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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: 658

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: 598

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: 258
Views: 66923

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: 529

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: 2351

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: 2351

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 ...
by pik33
Sat Aug 17, 2019 6:07 pm
Forum: OpenGLES
Topic: Rpi4 - OpenGL - X - alpha channel - possible?
Replies: 0
Views: 1457

Rpi4 - OpenGL - X - alpha channel - possible?

As in topic.

Is it possible to use alpha channel in OpenGL while displaying in X window? Can a window (with or without OpenGL) be transparent?
by pik33
Fri Aug 16, 2019 6:53 am
Forum: OpenGLES
Topic: Another Pi4 GL working example - Lazarus
Replies: 7
Views: 2351

Re: Another Pi4 GL working example - Lazarus

Strange, I did an apt-get install fpc then apt-get install lazarus and they just worked, weeks? ago. It seems to work until you want to add a component and rebuild Lazarus. Then it crash. It also crashed when I tried to compile the OpenGL example - cannot find openglcontrol or something related to ...
by pik33
Thu Aug 15, 2019 8:07 am
Forum: OpenGLES
Topic: Another Pi4 GL working example - Lazarus
Replies: 7
Views: 2351

Another Pi4 GL working example - Lazarus

Install Lazarus from SVN (not apt-get install :( - the .deb package for Buster is damaged on RPi AND on PC too :( ) svn checkout https://svn.freepascal.org/svn/lazarus/tags/lazarus_2_0_4 cd lazarus_2_0_4 make clean make bigide Run Lazarus Open GL control example Compile Run It simply works As the ex...
by pik33
Mon Aug 12, 2019 6:42 pm
Forum: Bare metal, Assembly language
Topic: Reserving cores for bare-metal programs - interupts
Replies: 36
Views: 3569

Re: Reserving cores for bare-metal programs - interupts

Isn't it possible that the reason of "interrupts" is the memory refresh and/or cpu freq switching thing? I had to add these lines to my baremetal (Ultibo) project's config.txt as I had clicks in my audio (driven by my own driver) #Without these setting there are clicks in the audio. disable_pvt=1 fo...
by pik33
Sun Aug 11, 2019 7:00 am
Forum: OpenGLES
Topic: RPi 4 OpenGL ES 3.0 ShaderToy to download (100+ examples)
Replies: 39
Views: 5154

Re: RPi 4 OpenGL ES 3.0 ShaderToy to download (100+ examples)

You cannot do bare metal in Pi4, but you still can do things without a window manager using Raspbian.
by pik33
Sat Aug 10, 2019 7:41 am
Forum: Polski
Topic: Raspberry Pi 3B a dysk przenośny 4 TB
Replies: 2
Views: 6473

Re: Raspberry Pi 3B a dysk przenośny 4 TB

sudo apt-get install ntfs-3g Powinno żyć. W zależności od maliny, zasilacza i dysku, nawet bez aktywnego huba, ale HDD na ogół będzie jednak go potrzebował. Moje maliny wytrzymują bez problemu dyski przenośne USB3 1 TB. EDIT: Dysk 2TB + szybki pendrive - okazało się że to za dużo dla malinki czwórki...
by pik33
Sat Aug 10, 2019 6:30 am
Forum: Beginners
Topic: Pi 3B+ Overclocking
Replies: 6
Views: 305

Re: Pi 3B+ Overclocking

I have active cooled (3cm fan @3.3v) RPi3 set at 1400/560/560 +force_turbo=1. It can run at 1500 but it is unstable: in (rare) occasion it hangs up, so I left it at 1400. What helps a lot is the core and RAM speed, it gives the RPi3 a lot of additional power even when the CPU is not overclocked
by pik33
Fri Aug 09, 2019 5:53 pm
Forum: OpenGLES
Topic: RPi 4 OpenGL ES 3.0 ShaderToy to download (100+ examples)
Replies: 39
Views: 5154

Re: RPi 4 OpenGL ES 3.0 ShaderToy to download (100+ examples)

These moving sand paintings were all the rage decades ago, got one somewhere.
This still exists and works on RPi4 :)

https://dan-ball.jp/en/javagame/dust/

If this is possible using Java, then shader based sand art should be possible too
by pik33
Fri Aug 09, 2019 4:38 pm
Forum: Advanced users
Topic: 4-bit digital CGA Output from GERT666 (or other GPIO connection)
Replies: 8
Views: 2542

Re: 4-bit digital CGA Output from GERT666 (or other GPIO connection)

Some ideas... Use 4 of 18 bits + sync from VGA666 pins (without connecting a vga666) via a level converter. Set 8-bit framebuffer with such a palette that first 16 colors of it will drive these 4 selected bits as a CGA monitor needs. I don't know if RPi will allow to set a video mode with 7.14 MHz p...
by pik33
Fri Aug 09, 2019 6:34 am
Forum: General discussion
Topic: Overclock RPI4? Where is the limit
Replies: 2
Views: 268

