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by SteveA
Mon Nov 25, 2019 11:19 am
Forum: Beginners
Topic: Adjust Screen Brightness programmatically x11 for HDMI and not LCD screens
Replies: 0
Views: 173

Adjust Screen Brightness programmatically x11 for HDMI and not LCD screens

I need to alter the screen brightness when a particular scientific project is run in a dark room/lab. The room is initially bright then turned dark when using such as UV, etc, and so the screen needs to be dimmed to match, so as still to be able to read the text/graphics. If the screen is not dimmed...
by SteveA
Wed Sep 18, 2019 3:39 pm
Forum: OpenVG
Topic: RPi 4 OpenVG Support?
Replies: 22
Views: 3731

Re: RPi 4 OpenVG Support?

I have just seen this post and have come across the same problem after buying a couple of RPI4 to start replacing the older RPI units in equipment. I use a derivative of A J Starks OpenVG library (runs over openvg) and unfortunately all projects have now come to a complete standstill. All applicatio...
by SteveA
Fri Sep 14, 2018 12:44 pm
Forum: Beginners
Topic: SAMBA - how to create multiple users without them being RPi users
Replies: 3
Views: 831

Re: SAMBA - how to create multiple users without them being RPi users

Thanks DirkS, it works a treat. I can now create multiple RPI users without them being able to login to the RPI and without them having a home folder.

Much appreciated
Steve
by SteveA
Tue Sep 11, 2018 4:17 pm
Forum: Beginners
Topic: SAMBA - how to create multiple users without them being RPi users
Replies: 3
Views: 831

SAMBA - how to create multiple users without them being RPi users

I can set the Raspberry Pi to samba share a specific folder for any user without any password and this works well. However I want to do the following I have not found a method to do this: 1. I need to have a common folder which I want to share. 2. I need 5 users to be able to login, each with a uniq...
by SteveA
Wed Nov 15, 2017 1:12 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: More than 2 SPI slaves
Replies: 19
Views: 10715

Re: More than 2 SPI slaves

Peter, from your original post, would you mind letting me know how you can disable the kernel from toggling CE0 or CE1 when using SPI because if that is what I have been trying to find out,
Thanks in advance
Steve
by SteveA
Thu Jan 05, 2017 8:36 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Chronodot with rtc-ds1307 Read Error
Replies: 4
Views: 3524

Re: Chronodot with rtc-ds1307 Read Error

Are you talking about this post or my reference to my recent post? Yes I am serious. And yes, I have followed the most recent methods of installing an RTC on Jessie. The RTC works fine, everytime, everyday, etc, until there is just one other access on the i2c to use such as a DAC, after which the RT...
by SteveA
Wed Jan 04, 2017 11:02 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Chronodot with rtc-ds1307 Read Error
Replies: 4
Views: 3524

Re: Chronodot with rtc-ds1307 Read Error

I have the same/similar problems and have spent many weeks trying to resolve it without success. I made a post at: https://www.raspberrypi.org/forums/viewtopic.php?f=33&t=169833&p=1090515#p1090515 which explains my problem. I have gone back on all of the forums posts I can find and see that it is a ...
by SteveA
Sun Jan 01, 2017 7:03 pm
Forum: C/C++
Topic: Writing system date/time to I2C RTC
Replies: 0
Views: 997

Writing system date/time to I2C RTC

Within my C program, the user needs to change the system date and time. It cannot be done in the shell in this instance as the user will not have access to a terminal command line. (for info, within my program I change the system time to that as wanted by the user by setting the time values in struc...
by SteveA
Fri Dec 23, 2016 7:13 pm
Forum: Advanced users
Topic: PWM on raspberry pi 3
Replies: 7
Views: 9753

Re: PWM on raspberry pi 3

I have exactly the same problem as per smufdwag, the original poster. The example PWM code as supplied with the bcm2835 lib and shown by smufdwag compiles and runs fine on my RPi2 and I can get a varying PWM signal on the 40W connector pin 12 (as seen on my scope and any connected devices). When tra...
by SteveA
Thu Dec 22, 2016 1:16 pm
Forum: Troubleshooting
Topic: Slow i2cdetect on one Pi 3 board only!
Replies: 8
Views: 5159

Re: Slow i2cdetect on one Pi 3 board only!

