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by julyjim
Sun Jun 10, 2018 12:16 am
Forum: C/C++
Topic: Raspberry with C++ program
Replies: 17
Views: 7609

Re: Raspberry with C++ program

I'll probably get flamed for saying this, but... to my best knowledge there are no pure C++ "libraries" to START with. However, if you are serious about learning programming in C++ do not start with I/O hardware interfacing. Also using "commands" is not C++ programming. Find IDE of some substance an...
by julyjim
Sat Jun 09, 2018 4:05 pm
Forum: C/C++
Topic: Writing data to BCM2835 - SPI
Replies: 24
Views: 3081

Writing data to BCM2835 - SPI

Up front I am posting this here as a C/C++ request for assistance. Please read and reply to the questions only. I am not interested reading about anything else. If you think I am to obnoxious , I am having bad experience from other forums where people just cannot stay of the subject. This is copy fr...
by julyjim
Fri Jun 08, 2018 1:20 am
Forum: C/C++
Topic: reading pin state
Replies: 5
Views: 746

Re: reading pin state

I think I found my problem - the software
"pins" are zero based and first hardware GPIO is #2.
Classic "fence post error" compounded with juggling three registers same time.
by julyjim
Thu Jun 07, 2018 5:15 pm
Forum: C/C++
Topic: reading pin state
Replies: 5
Views: 746

Re: reading pin state

Thanks for the link. I have been at this for over a month / off and on. Been using one "popular" library" and find it time consuming to try to decipher what the code is doing. I am not against using somebody else code, but at this point I really do not want or need to read thru "how to code in C " d...
by julyjim
Thu Jun 07, 2018 2:24 pm
Forum: C/C++
Topic: reading pin state
Replies: 5
Views: 746

reading pin state

I am writing a "universal" function to control the pin state. What I see in BCM2835 datasheet are three GPIO registers - to set, clear and read the status / level of the pin. These registers , again per BCM2835 datasheet, are not tied to pin mode - input or output. The issue I am having is - when I ...
by julyjim
Mon Jun 04, 2018 4:02 pm
Forum: C/C++
Topic: CSPOL?
Replies: 0
Views: 361

CSPOL?

I am still muddling thru BCM2835 "library", Step by step and making progress. I am in SPI CS "register" and found 4 (four) entries for configuring "chip select" level. In BCM2835 datasheet they go from CSPOL - no number suffix - thru CSPOL0 thru CSPOL2. RPi has two '' chip enable " hardware pins - s...
by julyjim
Wed May 30, 2018 3:19 pm
Forum: C/C++
Topic: Memory mapping offets clarification
Replies: 1
Views: 736

Memory mapping offets clarification

That suppose to be "OFFSETS" - I cannot edit the title Physical addresses range from 0x20000000 to 0x20FFFFFF for peripherals. The bus addresses for peripherals are set up to map onto the peripheral bus address range starting at 0x7E000000. Thus a peripheral advertised in the manual at bus address 0...
by julyjim
Sat May 26, 2018 6:02 pm
Forum: C/C++
Topic: ALT0 and SPI
Replies: 2
Views: 914

Re: ALT0 and SPI

Thanks for reply. That is why I asked - (my) code is pretty "low level" and I am not to the point I can see how writing to MOSI generates / synchronises the clock - but the code essentially does "write" and it better do it to both registers / ports setup for output. I suppose I can set the SPI clock...
by julyjim
Sat May 26, 2018 3:01 pm
Forum: C/C++
Topic: ALT0 and SPI
Replies: 2
Views: 914

ALT0 and SPI

Not sure where to post this. I am still porting bcm2935 code onto C++ class. I have the "GPIO" working, no problem in accessing plain GPIO functions. To use SPI the GPIO "function " has to be changed to "..ATL0". Does such "ALT0" function also changes the direction of the GPIO (register) ? For examp...
by julyjim
Sat May 19, 2018 12:25 am
Forum: C/C++
Topic: ILI9340 "library"
Replies: 2
Views: 497

Re: ILI9340 "library"

Thanks, I was hoping it was something simple as that.
The code complies and runs initializing the GPIO and LCD and has basic "'turn the screen to color" implemented.
Of course it does not work !

It just a matter of making sure all the signals are correct and in right time / place.
by julyjim
Fri May 18, 2018 10:50 pm
Forum: Troubleshooting
Topic: pi zero w test pads for extra USB [solved]
Replies: 21
Views: 12537

Re: pi zero w test pads for extra USB [solved]

Please check USB specification and do not disseminate misleading information. USB devices can share the DATA connection physically / in parallel - they negotiate / share the common data bus as necessary. Of course they can work thru the hub in tree like configuration and then share the common bus el...
by julyjim
Fri May 18, 2018 10:29 pm
Forum: C/C++
Topic: ILI9340 "library"
Replies: 2
Views: 497

ILI9340 "library"

I am not sure where to post this , but here it comes. I am trying to learn about C++ inheritance so I took a set of C libraries and I am rewriting them for C++. Run into small issue with assigning I/O pins. Different versions of Raspberry Pi have different I/O pinout, however after much search in ex...
by julyjim
Mon May 14, 2018 1:27 pm
Forum: C/C++
Topic: bcm2835 port function etc etc
Replies: 13
Views: 1255

