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by Gert van Loo
Wed Dec 06, 2017 11:15 pm
Forum: Troubleshooting
Topic: 2N2222 driven LED strip
Replies: 11
Views: 1405

Re: 2N2222 driven LED strip

Hi, If you are planning to work on 2n2222, then you must have a look at Introduction to 2n2222 . I have shared detailed overview of how it works and have also shared its working Proteus Simulation. Thanks. I have looked at your page and I appreciate the effort yo put int it BUT! The way you use the...
by Gert van Loo
Sat Dec 02, 2017 3:40 pm
Forum: B+ addons
Topic: Gert's VGA - 888 possible?
Replies: 7
Views: 1545

Re: Gert's VGA - 888 possible?

In all the posts below nobody seems to have mentioned an Interesting fact: Not all the resistors have to 0.4%.
The big ones have to be accurate as their deviation should be smaller then the value of the smallest resistor.
by Gert van Loo
Thu Nov 30, 2017 9:51 pm
Forum: Gertboard classic
Topic: Gertbot Control using Python Drivers
Replies: 8
Views: 4224

Re: Gertbot Control using Python Drivers

I am looking into this.
What version raspberry-Pi are you using?
I assume a Pi-3? If so check if your UART settings are correct.
See here: https://www.gertbot.com/pi3.html
You might also have to add "core_freq=250" to the /boot/config.txt file.
by Gert van Loo
Mon Nov 27, 2017 5:34 pm
Forum: Add-ons
Topic: Anybody interested in talking direct! to IDE/SATA?
Replies: 23
Views: 1000

Re: Anybody interested in talking direct! to IDE/SATA?

I never know exactly what to do with git so this is what I did:
- Forked the documentation.
- Uploaded the file to hardware/raspberrypi/bcm2835.
- Created a pull request.

If any of that needs changing let me know.
by Gert van Loo
Mon Nov 27, 2017 3:24 pm
Forum: Add-ons
Topic: Anybody interested in talking direct! to IDE/SATA?
Replies: 23
Views: 1000

Re: Anybody interested in talking direct! to IDE/SATA?

Issues!!!! Tried to attached it to this post but the website does not accept .pdf file. I uploaded it to scribd to have it exists alongside my other Pi documents. Set it to public (lock is open) but it does NOT appear on the main page. I have raised a question with Scribd. Before you all start comme...
by Gert van Loo
Mon Nov 27, 2017 9:36 am
Forum: Add-ons
Topic: Anybody interested in talking direct! to IDE/SATA?
Replies: 23
Views: 1000

Re: Anybody interested in talking direct! to IDE/SATA?

Any patented stuff? No, as I said there is nothing special about the SMI. For those interested a bit of history: The first Raspberry-Pi 2835 was originally a 2708. The 2708 was the same die in a different package which had two 128Mbyte stacked SDRAM chips inside. However there also was a 2707, the ...
by Gert van Loo
Sun Nov 26, 2017 3:21 pm
Forum: Add-ons
Topic: Anybody interested in talking direct! to IDE/SATA?
Replies: 23
Views: 1000

Re: Anybody interested in talking direct! to IDE/SATA?

If I remember, I'll try and find out why we have never released that information. It might simply be lack of time. I have just created a stand-alone version of the SMI specs. I COULD publish it right now but I am not sure what the legal side of this is. On the one side, I was the one who decided wh...
by Gert van Loo
Wed Nov 22, 2017 5:45 am
Forum: Add-ons
Topic: Anybody interested in talking direct! to IDE/SATA?
Replies: 23
Views: 1000

Re: Anybody interested in talking direct! to IDE/SATA?

We did some I/O test on the pi many, many years ago. (My god, I am getting old...) At 100 MHz the signal looked more like a sine wave. So my guess is that 50-75 MHz is about the limit. At 16 bits wide that is 100-150 Mbyte/sec. I am looking forward to see how far you get with this. Uhhh.... I have g...
by Gert van Loo
Tue Nov 21, 2017 6:46 pm
Forum: Add-ons
Topic: Anybody interested in talking direct! to IDE/SATA?
Replies: 23
Views: 1000

Re: Anybody interested in talking direct! to IDE/SATA?

