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by HiassofT
Sat May 02, 2020 7:18 pm
Forum: General discussion
Topic: How to monitor two infrared sensors individually
Replies: 4
Views: 186

Re: How to monitor two infrared sensors individually

You can load the gpio-ir overlay multiple times (with different gpio_pin parameters), this will give you two rc, lirc and input event devices. Just use ir-keytable to configure those (either to identical or different protocols / keymaps) and read the events from the lirc or input devices (adding a u...
by HiassofT
Sun Apr 26, 2020 9:32 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: What's the reason for 24/192 khz limitation for pcm output?
Replies: 1
Views: 211

Re: What's the reason for 24/192 khz limitation for pcm output?

The limit is actually 384kHz/32bit at 2 channels, Eric Anholt confirmed that the docs state a maximum bclk of 25MHz. There are no clock sources inside the RPi that are suitable to derive audio clock rates with an integer divisor (except 19.2MHz OSC on RPi0-3 which is fine for 8kHz and 16kHz at 24bit...
by HiassofT
Fri Apr 24, 2020 8:10 pm
Forum: General discussion
Topic: Update to default Pi4 bootloader
Replies: 54
Views: 5949

Re: Update to default Pi4 bootloader

I've updated 2 of my main RPi4s to stable pieeprom firmware today and no showstoppers to report so far - both SD card boot and TFTP netboot are still working fine.

so long,

Hias
by HiassofT
Thu Apr 16, 2020 1:31 pm
Forum: Advanced users
Topic: Moving Linux Kernel to 5.4
Replies: 335
Views: 40658

Re: Moving Linux Kernel to 5.4

FWIW: my cirrus logic audio card, which uses SPI for communication with the WM5102, is working fine with the 5.4 kernel (both on LibreELEC and Raspbian). Haven't checked with the TV hat though, but at least SPI is not completely broken :)

so long,

Hias
by HiassofT
Tue Apr 14, 2020 9:25 am
Forum: General discussion
Topic: Annual running cost of RPi4?
Replies: 13
Views: 716

Re: Annual running cost of RPi4?

About a year ago I checked secondary power consumption on the RPi4 and the maximum I saw during a "make .-j 4" kernel build was about 5.7W (this was well before all the power/thermal optimizations we've seen in the last year). So a rough estimate of max 7-10W primary/mains power consumption seems mo...
by HiassofT
Wed Apr 08, 2020 2:02 pm
Forum: Advanced users
Topic: Moving Linux Kernel to 5.4
Replies: 335
Views: 40658

Re: Moving Linux Kernel to 5.4

Stack protection is a compiler feature that helps to guard against buffer overflows. SMP stands for Symmetric Multi Processing, which you can think of as support for multi-core platforms (which BCM2836, BCM2837 and BCM2711 are, but BCM2835 isn't). The commit is saying that the old way of doing stac...
by HiassofT
Sat Apr 04, 2020 8:22 am
Forum: Advanced users
Topic: Moving Linux Kernel to 5.4
Replies: 335
Views: 40658

Re: Moving Linux Kernel to 5.4

and you should havea new alsa device. (Only available when running with dtoverlay=vc4-kms-v3d-pi4). Dual HDMI audio should work from the driver level. Is it a case of replicating the vc4-hdmi.pcm.hdmi.0 section as vc4-hdmi.pcm.hdmi.1? (I was just going to try it, but the TV I have as a second monit...
by HiassofT
Thu Apr 02, 2020 9:15 am
Forum: Advanced users
Topic: PXE-BOOT RPi4. What am i missing?
Replies: 14
Views: 545

Re: PXE-BOOT RPi4. What am i missing?

