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by rogerjames99
Mon Jul 01, 2019 10:06 am
Forum: Advanced users
Topic: Raspberry pi 3b+ as an SDR without the SDR
Replies: 1
Views: 167

Re: Raspberry pi 3b+ as an SDR without the SDR

Ooops.

Just realised that I was using outdated instructions from the mobisys2018_nexmon_software_defined_radio repository.. I will go back and look at the the instructions in the main nexmon repository and revert to my original plan of making therm work in a cross compilation environment.

Roger
by rogerjames99
Sun Jun 30, 2019 6:10 pm
Forum: Advanced users
Topic: Raspberry pi 3b+ as an SDR without the SDR
Replies: 1
Views: 167

Raspberry pi 3b+ as an SDR without the SDR

Has anyone tried this.. https://hackaday.com/2018/04/14/the-raspberry-pi-3b-as-an-sdr-without-the-sdr/ .. and had any meaningful success? I can get as far as building the replacement firmware. But I am struggling to build any the of the userspace and kernel stuff to actually make use of it! The prog...
by rogerjames99
Wed Apr 17, 2019 9:11 am
Forum: Raspbian
Topic: Spurious carriage return output to tty1 about 25/30 seconds after first login prompt following a boot
Replies: 4
Views: 287

Re: Spurious carriage return output to tty1 about 25/30 seconds after first login prompt following a boot

Thanks Trevor

Do you have any more pointers that help be find the bug report over at Debian.

Roger
by rogerjames99
Tue Apr 16, 2019 6:17 pm
Forum: Raspbian
Topic: Spurious carriage return output to tty1 about 25/30 seconds after first login prompt following a boot
Replies: 4
Views: 287

Spurious carriage return output to tty1 about 25/30 seconds after first login prompt following a boot

Has anyone else noticed this? On a pi not running any graphical desktop. Boot or reboot and watch the boot log rolling up the screen. At the end of the boot sequence a login prompt appears on the first virtual console (tty1). Wait for about 30 seconds and a spurious carriage return is output to the ...
by rogerjames99
Thu Oct 11, 2018 6:13 pm
Forum: Raspbian
Topic: Pi Zero W - wpa_supplicant - p2p-dev-wlan0 scanning stops connection to normal access point
Replies: 1
Views: 549

Re: Pi Zero W - wpa_supplicant - p2p-dev-wlan0 scanning stops connection to normal access point

EDITED!!! I did a rebuild and ran a new version of wpa_supplicant. This allowed the connection to proceed. This unfortunately triggered another problem that I have come across before. If you are trying to connect to any access point that has a short psk authentication timeout. For example support pr...
by rogerjames99
Mon Oct 08, 2018 3:29 pm
Forum: Raspbian
Topic: Pi Zero W - wpa_supplicant - p2p-dev-wlan0 scanning stops connection to normal access point
Replies: 1
Views: 549

Pi Zero W - wpa_supplicant - p2p-dev-wlan0 scanning stops connection to normal access point

Hi, I have been trying to get a Pi Zero W to connect to an access point at boot up. The configuration I use works well on a Pi 3 on board wifi. However when the same config is run on the Pi Zero W it fails to work. Examining what is going on using iw and wpa_cli it would seem that a scan has been st...
by rogerjames99
Fri Apr 27, 2018 6:07 pm
Forum: Troubleshooting
Topic: Unable to setup Wifi access point on raspbian stretch
Replies: 32
Views: 24227

Re: Unable to setup Wifi access point on raspbian stretch

The latest version of hostapd does net play well with wpa_supplicant on stretch. The simplest way to to fix this is to disable wpa_supplicant on the wireless interfaces you want to run hostapd on. You can do this by adding the following line to to the relevant wlan interface stanzas in /etc/dhcpcd.c...
by rogerjames99
Thu Feb 11, 2016 12:14 pm
Forum: HATs and other add-ons
Topic: Velleman VM205 oscilloscope and logic analyser board
Replies: 21
Views: 7083

Re: Velleman VM205 oscilloscope and logic analyser board

I suggest you try the code at https://github.com/Velleman/VM205/tree/master/src first and see if that works. If it does then it it is likely that your code or the wiringpi library is not initialising the spi bus or the velleman board properly. Have a look at the source and see who is not doing what....
by rogerjames99
Wed Sep 09, 2015 11:43 pm
Forum: HATs and other add-ons
Topic: Velleman VM205 oscilloscope and logic analyser board
Replies: 21
Views: 7083

Re: Velleman VM205 oscilloscope and logic analyser board

Have fun. I sure hope someone may find a solution for my question above... You need to ensure one device is using ce0 (p1-24) and the other ce1(p1-26). This will mean a combination of hardware jumpers (or maybe firmware) on both boards and corresponding config for the software for both boards to re...
by rogerjames99
Tue Jun 02, 2015 7:23 pm
Forum: HATs and other add-ons
Topic: Velleman VM205 oscilloscope and logic analyser board
Replies: 21
Views: 7083

Re: Velleman VM205 oscilloscope and logic analyser board

As far as I know there is only one version. The vm205 provides both single channel scope and ten channel logic analyser functionality.

