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by franekz
Mon Oct 30, 2017 10:56 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: GPIO max current
Replies: 34
Views: 94437

Re: GPIO max current

boyoh wrote:
Mon Oct 30, 2017 10:50 pm
but no more than 50ma from the Pi at a voltage of 3.3v+,
Which is not the truth on the new PIs
by franekz
Mon Oct 30, 2017 10:18 pm
Forum: Advanced users
Topic: Hat EEPROM image GPIO settings.
Replies: 0
Views: 197

Hat EEPROM image GPIO settings.

Hi guys. I have gone through the documentation and design guides of the hats but cant understand the pin usage. I have a hat. It potentially can be connected using both SPIs and 5 diferent CS lines. It is configured by the used using the jumpers. The interface has to be enabled by the user. The hat ...
by franekz
Sun Apr 16, 2017 6:54 pm
Forum: HATs and other add-ons
Topic: B+HAT EEPROM
Replies: 7
Views: 3995

Re: B+HAT EEPROM

Logically yes but I have just got another answer from RPi staff stating NO EEPROM - NO HAT!

RPi firmware changes do not affect the way EEPROM (or emulated EEPROM) works.
by franekz
Sun Apr 16, 2017 6:30 pm
Forum: HATs and other add-ons
Topic: B+HAT EEPROM
Replies: 7
Views: 3995

Re: B+HAT EEPROM

It is a general question. Not about any particular one.
by franekz
Sun Apr 16, 2017 5:18 pm
Forum: HATs and other add-ons
Topic: B+HAT EEPROM
Replies: 7
Views: 3995

B+HAT EEPROM

Hi. I have a quite simple question. Does the hat have to have EEPROM IC or it is enough to emulate EEPROM by by the HATs uC? It has exactly the same functionality.
by franekz
Tue Mar 28, 2017 8:51 am
Forum: C/C++
Topic: Assembly function array output
Replies: 14
Views: 1431

Re: Assembly function array output

[quote="KnarfB"] [code]#include <stdio.h> #include <stdint.h> uint32_t a[] = {0x5139, 0x8a58, 0x9b81, 0xf544}; uint32_t b[] = {0x0e96, 0x9def, 0x0b15, 0x863d}; uint32_t r[] = {0}; void myadd(uint32_t *restrict a, uint32_t *restrict b, uint32_t *restrict r) { for( int i=0; i<4; ++i ) r[i] = a[i] + b[...
by franekz
Mon Mar 27, 2017 5:47 pm
Forum: C/C++
Topic: Assembly function array output
Replies: 14
Views: 1431

Re: Assembly function array output

Because eventually you want to do it faster with SIMD (which compilers are not so good at). I agree, for something like this, the compiler will do a much better job, especially a recent version of the compiler (GCC 6 or later). But you will learn a lot more about ARM with a few lines of assembler t...
by franekz
Mon Mar 27, 2017 4:36 pm
Forum: C/C++
Topic: Assembly function array output
Replies: 14
Views: 1431

Re: Assembly function array output

BTW - what is the reason to write such a code in the assembler. Do you think that you are better than the compiler? Assembler makes sense only if you write processor specific routines.
by franekz
Sun Mar 26, 2017 5:23 pm
Forum: C/C++
Topic: AUXSPI0/1_STAT Register
Replies: 3
Views: 423

Re: AUXSPI0/1_STAT Register

#define AUXSPI_STAT_TX_FIFO(x) ((x)<<28) #define AUXSPI_STAT_RX_FIFO(x) ((x)<<20) #define AUXSPI_STAT_TX_FULL (1<<10) #define AUXSPI_STAT_TX_EMPTY (1<<9) #define AUXSPI_STAT_RX_EMPTY (1<<7) #define AUXSPI_STAT_BUSY (1<<6) #define AUXSPI_STAT_BITS(x) ((x)<<0) Are you sure TX_EMPTY is it 1 << 9 or 1 ...
by franekz
Sun Mar 26, 2017 4:19 pm
Forum: C/C++
Topic: AUXSPI0/1_STAT Register
Replies: 3
Views: 423

AUXSPI0/1_STAT Register

Hi. Does anyone know the real structure of the AUXSPI0/1_STAT Register register? The one from documentation is much to long (36 bits instead of 32).Image
by franekz
Sat Mar 25, 2017 5:42 pm
Forum: C/C++
Topic: SPI1 Registers in user space. How to enable clock ?
Replies: 4
Views: 745

Re: SPI1 Registers in user space. How to enable clock ?

Thank you very much again :)

I know my mistake. I took the address of microSPI as SPI0. My fault. Thank you very much indeed
by franekz
Sat Mar 25, 2017 12:04 pm
Forum: C/C++
Topic: SPI1 Registers in user space. How to enable clock ?
Replies: 4
Views: 745

Re: SPI1 Registers in user space. How to enable clock ?

Thank you very much :)
But can you give me a general idea where did you get this number from. I try to understand it but I cant find any offset of 0x20400 bytes in that documentation.
by franekz
Sat Mar 25, 2017 11:19 am
Forum: C/C++
Topic: SPI1 Registers in user space. How to enable clock ?
Replies: 4
Views: 745

SPI1 Registers in user space. How to enable clock ?

Hi. I never used to program hardware registers in user space in Linux - on this field I am an absolute beginner. I struggle to understand how addresses are calculated. As a reference I took the bcm2385.c library and https://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf A...
by franekz
Fri Mar 24, 2017 12:18 pm
Forum: Python
Topic: SPI1 polarity and active egge.
Replies: 2
Views: 404

Re: SPI1 polarity and active egge.

Actually BCM 19,20,21 or pins 35,38,40.

BCM datasheet - both can have clock inverted theoretically
by franekz
Fri Mar 24, 2017 11:30 am
Forum: Python
Topic: SPI1 polarity and active egge.
Replies: 2
Views: 404

SPI1 polarity and active egge.

Hi, Have a problem with SPI1 interface on Jessie (the latest version form the site - installed 3 days ago). I use spidev and everything works great except polarity & active edge on SPI1. SPI0 works fine. Checked with logic analyser - here is no reaction on those bits. It is a quite serious issue for...
by franekz
Fri Feb 17, 2017 12:27 pm
Forum: General discussion
Topic: Does anyone know any ADC / DAC all in one hats
Replies: 6
Views: 1769

Re: Does anyone know any ADC / DAC all in one hats

I have eventually found one on kickstarter
by franekz
Fri Feb 17, 2017 9:28 am
Forum: General discussion
Topic: Script execution when turning on the RPi
Replies: 4
Views: 751

Re: Script execution when turning on the RPi

Just show in brief what you want to archieve. There are may options how to tun scripts on boot, depending what privileges script needs to have and another circumstances. To help you I need to know more.
by franekz
Thu Feb 16, 2017 8:41 pm
Forum: General discussion
Topic: Does anyone know any ADC / DAC all in one hats
Replies: 6
Views: 1769

Does anyone know any ADC / DAC all in one hats

Hi Guys. For my project I need to read and write analog ports. On the market I have found many ADC hats (unfortunately most of them are a very slow I2C ones), and some DACs (and again usually only one port - I do not need it for audio). Another problem is that I prefer to have only one hat, not the ...

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