Looks like you are using CPLD in the schematics so the IDE interface cannot be driven directly by SMI? The CPLD was 'just in case'. The current code works without it. (Although maybe it is needed after all to get the DMA sorted out) That is also in the read me file in the schematics. 16 bit wide me...
by Gert van Loo
Tue Nov 21, 2017 10:47 am
Forum: Add-ons
Topic: Anybody interested in talking direct! to IDE/SATA?
Replies: 23
Views: 1000

Re: Anybody interested in talking direct! to IDE/SATA?

I will put it alongside the VGA on Github. (I never was good at working with Git so it might be a bit messy) There is also a complete (free!) database for a 128 port I/O card there on Github but nobody seem to have discovered that yet! Can this SMI be also used to connect two Pis and have bidirectio...
by Gert van Loo
Thu Nov 16, 2017 8:03 pm
Forum: Add-ons
Topic: Anybody interested in talking direct! to IDE/SATA?
Replies: 23
Views: 1000

Anybody interested in talking direct! to IDE/SATA?

I recently found the remains of a project I started three years ago on my hard drive. The idea was to use the Raspberr-Pi SMI (which stands for Secondary Memory Interface) to talk to an IDE interface. Although IDE is old there are still IDE to SATA adapters so it might be used to talk to SATA as wel...
by Gert van Loo
Wed Nov 08, 2017 7:18 pm
Forum: Nederlands
Topic: Ik wil graag een programma starten bij opstarten ( crontab)
Replies: 18
Views: 1749

Re: Ik wil graag een programma starten bij opstarten ( crontab)

Humm, als je ergens in het noorden van het land zit wil ik best langs komen om even te kijken....
(Maar waarschijnlijk niet, tenslotte schiet de politie hier nog met pijl en boog, althans volgens de meeste westerlingen :lol: )
by Gert van Loo
Mon Nov 06, 2017 1:04 pm
Forum: Nederlands
Topic: ssh says at password all the time: "permission denied, please try later"
Replies: 14
Views: 692

Re: ssh says at password all the time: "permission denied, please try later"

OK pretty stupid and basic but I have to ask: have you enabled ssh in the raspi-setup?
by Gert van Loo
Thu Nov 02, 2017 11:50 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: GPIO max current
Replies: 34
Views: 62589

Re: GPIO max current

Is the 50mA a hard number? NO! It is good design practice. It depends on too may factors like: - Quality of power supply - Type of pin load (capacitive, resistive or inductive and amount of capacity/inductance) - Quality of board routine - Quality and amount plus placement of chip decoupling - How m...
by Gert van Loo
Thu Nov 02, 2017 11:26 pm
Forum: Nederlands
Topic: "Gestures" op RPI aangesloten touchscreen voorkomen
Replies: 2
Views: 289

Re: "Gestures" op RPI aangesloten touchscreen voorkomen

Ik ben geen expert op het gebied van Chromium maar aangezien de vraag al vijf dagen openstaat: Nee. Als je een standaard programma opstart ben je afhankelijk van wat dat programma doet. Sommige programmas kun je aan passen maar ik heb nog nooit gezien dat je fundamentele dingen als zoom, context, cl...
by Gert van Loo
Thu Nov 02, 2017 12:16 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: GPIO max current
Replies: 34
Views: 62589

Re: GPIO max current

Me.
by Gert van Loo
Mon Oct 23, 2017 9:11 pm
Forum: Nederlands
Topic: Ik wil graag een programma starten bij opstarten ( crontab)
Replies: 18
Views: 1749

Re: Ik wil graag een programma starten bij opstarten ( crontab)