Of course you don't need to 'muck' about with what the kernel handles in normal times. Perhaps I did not make it clear that it was a method to get going again to be able to reset and continue with pinpointing the cause of the issue - as I said it was easier than repetively rebooting whilst chasing t...
by SteveA
Thu Dec 22, 2016 11:09 am
Forum: Troubleshooting
Topic: Slow i2cdetect on one Pi 3 board only!
Replies: 8
Views: 5159

Re: Slow i2cdetect on one Pi 3 board only!

I had the same problem and it plagued me for many weeks. This is what I found and did to cure it: Sometimes "sudo i2cdetect -y 1" was really slow and it took two or more seconds to test each address. This indicates that the I2C bus has got corrupted, held down or the drivers corrupted. I tried diffe...
by SteveA
Fri Jan 22, 2016 11:02 am
Forum: OpenVG
Topic: OpenVG program crashes randoml, code or faulty unit?
Replies: 17
Views: 7294

Re: OpenVG program crashes randoml, code or faulty unit?

Hello ajstarks,

I have cut sections out bit by bit and have done a test program of my project without my isolated ADC and input/output boards fitted. Could you please pm me to let me know where to email it. Thanks
by SteveA
Tue Jan 19, 2016 1:43 pm
Forum: OpenVG
Topic: OpenVG program crashes randoml, code or faulty unit?
Replies: 17
Views: 7294

Re: OpenVG program crashes randoml, code or faulty unit?

Further to the above I still have a problem where the graphics window gets corrupted after a long time, about 45 mins of continuous looping, which has only come to light this weekend due to the number and frequency of prompts being written to the screen. I am using Raspberry Pi 2, not overclocked, w...
by SteveA
Sun Nov 29, 2015 11:50 am
Forum: OpenVG
Topic: Erasing text leaves shadow/stop graphics swapping to desktop
Replies: 14
Views: 3299

Re: Erasing text leaves shadow/stop graphics swapping to des

Thanks to you all who answered and gave valuable advice and pointeres. The graphics layer now does not flip back to the desktop when the attached USB keyboard is touched after over 10mins of inactivety. I believe it is now fixed and I am sure that the firmware update I did was the cure for this. My ...
by SteveA
Wed Nov 25, 2015 4:18 pm
Forum: OpenVG
Topic: Erasing text leaves shadow/stop graphics swapping to desktop
Replies: 14
Views: 3299

Re: Erasing text leaves shadow/stop graphics swapping to des

Thanks ajstarks for the example of text updating. Is there also an example in 'c' somewhere, as I do not have the Go package.

Is there a link to learn the syntax of Go programming?

Thanks
by SteveA
Wed Nov 25, 2015 4:09 pm
Forum: OpenVG
Topic: Erasing text leaves shadow/stop graphics swapping to desktop
Replies: 14
Views: 3299

Re: Erasing text leaves shadow/stop graphics swapping to des

I have not been around for awhile, hence my delay in responding. Since my last post I have gone through my code from top to bottom and whilst I could find plenty of rubbish I needed to tidy up and streamline, I could not see a definitive issue so I then decided to update the Raspberry Pi and all its...
by SteveA
Mon Sep 21, 2015 9:04 pm
Forum: OpenVG
Topic: Erasing text leaves shadow/stop graphics swapping to desktop
Replies: 14
Views: 3299

Re: Erasing text leaves shadow/stop graphics swapping to des

I am on my way at moment and so will try the suggestions when I get back. Thanks
by SteveA
Mon Sep 21, 2015 6:24 pm
Forum: OpenVG
Topic: Erasing text leaves shadow/stop graphics swapping to desktop
Replies: 14
Views: 3299