The contents of option 66 (tftp server name) look odd: Option: (66) TFTP Server Name Length: 15 TFTP Server Name: 192.168.88.6/24 If present this should contain the IP address of the dhcp server (eg 192.168.88.6, without the /24 at the end). IIRC DNS isn't implemented in the firmware so we can't use...
by HiassofT
Mon Mar 30, 2020 5:42 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread. [I2S works]
Replies: 984
Views: 530634

Re: STICKY: The I2S sound thread. [I2S works]

It's not problem to transfer data with more bclk cycles than valid data bits, the I2S block will automatically pad them. Just use the set_bclk_ratio or set_tdm_slot functions to set that to eg 64 bclk cycles per frame.

so long,

Hias
by HiassofT
Sat Mar 21, 2020 12:58 pm
Forum: Device Tree
Topic: Updated Device Tree documentation
Replies: 11
Views: 920

Re: Updated Device Tree documentation

Thanks a lot for the massive change, updated docs are highly appreciated!

Small nit in section 2.1: the first example and the compatible description were updated to brcm,bcm2835, but the interpretation below and fdtdump output still have the old bcm2708 compatible string.

so long,

Hias
by HiassofT
Fri Mar 20, 2020 11:19 am
Forum: Advanced users
Topic: Raspberry Pi4 bootloader - network boot support - BETA
Replies: 90
Views: 30756

Re: Raspberry Pi4 bootloader - network boot support - BETA

Thanks for the info!

I was mainly wondering about the "outdated firmware" comment as that suggested that something might have changed at some point.

so long,

Hias
by HiassofT
Fri Mar 20, 2020 9:51 am
Forum: Advanced users
Topic: Raspberry Pi4 bootloader - network boot support - BETA
Replies: 90
Views: 30756

Re: Raspberry Pi4 bootloader - network boot support - BETA

A quick heads-up: I tested netbooting with the 5.4 kernel and while tftp boot was fine (both with stable and beta pieeprom firmware) network operation in the kernel was very flaky. Some time kernel IP configuration didn't succeed (with no DHCP request packets showing up in tcpdump) or if it succeede...
by HiassofT
Thu Mar 05, 2020 2:11 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: How to connect the REMOTE OUT port of an amplifier to a Raspberry Pi?
Replies: 4
Views: 727

Re: How to connect the REMOTE OUT port of an amplifier to a Raspberry Pi?

More likely the Marantz amp uses non-inverted / active-high signalling - standard IR receivers use inverted / active-low signalling and the gpio-ir overlay configures the GPIO for that. I've opened a PR to make that configurable via an "invert" parameter (eg use dtoverlay=gpio-ir,gpio_pin=5,invert=0...
by HiassofT
Wed Feb 26, 2020 4:29 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread. [I2S works]
Replies: 984
Views: 530634

Re: STICKY: The I2S sound thread. [I2S works]

would you mind checking my earlier posts regarding dynamic master/slave usage? I don't think dynamic switching between master and slave mode is going to work this way. Just create two overlays (one for master, one for slave) and use the "dtoverlay"/"dtoverlay -r" commands to load/unload them during...
by HiassofT
Sun Feb 23, 2020 10:05 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread. [I2S works]
Replies: 984
Views: 530634

Re: STICKY: The I2S sound thread. [I2S works]

The convert-rate/convert-channels properties can only be used with hardware that has a sample rate converter built in. The only one I know of that's using this is renesas - see https://github.com/raspberrypi/linux/blob/rpi-5.6.y/Documentation/devicetree/bindings/sound/renesas%2Crsnd.txt In earlier k...
by HiassofT
Fri Feb 07, 2020 6:37 pm
Forum: General discussion
Topic: RPi 4 audio bit rate and sample rate
Replies: 13
Views: 1326

Re: RPi 4 audio bit rate and sample rate

That's a rather old post you linked to, predating the kernel commit which added support for 384kHz on RPi. Basically any pcm512x based soundcard will support 384kHz. Just dug out my JustBoom DAC and it worked fine: pi@raspberrypi:~/audiotest $ aplay -v -D hw:sndrpijustboomd 384-32.wav Playing WAVE '...
by HiassofT
Thu Feb 06, 2020 11:47 pm
Forum: General discussion
Topic: RPi 4 audio bit rate and sample rate
Replies: 13
Views: 1326

