Go to advanced search

by pik33
Fri Jun 05, 2020 11:07 am
Forum: Troubleshooting
Topic: Audacity doesn't see any audio devices in new RPi OS
Replies: 6
Views: 303

Audacity doesn't see any audio devices in new RPi OS

Both 32- and 64-bit OS.

The symptom is: Audacity can see only dmix device and dosen't output any audio via headphone jack, while any other program I tested so far plays audio without problems.
by pik33
Wed May 27, 2020 9:42 am
Forum: Graphics programming
Topic: Garbled screen with latest 5.4 firmware and fkms
Replies: 3
Views: 386

Re: Garbled screen with latest 5.4 firmware and fkms

I returned to the old firmware.

It looked like a set of horizontal strips of rainbow colored pixels, several pixels wide, with black gaps between them.

As if something was wrong with the pitch.
by pik33
Wed May 27, 2020 6:44 am
Forum: Graphics programming
Topic: Garbled screen with latest 5.4 firmware and fkms
Replies: 3
Views: 386

Re: Garbled screen with latest 5.4 firmware and fkms

Yesterday I tried to rpi-update to the latest firmware. Then the Atari ST emulator, Hatari, displayed garbage instead of full screen graphics. After some playing with it I discovered that the fullscreen is OK if I switch the "vsync" option in Hatari off. I returned to the stable firmware version whi...
by pik33
Mon May 25, 2020 4:24 pm
Forum: Troubleshooting
Topic: CPU Freq applet shows incorrect frequency when OC RPi4
Replies: 0
Views: 56

CPU Freq applet shows incorrect frequency when OC RPi4

I tried to extremally overclocking RPi4. I set it to 2100 MHz with 750 MHz GPU

Then the frequency applet (in the taskbar) shows 2294 MHz while vcgencmd shows correctly 2100 MHz

My own program which reads from '/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq' also shows 2294 MHz.
by pik33
Wed Apr 08, 2020 6:54 am
Forum: Bare metal, Assembly language
Topic: A bootloader over serial for bare metal rpi development
Replies: 5
Views: 571

Re: A bootloader over serial for bare metal rpi development

Is there a version of such a loader which if theere is no communication on the serial port (timeout), loads a predefined kernel file from the SD card?
by pik33
Thu Feb 27, 2020 8:22 pm
Forum: Bare metal, Assembly language
Topic: RPi4 4GB: Kernel Space Memory Addressing
Replies: 4
Views: 705

Re: RPi4 4GB: Kernel Space Memory Addressing

RPI4 GPU RAM (for the legacy stuff left in the firmawre) still has to be allocated in the first GB and this causes the memory split. And it is still allocated from the 1st GB boundary down.
by pik33
Fri Jan 24, 2020 1:27 pm
Forum: Bare metal, Assembly language
Topic: Understanding BCM2835 memory map
Replies: 2
Views: 1041

Re: Understanding BCM2835 memory map

7E address range is the hardware address. For example if you program the DMA chip to send data to the hardware register (for example PWM) you have to use 7E based address as a destination address in the DMA description block 20/3F address range is what ARM processor can see so if you want to put dat...
by pik33
Wed Jan 22, 2020 12:21 pm
Forum: Bare metal, Assembly language
Topic: Support for audio in the USB driver?
Replies: 1
Views: 600

Re: Support for audio in the USB driver?

SimpleAudio is the audio driver for the audio jack only. It doesn't support any other audio devices (USB, I2S, HDMI).
by pik33
Fri Dec 20, 2019 8:51 am
Forum: OpenGLES
Topic: Understanding glxgears performance on Pi4
Replies: 7
Views: 1082

Re: Understanding glxgears performance on Pi4

The keyword is: RAM bandwidth. Theoretical maximum RAM bandwidth in RPi4 should be 12.8 GBps. In reality you have to send commands to the RAM, etc, and the real bandwidth will be much less. For the ARM on RPi4 maximum it can do is something more than 4 GBps but less than 5 GBps (this is what I measu...
by pik33
Tue Nov 19, 2019 7:35 am
Forum: Bare metal, Assembly language
Topic: Circle - C++ bare metal environment (with USB)
Replies: 273
Views: 84732

Re: Circle - C++ bare metal environment (with USB)

Hello, As i mentioned in an other post i am porting the PreenFM2-Synth to baremetal RaspberryPi with the Circle-Framework, and so far it seems to work! its really ugly but if anybody wants to try it out: https://github.com/styro2000/RasPreenFM2/ Now am am trying to optimize things to get an better ...
by pik33
Sun Oct 13, 2019 9:54 am
Forum: OpenGLES
Topic: Web shader toys don't work - too advanced for RPi4?
Replies: 3
Views: 2832

Re: Web shader toys don't work - too advanced for RPi4?

A strange thing.

The shader I linked in the first post works on RPi3 and doesn't work (displaying a black screen) on RPi4
by pik33
Sat Oct 12, 2019 8:41 am
Forum: General programming discussion
Topic: Programming languages support
Replies: 37
Views: 5613

Re: Programming languages support

and the ONLY other camera library I know about is in Python.
I made this for Ultibo: https://github.com/pik33/SimpleCamera
by pik33
Sat Oct 12, 2019 7:00 am
Forum: Bare metal, Assembly language
Topic: Bare metal à la Arduino...
Replies: 7
Views: 2104

Re: Bare metal à la Arduino...