Re: bcm2835 port function etc etc

Would somebody care to explain how did this text ended up on my terminal? I did copy it here , but how it got to the terminal? This is a technical question, no moral issue whatsoever. Let's see, you copied a piece of text earlier and then it appears in your terminal... pretty obvious that you paste...
by julyjim
Sun May 13, 2018 8:32 pm
Forum: C/C++
Topic: bcm2835 port function etc etc
Replies: 13
Views: 1255

Re: bcm2835 port function etc etc

Would somebody care to explain how did this text ended up on my terminal? I did copy it here , but how it got to the terminal? This is a technical question, no moral issue whatsoever. os64@os64-desktop:~$ My choice, now, is to pretty much ignore your posts, and I suspect others will do the same. Fin...
by julyjim
Sun May 13, 2018 8:16 pm
Forum: C/C++
Topic: bcm2835 port function etc etc
Replies: 13
Views: 1255

Re: bcm2835 port function etc etc

My choice, now, is to pretty much ignore your posts, and I suspect others will do the same. Finding the documentation on this website is simple, which is why I didn't post a link, and yet you didn't even bother to try to find it. The time you spent typing in your unnecessarily rude reply would easil...
by julyjim
Sun May 13, 2018 12:04 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Need true SPI device with datasheet
Replies: 1
Views: 224

Need true SPI device with datasheet

I am testing my SPI coding skills and I am unable to get MISO signals from device I am using. I like to have an inexpensive "breakout module" with true , only 4 wires , SPI interface and real datasheet. I don't want a device with "C/D" or similar pin. The datasheet has to have detailed "commands" an...
by julyjim
Sat May 12, 2018 11:47 pm
Forum: C/C++
Topic: bcm2835 port function etc etc
Replies: 13
Views: 1255

Re: bcm2835 port function etc etc

You forgot to say "google it!".
Vague reference to "somewhere here " is not an answer I would expect from professional.
Humour me and point me to ONE resource on this site.
Your choice.
by julyjim
Sat May 12, 2018 6:30 pm
Forum: C/C++
Topic: TCF Target communication framwork - anybody?
Replies: 0
Views: 251

TCF Target communication framwork - anybody?

After purchasing RPi for PURPOSE to develop C/C++ applications and as a replacement for "toy processor " I have been struggling with , I realized that I'll be better of developing on PC (as host) and using RPi as "remote". Than I discovered TCF. So here I was - new "embedded hardware' , new OS - sta...
by julyjim
Sat May 12, 2018 6:17 pm
Forum: C/C++
Topic: bcm2835 port function etc etc
Replies: 13
Views: 1255

bcm2835 port function etc etc

Hello, there are oodles of "trivial information " on web about Raspberry Pi - " fastest gun in the west ", "smallest processor around" etc etc. How about something real ? How do you use "RECOVERY " especially when my new clean OS download DOES NOT have "RECOVERY " partition on the SD? RPi 3B alleged...
by julyjim
Wed May 09, 2018 8:46 pm
Forum: General discussion
Topic: Etcher does not recognize OS .zip files downloads ?
Replies: 21
Views: 3925

Re: Etcher does not recognize OS .zip files downloads ?

No, I did not follow the install instruction - I cannot get the .zip to extract to SD. I do not have some mysterious permission to move .zip file to SD device. When I try to just extract from Download it also fails - but gives just "error" when I select the SD /dev. to "extract to ". Until I do - th...
by julyjim
Wed May 09, 2018 5:38 pm
Forum: General discussion
Topic: Etcher does not recognize OS .zip files downloads ?
Replies: 21
Views: 3925

Re: Etcher does not recognize OS .zip files downloads ?

OK, responsibility aside - why I cannot move RPi .zip file to /dev/x? What is so specific about RPi .zip? Both NOOBS and Raspian behave same. BTW -it takes forever to download "genuine" RPi software from this site. It sure looks as Windoze file hence unusable by Linux. Changing user does not help. R...
by julyjim
Tue May 08, 2018 1:26 pm
Forum: General discussion
Topic: Etcher does not recognize OS .zip files downloads ?
Replies: 21
Views: 3925

Re: Etcher does not recognize OS .zip files downloads ?

Yes and no I did try both .zip and Torrent Then I got the foolish idea to "just move " download to Etcher and got something about "cannot do backed " So far no success getting clean OS to SD. Funny part - I found another SD and it boots and stops at " starting NTP server" . I am going to post my "tr...
by julyjim
Mon May 07, 2018 5:27 pm
Forum: General discussion
Topic: OK, I lost my post THREE times
Replies: 4
Views: 425

Re: OK, I lost my post THREE times

Thanks for replies. I had some issues downloading OS and found an archive copy of my initial SD. I did manage to use Linux "dd" to duplicate it to my spare SD. Pretty nice but SLOOOW process. Unfortunately the archive SD did not finish loading the OS to RPi either. Therefore I am convinced that my R...
by julyjim
Mon May 07, 2018 5:15 pm
Forum: General discussion
Topic: Etcher does not recognize OS .zip files downloads ?
Replies: 21
Views: 3925

Re: Etcher does not recognize OS .zip files downloads ?

So, I would say this is pretty normal problem created by...
Found a different, albeit very slow way to duplicate my archive SD in Linux.
Problem solved , case closed.
by julyjim
Sun May 06, 2018 10:45 pm
Forum: General discussion
Topic: OK, I lost my post THREE times
Replies: 4
Views: 425

OK, I lost my post THREE times

What is RPi real boot sequence ?
I have a "boot" folder and it is probably in wrong place.

Save draft and load draft produced only part of my text.
I need to post this and then I'll figure out why it did not work.
Obviously - it is user error ...

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