Re: RPi 4 audio bit rate and sample rate

All RPis support up to 384kHz stereo at 32bits resolution via I2S - see https://github.com/raspberrypi/linux/commit/675c0ee514f56ea39f6f550299621aafe9a53fc0 Other than that (and before this thread degrades into an audiophool flamewar) I'd recommend everyone to re-read Monty's older but still excelle...
by HiassofT
Thu Feb 06, 2020 5:44 pm
Forum: General discussion
Topic: IR Receiver Solution
Replies: 12
Views: 586

Re: IR Receiver Solution

If you are using the rc subsystem for decoding (i.e. ir-keytable configuration) you could use the linux LEDs and the rc-feedback trigger. eg (run as root): echo rc-feedback > /sys/class/leds/led0/trigger lets the ACT LED light up whenever a valid button is being received. You could also register you...
by HiassofT
Thu Feb 06, 2020 4:00 pm
Forum: General discussion
Topic: IR Receiver Solution
Replies: 12
Views: 586

Re: IR Receiver Solution

You could try replacing the IR receiver with an original Vishay TSOP 34438 and only use the cable+case of this one.

I've got a couple of similarly looking IR receivers (in the metal can like yours) from asia and they perform really poorly compared to the Vishay ones.

so long,

Hias
by HiassofT
Wed Feb 05, 2020 9:13 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread. [I2S works]
Replies: 984
Views: 530634

Re: STICKY: The I2S sound thread.

Easiest way would be to create a DT overlay for simple-audio-card (or audio-graph-card) and use that instead. Just search this subforum and/or thread, I'm pretty sure I already posted info about that before.

so long,

Hias
by HiassofT
Mon Jan 20, 2020 8:28 pm
Forum: General discussion
Topic: Future of raspberry pi - software related
Replies: 382
Views: 36444

Re: Future of raspberry pi - software related

OK, so have read back through the thread, and this is my curated list so far. ... Nice long list :-) One item, which I've been waiting for since the very first RPi was released, is missing though: proper upstream Kernel and Debian support (the latter should come automatically with the former). so l...
by HiassofT
Fri Jan 17, 2020 2:35 pm
Forum: General discussion
Topic: Future of raspberry pi - software related
Replies: 382
Views: 36444

Re: Future of raspberry pi - software related

’d rather see performance wrung out of ES 2.0 on VC4 and ES 3.2 on VC6 before turning to other pastures. I have little need for desktop OpenGL support, per se, since my project is new and targeting Raspian. I wonder what focus is a priority for others? I don't care too much about Vulkan or GL, but ...
by HiassofT
Fri Jan 17, 2020 2:16 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: I2S clock rate question
Replies: 2
Views: 281

Re: I2S clock rate question

ics43432 only supports 7190-52800Hz, see here https://github.com/raspberrypi/linux/bl ... .c#L22-L23

I'd recommend you try with the generic spdif receiver codec (linux,spdif-dir compatible) similar to what you're already using for output.

so long,

Hias
by HiassofT
Thu Dec 26, 2019 8:16 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: STICKY: The I2S sound thread. [I2S works]
Replies: 984
Views: 530634

Re: STICKY: The I2S sound thread.

i'm Raspy beginner ia have a question: i' ve read in the BCM 2835 datasheet "Jitter is therefore reduced by increasing the source clock frequency. In applications where jitter is a concern, the fastest available clock source should be used." I' ve found o a Isotemp OCXO Clock but the frequency is 1...
by HiassofT
Tue Sep 24, 2019 10:48 pm
Forum: Advanced users
Topic: Raspberry Pi4 bootloader - network boot support - BETA
Replies: 90
Views: 30756

Re: Raspberry Pi4 bootloader - network boot support - BETA

I did some tests with a RPi behind a wifi bridge (typ. 10MB/sec net bandwidth with TCP) on a different subnet than the TFTP server, netbooting current LibreELEC 9.2 dev version. First test went fine, so TFTP on different subnet seems to be no issue, but the TFTP_FILE_TIMEOUT default seems to a bit m...

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