You may have a look at Circle. Wow, you have RPi4 supported - to be tested :) although c++ is not my favourite language. I saw RPi4 audio there at PWM#1... so I have questions (I didn't manage to find it in the code - where to search this?): - the clock source address for PWM1 - is it the same or a...
by pik33
Wed Oct 09, 2019 9:11 am
Forum: Bare metal, Assembly language
Topic: Bare metal à la Arduino...
Replies: 7
Views: 2104

Re: Bare metal à la Arduino...

Yes, the Ultibo is a customized Lazarus. You can do sudo apt-get lazarus, but I had some problems with this version on Raspbian (and PC debian too) so I built my own Lazarus for Raspbian from sources. In Windows, simply get a Lazarus from here https://www.lazarus-ide.org and install it Lazarus is a ...
by pik33
Wed Oct 09, 2019 7:34 am
Forum: Bare metal, Assembly language
Topic: Bare metal à la Arduino...
Replies: 7
Views: 2104

Re: Bare metal à la Arduino...

Yes, we have. With libraries for almost everything (no wifi yet, but vc4/omx/opengl is there) Works with RPi 0/1/2/3 (no RPi4 yet because of the new hardware - work in progress) The environment is called Ultibo "Normal" mode of operation is: install Ultibo on Windows, create a project, compile, copy...
by pik33
Sat Oct 05, 2019 4:00 pm
Forum: Graphics programming
Topic: Questions about fkms, gbm and color alpha channel
Replies: 6
Views: 2186

Re: Questions about fkms, gbm and color alpha channel

I also didn't manage to get any transparency/alpha channel using RPi4/FKMS. What I tried to achieve was an OpenGL window with a transparent background, so only 3D objects are visible. Using Lazarus, as it is multiplatform environment, and its OpenGL context component to start OpenGL, setting alpha b...
by pik33
Fri Oct 04, 2019 4:19 am
Forum: Bare metal, Assembly language
Topic: Spider-OS a new operating system
Replies: 113
Views: 24062

Re: Spider-OS a new operating system

a new follower of the assembler Not new :) Using asm for over 30 years :) But on RPi i use asm mixed with high level languages to speed up/make things possible. I wrote (1) SID emulator (https://github.com/pik33/ultibo_retro_gui/blob/master/retromalina.pas line 2423) (2) noise shaper for audio driv...
by pik33
Thu Oct 03, 2019 4:03 pm
Forum: Bare metal, Assembly language
Topic: Spider-OS a new operating system
Replies: 113
Views: 24062

Re: Spider-OS a new operating system

I added your website to my bookmarks.

Is there this fasmarm assembler available on RPi? I don't want to use a PC for RPi programming :)
by pik33
Thu Sep 05, 2019 3:22 pm
Forum: Bare metal, Assembly language
Topic: Clean, OS-independent Pi programming using C/C++
Replies: 11
Views: 1974

Re: Clean, OS-independent Pi programming using C/C++

Yes, it is, but it is Pascal. The Ultibo environment is an open source environment for programming RPi without OS and you can find a lot of hardware related information on its forum and its source files. As it is now Ultibo became a complex environment with a lot of operating system functionality, b...
by pik33
Wed Sep 04, 2019 4:41 am
Forum: Bare metal, Assembly language
Topic: Raspbian assembly draw a line on screen
Replies: 7
Views: 1675

Re: Raspbian assembly draw a line on screen

I have some graphics primitives here: https://github.com/pik33/ultibo_retro_gui/blob/master/retromalina.pas I did a "box" (filled rectangle) in asm; the rest of them are Pascal, using "putpixel" to put a pixel. I planned to rewrite them in asm but they are simply enough fast for me as they are now. ...
by pik33
Wed Aug 28, 2019 7:31 am
Forum: Gentoo
Topic: Updated 64-bit Gentoo Image for RPi3 Released (now also for RPi3B+ and RPi4B)
Replies: 505
Views: 135187

Re: Updated 64-bit Gentoo Image for RPi3 Released (now also for RPi3B+ and RPi4B)

First try with RPi4B/4GB: no wifi. The symptom is: it detects the router and asks for the password again and again. There is no problem with this router in Raspbian: you write a password and it connects. To be investigated later.
by pik33
Fri Aug 23, 2019 4:54 am
Forum: Bare metal, Assembly language
Topic: some basic raspberry pi questions related to chadderz121 tutorials
Replies: 5
Views: 1642

Re: some basic raspberry pi questions related to chadderz121 tutorials

The framebufer: You tell the GPU subsystem via its mailbox interface to make a framebuffer for you and return a pointer to it. All pixel, lines and characters drawing there is up to you. You put bytes there, GPU displays pixels from there. There is no automatic machine/2D accelerator which makes GPU...
by pik33
Sun Aug 18, 2019 6:11 am
Forum: OpenGLES
Topic: Another Pi4 GL working example - Lazarus
Replies: 7
Views: 4913

Re: Another Pi4 GL working example - Lazarus

This bgra stuff, without a typo, costed me a lot of time to debug, as the texture was black. So I played with the shader to switch this on, off, etc until I tried to switch to rgba and voila: what should be red was blue, but at least not black. So I tried to return to bgra with the second argument: ...
by pik33
Sat Aug 17, 2019 6:55 pm
Forum: OpenGLES
Topic: Another Pi4 GL working example - Lazarus
Replies: 7
Views: 4913

Re: Another Pi4 GL working example - Lazarus

I have now my cube-and-sphere demo working using Lazarus in Raspbian/X (without a text display yet) Differences between RPi3/Ultibo/OpenGL ES 2 and RPi4/X/OpenGL 2.,1 encountered so far: - no precision in shaders, they cannot compile with it - bgra textures seem to be not supported. The texture has ...

Go to advanced search