Mag ik concluderen dat dit programma op de achtergrond draait en dat ik het in rc.local met een ampersant erachter kan opnemen???? Uhh... ik weet het niet zeker. Als het programma een grafische interface heeft vermoed ik dat die ook zal verschijnen waneer het me cron gestart wordt. Maar ik weet nie...
by Gert van Loo
Mon Oct 23, 2017 7:38 pm
Forum: Nederlands
Topic: Ik wil graag een programma starten bij opstarten ( crontab)
Replies: 18
Views: 1749

Re: Ik wil graag een programma starten bij opstarten ( crontab)

.... Als ik dit commando in een commandscreen geef, werkt het normaliter ook en kan ik het uitzetten met ctrl C maar dit werkt nu ook niet meer. Als je een programm met control-C moet eindigen kun je het niet in rc.local zetten. Maar er is een anomaly: Ik zie dat het commando eindigd met de ampersa...
by Gert van Loo
Sun Oct 15, 2017 11:52 am
Forum: Nederlands
Topic: Ik wil graag een programma starten bij opstarten ( crontab)
Replies: 18
Views: 1749

Re: Ik wil graag een programma starten bij opstarten ( crontab)

moet het niet gewoon in init.d gezet worden? Pit Hangt er vanaf wat voor programma gestart wordt en of het ook gestopt moet worden. init.d is bedoelt voor services. rc.local is het eenvoudigst want het heeft de minste regels/condities/voorwaarden. Dit: https://unix.stackexchange.com/questions/18804...
by Gert van Loo
Tue Oct 10, 2017 8:33 pm
Forum: Troubleshooting
Topic: Re-start with three cores corrupts SD-card?
Replies: 11
Views: 709

Re: Re-start with three cores corrupts SD-card?

I was wondering because the times it was going OK I was using a jessie-light image. Just switched back to full blown jessie, edit cmdline.txt: 1/ Removed console 2/ Added maxcpus=3 Save Sudo halt wait until led is off. Remove power, apply power: reboot and image is corrupt!!! Would appreciate if som...
by Gert van Loo
Tue Oct 10, 2017 8:21 pm
Forum: Troubleshooting
Topic: Re-start with three cores corrupts SD-card?
Replies: 11
Views: 709

Re: Re-start with three cores corrupts SD-card?

Did you wait for the 10 flashes to finish before pulling the power?
Good question but yes, I always do.
(I am not that new to the Pi you know, I have been using them for rather a long time. :-) :-) )
by Gert van Loo
Tue Oct 10, 2017 4:18 pm
Forum: Troubleshooting
Topic: Re-start with three cores corrupts SD-card?
Replies: 11
Views: 709

Re: Re-start with three cores corrupts SD-card?

I only tried with 3 CPUs.

I just tried twice more to start and it was OK.
I thought it was unlikely to be a bug as somebody would have noticed by now
but three times in a row made me suspicious.
by Gert van Loo
Tue Oct 10, 2017 11:38 am
Forum: Troubleshooting
Topic: Re-start with three cores corrupts SD-card?
Replies: 11
Views: 709

Re: Re-start with three cores damages SD-card?

I can restore the SD card by re-flashing.

(Changed the title to reflect this)
by Gert van Loo
Tue Oct 10, 2017 9:22 am
Forum: Troubleshooting
Topic: Re-start with three cores corrupts SD-card?
Replies: 11
Views: 709

Re-start with three cores corrupts SD-card?

I changed the command line to use three cores: maxcpus=3. I found that reboot gave no problems but after a full shutdown+power off at the next full re-start the SD-card appears damaged. This has now happened three times once with a different Pi-3. I can't help but suspect very much that there is a a...
by Gert van Loo
Sat Oct 07, 2017 1:46 pm
Forum: Gertboard classic
Topic: Gertboard with Pi2 Jessie
Replies: 3
Views: 946

Re: Gertboard with Pi2 Jessie

The change in port mapping on the Pi2/3
That remark reminded me: On the Pi2 and Pi3 the peripheral base address has been moved!!

On Pi1 it is 0x20000000 on Pi2 and 3 it is 0x3F000000.

gb_common.c:
#define BCM2708_PERI_BASE ...

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