Re: Erasing text leaves shadow/stop graphics swapping to des

Thanks Paeryn - the actual program is still running as seen on the connected PC via ssh, because the diagnostic data (adc, loop counts, etc) values are still being read and displayed in the connected ssh PC's terminal and so the program has not finished, even though the graphics layer has gone. It i...
by SteveA
Mon Sep 21, 2015 3:22 pm
Forum: OpenVG
Topic: Erasing text leaves shadow/stop graphics swapping to desktop
Replies: 14
Views: 3299

Re: Erasing text leaves shadow/stop graphics swapping to des

Thanks for explaining the cause of the first problem being due to anti-aliasing. I was hoping to just erase the text rather than erasing a rectangular block, which is what I original did and does work. If you know of a way to overcome this, I would be pleased to hear about it. You are right that it ...
by SteveA
Mon Sep 21, 2015 1:34 pm
Forum: OpenVG
Topic: Erasing text leaves shadow/stop graphics swapping to desktop
Replies: 14
Views: 3299

Erasing text leaves shadow/stop graphics swapping to desktop

I have been using the excellent openvg lib by ajstarks and have come across a few problems, which I hope can be resolved. 1. For example - I create a full screen graphics window in red and set the font to 24 point white (both alpha = 1.0) and draw a text string at a set place on the screen. To erase...
by SteveA
Mon Sep 07, 2015 3:26 pm
Forum: OpenVG
Topic: OpenVG program crashes randoml, code or faulty unit?
Replies: 17
Views: 7294

Re: OpenVG program crashes randoml, code or faulty unit?

Hello ajstarks You've done a really excellent job with your openvg and my program is now looping away merrily, displaying oscilloscope displays, etc. I am really impressed with your routines because I can now display graphical data on the Raspberry Pi with clear text, and not just display scrolling ...
by SteveA
Fri Sep 04, 2015 9:06 am
Forum: OpenVG
Topic: OpenVG program crashes randoml, code or faulty unit?
Replies: 17
Views: 7294

Re: OpenVG program crashes randoml, code or faulty unit?

Thanks again for the heads up. I downloaded the openvg afresh, recompiled and it has run fine for over 8 hours without any corruption (I am continuously looping and displaying 24-bit ADC data onto a panel in a large font size). I am much relieved. I cannot see a change of date from when I last downl...
by SteveA
Thu Sep 03, 2015 12:46 pm
Forum: OpenVG
Topic: OpenVG program crashes randoml, code or faulty unit?
Replies: 17
Views: 7294

Re: OpenVG program crashes randoml, code or faulty unit?

Thanks for letting me know that there could have been an API update. I have just downloaded the whole openvg-master folder again and and have noticed that, for example, the shapes.c file creation date is later than my previous shapes.c file, although on https://github.com/ajstarks/openvg the date co...
by SteveA
Wed Sep 02, 2015 3:35 pm
Forum: OpenVG
Topic: OpenVG program crashes randoml, code or faulty unit?
Replies: 17
Views: 7294

Re: OpenVG program crashes randoml, code or faulty unit?

I have the same or similar problems to those as described here. I use RP2B with the latest OS and firmware updates and the latest openvg-master (as at 2-9-15). After about 90 mins, the screen gets currupted, fonts are drawn incorrectly and in addition, when I quit my application (with the necessary ...
by SteveA
Thu Aug 06, 2015 1:50 pm
Forum: HATs and other add-ons
Topic: Raspberry Pi Isolated Interfaces
Replies: 1
Views: 747

Re: Raspberry Pi Isolated Interfaces

Dean I use them to enable me to regulate 10,000 amp controllers (used in NDT equipment), which, because of the high bus bar currents have terrible earth loop problems, which used to cause massive problems. The isolation provided by the boards mean that the sensors connected to the ADC, the inputs an...

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