Re: Overclock RPI4? Where is the limit

Experimental:

ARM:

With force_turbo=1: 1830 MHz
With force_turbo=0: 2000 MHz

RPi cannot boot if these frequencies are higher

GPU: 600 MHz

If set higher, it boots, but the real frequency is lower.
by pik33
Thu Aug 08, 2019 6:25 pm
Forum: OpenGLES
Topic: RPi 4 OpenGL ES 3.0 ShaderToy to download (100+ examples)
Replies: 39
Views: 5154

Re: RPi 4 OpenGL ES 3.0 ShaderToy to download (100+ examples)

Landscapes with water, trees and clouds in a few tens of lines of code
This is what you can do using 4096(!) bytes of code - including music:

https://www.youtube.com/watch?v=jB0vBmiTr6o
by pik33
Thu Aug 08, 2019 5:41 pm
Forum: General discussion
Topic: The Raspberry Pi 4 is fast – and hot!!!
Replies: 21
Views: 1626

Re: The Raspberry Pi 4 is fast – and hot!!!

I have some unused old PC cases... maybe it is a fun idea to put a RPi inside :) #4 is fast enough to be confused with a PC; CD ROM can be connected via USB :) Another observations. I have a project using RPi3s. They are mounted vertically to the big device's case and they don't overheat even when o...
by pik33
Mon Aug 05, 2019 8:02 pm
Forum: Graphics programming
Topic: HEVC/H265 Decoding
Replies: 23
Views: 1947

Re: HEVC/H265 Decoding

Now I don't understand this.

I understand the hardware codec is a set of registers at defined addresses. You put commands and parameters there, you get results from there. Why has it to be wrapped in a complex library/api which only 0.001% of people can understand?
by pik33
Mon Aug 05, 2019 11:01 am
Forum: General discussion
Topic: 4gb - 4B Demand must be high.
Replies: 134
Views: 6954

Re: 4gb - 4B Demand must be high.

They have RPi4/4G in Kamami/Poland: they are still available since last days of July. I have one of them on my desk now,, ordered in Friday. 1 terabyte of RAM :) :) :) :) 640 kB ought to be enough for anybody 1980 - 16 kB 1990 - 1 MB 2000 - 64 |MB 2010 - 1 GB 2019 - 16 GB ... let's interpolate :) 20...
by pik33
Sat Aug 03, 2019 1:23 pm
Forum: OpenGLES
Topic: Offline OpenGL render target - is it possible?
Replies: 1
Views: 1111

Offline OpenGL render target - is it possible?

As in the topic title.

Is it possible to allocate a memory for an offline framebuffer and then tell egl? gbm? drm? to render there? May be without X running :)

PS: On RPi4 :) / FKMS
by pik33
Tue Jul 30, 2019 8:16 pm
Forum: OpenMAX
Topic: OpenMax video covers all X window and keeps topmost
Replies: 11
Views: 2689

Re: OpenMax video covers all X window and keeps topmost

The framebuffer is given the lowest layer, which is -127. I experimented with layer <-127 It worked, if the main fb had the alpha channel enabled in config.txt and it was visible via transparent sections in the framebuffer. It was done in Ultibo, but it seems its framebuffer (using standard RPi mai...
by pik33
Sun Jul 28, 2019 4:58 pm
Forum: OpenGLES
Topic: RPi 4 OpenGL ES 3.0 ShaderToy to download (100+ examples)
Replies: 39
Views: 5154

Re: RPi 4 OpenGL ES 3.0 ShaderToy to download (100+ examples)

Downloaded, tested, it works. The only problem I noticed is unresponsible X when playing with "heavy" shaders.
by pik33
Sun Jul 28, 2019 10:55 am
Forum: Advanced users
Topic: RPi4 memory transfer (can it be faster?)
Replies: 2
Views: 241

Re: RPi4 memory transfer (can it be faster?)

Yes it is!!! This version procedure fastmove(from,too,len:integer); label p101 ; begin asm push {r0-r12} ldr r12,len ldr r9,from add r12,r9 ldr r10,too p101: ldr r0,[r9],#4 str r0,[r10],#4 cmps r9,r12 blt p101 pop {r0-r12} end; end; is over 2x faster than ldm unrolled version. 3600 us instead of 780...
by pik33
Sun Jul 28, 2019 9:54 am
Forum: Advanced users
Topic: RPi4 memory transfer (can it be faster?)
Replies: 2
Views: 241

RPi4 memory transfer (can it be faster?)

I tried this procedure to do and test the memory transfer speed in RPi4. (a Pascal procedure, but the body is pure asm) procedure fastmove(from,too,len:integer); label p101 ; begin asm push {r0-r12} ldr r12,len ldr r9,from add r12,r9 ldr r10,too p101: ldm r9!, {r0-r7} stm r10!,{r0-r7} ldm r9!, {r0-r...

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