosquitto) to communicate state changes across processes. I have to admit I am intimidated by the whole IoT complexity. I've watched rosie the red robot as he ventured there, but I have kept my distance. After 40+ years of doing commercial software sys...

amcdonley

SQLite3 doesn't support multiple writers. You very rapidly destroy your database if you get two writers running. Use python multi-threading to run everything in a single python process. Results on my Pi3B using multiprocessing pool.map to 3 "worker/inserter" processes that each obtain closing_lock/...

amcdonley

Right now I have a python module to manage concurrent access to some robot variables stored in a file "carlData.json" carlDataJason.py : * saveCarlData(dataname, datavalue, logit=False) # adds datanaem:datavalue to carlData.json file * getCarlData(dataname=None) # either returns dictionary with all ...

amcdonley

That is samples per second, not bytes per second. So if each sample was 12 bytes (4 bytes each of X, Y, Z) then that would be 20,000 times 12 or 240,000 bytes per second. The top line is 1 byte per second, the bottom line slower for 5 bytes per second, which implies 12 bytes per second will be even...

amcdonley

Hey guys, ADXL355 digital accelerometer over SPI and would like to sample at 4000hz. Does the pi have a maximum sampling rate cap, According to How Fast Is SPI the Linux SPI driver (in a C language program) seems to max out around 20K bytes per second. I don't know how many bytes each ADXL355 sampl...

amcdonley

I think I see what happened - a few hours prior I did a: sudo rpi-clone sda and after it finished and unmounted both partitions, I unplugged the USB microSDcard adapter. Guess that did it. /var/log/messages: Aug 9 17:54:35 Carl kernel: [171141.137968] usb 1-1.4: USB disconnect, device number 5 Aug 9...

amcdonley

I just found my RPi 3B robot incommunicado by both wlan0 and wlan1 and this printed on the closed remote SSH login: packet_write_wait: Connection to 10.0.0.188 port 22: Broken pipe In spite of a solid blue light on the WiFi dongle, the RPI disk activity light seemed to indicate the bot was still run...

amcdonley

Would love a post project report and to see luminosity sensor code.

I want to use PiCamera (v1.3) to measure room light level over 24hr periods - don't need calibrated value, just continuous values from darkness to brightly lit.

amcdonley

You might be right but the question on the title I answered to was different than the one you are thinking at, since it did not had the "x, y heading" words at the end.. Kind of author changes its ckick-baity question then argues people gave him wrong answers, Please - I asked my question wrong, yo...

Search found 184 matches

PS3 Controller bluetooth "success" but no /dev/input/js0

Dongle not reachable, WiFi looks fine - was: How to auto reconnect wifi after signal lost

Re: Cannot determine i2c baud rate on rpi 3

Re: Odd WiFi Drop Out Issues

Where to report ALSA cutoff issue after Stretch update?

Re: Raspberry Pi model 3B video processing speed

Re: Raspberry Pi model 3B video processing speed

aplay and espeak issues after (Stretch) OS update

Re: espeak doesnt work

Re: How Many Sensors/Motors Can a Raspberry Pi 3 Handle at Once?

Re: Proyect: Autonomous robot with a rechargeable batteries

Re: Challenge of Powering Robot 24/7

Re: Challenge of Powering Robot 24/7

Challenge of Powering Robot 24/7

HDMI Off Power Saving Reality

Local: Data Logging, Plotting

Re: Simple Variable Sharing Between Python Processes?

Re: Simple Variable Sharing Between Python Processes?

Simple Variable Sharing Between Python Processes?

Re: Raspberry Pi High Frequency Sampling

Re: Raspberry Pi High Frequency Sampling

Re: RPi 3B WiFi Down - recovered by unplug, replug dongle

RPi 3B WiFi Down - recovered by unplug, replug dongle

PiCamera as Luminosity Sensor - Python Code Available?

Re: Agree? “IMU worthless for simple robots' x, y, heading?”