Roger
by rogerjames99
Wed Apr 29, 2015 5:59 pm
Forum: HATs and other add-ons
Topic: Velleman VM205 oscilloscope and logic analyser board
Replies: 21
Views: 7083

Re: Velleman VM205 oscilloscope and logic analyser board

Arrived about a week ago. What a nice piece of kit! A single channel digital storage scope and 10 channel logic analyser for less than 30 quid! Using it to debug my initio robot and pirocon board. Contrary to some of the published info the software is written in c++ and runs as is on raspbian. Both ...
by rogerjames99
Sun Apr 26, 2015 5:09 pm
Forum: Camera board
Topic: RPi Cam Web Interface
Replies: 4984
Views: 1255639

Re: lockup in evening - watchdog did not fix it

If the lock ups are all on model As then it might be worth focussing on that. My model B systems seem super stable and I don't experience crashes. If the A runs out of run time memory then the watchdog is not going to help. It is worth trying the GPU memory reduction and MP4Box inline mode. The loc...
by rogerjames99
Sat Apr 25, 2015 3:10 pm
Forum: Camera board
Topic: RPi Cam Web Interface
Replies: 4984
Views: 1255639

Re: RPi Cam Web Interface

I am also seeing the same problem as @jbeale. In my case the the odd .h264 file was filing most of the disk and space errors were being logged. [2015/04/16 23:59:50] Purged 0 Files [2015/04/17 01:00:48] Scheduled management tasks [2015/04/17 01:00:48] Purged 0 Files [2015/04/17 02:01:47] Scheduled m...
by rogerjames99
Fri Apr 17, 2015 4:44 pm
Forum: HATs and other add-ons
Topic: Velleman VM205 oscilloscope and logic analyser board
Replies: 21
Views: 7083

Re: Velleman VM205 oscilloscope and logic analyser board

Latest update from ESR is that they have two pallets in transit which should arrive by the end of the month.

Roger
by rogerjames99
Fri Apr 17, 2015 12:39 am
Forum: HATs and other add-ons
Topic: Velleman VM205 oscilloscope and logic analyser board
Replies: 21
Views: 7083

Re: Velleman VM205 oscilloscope and logic analyser board

I have the module on order from ESR. They are the company behind both of the links above. They told me a couple of weeks ago that they where expecting the module in stock very soon. However I have not received anything yet. I was just wondering if anyone had got their hands on one, or knew anything ...
by rogerjames99
Thu Apr 16, 2015 4:29 pm
Forum: HATs and other add-ons
Topic: Velleman VM205 oscilloscope and logic analyser board
Replies: 21
Views: 7083

Velleman VM205 oscilloscope and logic analyser board

Hi,

Has anyone one got any recent information on when the Velleman VM205 oscilloscope and logic analyser board for the Raspberry Pi is going to ship. I have had one on order for a while. It looks like it has been "coming soon" since the middle of last year.

Roger
by rogerjames99
Mon Mar 16, 2015 7:00 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Sharing a DREQ between multiple DMA engines
Replies: 14
Views: 1900

Re: Sharing a DREQ between multiple DMA engines

Thanks, I thought that might be the case. It's working a lot better now. Just getting a bit confused about the length of the ticks. Are they still 1 millisecond? Oh and for posterity in the original test script I posted there was a bogus extra call to run_script that probably did not help things muc...
by rogerjames99
Mon Mar 16, 2015 5:05 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Sharing a DREQ between multiple DMA engines
Replies: 14
Views: 1900

Re: Sharing a DREQ between multiple DMA engines

Aha,

I was was looking for a callback function in the script language. Now I understand. Use a script to trigger the pulse on the pigiod host, and get callbacks via the socket on the client. That should reduce the cpu load in pigpiod which I suspect is the cause of the problems.

Thanks,

Roger
by rogerjames99
Mon Mar 16, 2015 3:53 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Sharing a DREQ between multiple DMA engines
Replies: 14
Views: 1900

Re: Sharing a DREQ between multiple DMA engines

files.zip Hi Joan, I think you are the author of pigpio. Is my guess correct? I was just about to send an email to [email protected].co.uk asking for some guidance. But I will ask here instead! I am currently struggling with latency problems when using pigpio to drive a ultrasonic range finder. The...
by rogerjames99
Mon Mar 16, 2015 10:16 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Sharing a DREQ between multiple DMA engines
Replies: 14
Views: 1900

Re: Sharing a DREQ between multiple DMA engines

I have given up on RPIO now and moved to pigpio. I have had much more success with this. As well as the problem with the clock source the pwm waveforms generated by RPIO would not drive some of the servos I had. These all work fine with pigpio. There are some features of RPIO and pigpio that I need ...
by rogerjames99
Sat Jan 24, 2015 11:53 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Sharing a DREQ between multiple DMA engines
Replies: 14
Views: 1900

Re: Sharing a DREQ between multiple DMA engines

Oops even got that wrong it was #camusdv
by rogerjames99
Sat Jan 24, 2015 6:47 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Sharing a DREQ between multiple DMA engines
Replies: 14
Views: 1900

Re: Sharing a DREQ between multiple DMA engines

Sorry forgot to credit #metachris with finding out about PCM.
by rogerjames99
Sat Jan 24, 2015 6:46 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Sharing a DREQ between multiple DMA engines
Replies: 14
Views: 1900

Re: Sharing a DREQ between multiple DMA engines

I have found out this that problem only occurs when using the PWM fifo as the DMA_REQ source. The timings are fine when using the PCM fifo as the DMA_REQ source (PWM.setup(delay_hw=PWM.DELAY_VIA_PCM)). I have attached three little scripts that can be used to show this problem without an oscilloscope...
by rogerjames99
Fri Jan 23, 2015 4:40 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Sharing a DREQ between multiple DMA engines
Replies: 14
Views: 1900

Re: Sharing a DREQ between multiple DMA engines

I initialised a third channel and the timings remained the same (double what they should be). This casts some doubt on my contention theory. Any ideas anyone? Can anyone else confirm the same behaviour? I am running the test on a B+ with the latest 3.12.35+ kernel. I cannot believe that the RPIO.PWM...

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