Armbian tv box setup. By jock January 8, 2020 in Rockchip CPU Boxes.

Armbian tv box setup I have successfully installed Armbian on my TV box. It uses NAND storage and it seems has some very specific configurations needed in the fex which are custom (thinking possibly very low DRAM settings or some specific After installing the system in eMMC, immediately from the system running from the SD card, mount the EMMC root partition and perform a personal configuration for a specific instance of the TV box (for example, creating a new user, changing passwords, setting a static IP address, MAC, system name, etc. 67_Rk3328-tv_Ubuntu_bionic_default_4. I have tested the images from Google Drive: Armbian 5. I bought myself a stack of four tv boxes to play with each with different processors. rk3328-a5x. txt like you told to do and, unfortunately, the freezing still happening. I mean a list with references to the dtbs used to success and The Android TV box I would like to install armbian on say T95 on the top but inside on the board it says S905-248G-6330. With apt-get it should be quite possible to get the kernel sources and everything that is needed to do the job, providing he is using a stable image from CSC Armbian for RK322x TV box boards CSC Armbian for RK322x TV box boards. Русский (RU) 简体中文 . It does not depend upon the market name of the tv box and neither the internal board; manufacturers put whatever they find cheaper when they buy the components. It has an Amlogic CPU I do all the process of installing Armbian in the SD card, Android starts an update and it says: "M x64 machine with at least 2GB of memory and ~35GB of disk space for the VM, container or native OS, Ubuntu Focal 20. To ensure the setup worked, I connected the TV box to a Windows computer using a USB-to-Serial adapter ( using my Arduino uno for this shorting the reset and GND together to by pass the chips mcu ) and monitored the Armbian for TV box rk3328 Armbian for TV box rk3328. Can't say anything more, stmmac_open hw setup failed + some DMA setup failures 'ip a' shows an interface named eth0, but 'ethtool eth0' gives some errors as well. You setup two screens there. RKdumper wouldn't work. Posted January 2, 2022. 59 and 5. Connect this media to a "dirty" TV box, run Armbian, and restore the copy from the ddbr utility. Run as user "root" script "/boot/create-mbr-linux. It also turns out my TV box was a little bit faster than my main "server" the PineA64 board. Looks like that there is a new board version of this TV Box and unfortunately the Armbian images existing for R69 didn´t work for me. e. 4/5. 04 x64 for native building or any Docker capable x64 Linux for containerised, superuser rights (configured sudo or root access). txt and see if you advance in getting bluetooth: broadcom chips have the need for some bits in the device tree to load the driver and attach the communication $ cd armbian-build $ . dtb no eth0 rk3328-box. Quote; suryob. 0-trunk_Xt The Reread my log analysis of Xorg. ( Board is permanent in Maskrom Mode now) The Booting Problem here is, this new box is not the same. The answer is quite simple although: for historic reasons, those overlays are called led-conf but actually, during time and studies on the boards, they should be more It is still a work in progress for the mainline kernel, hopefully when all the bits will be in place it will be even better. So far I am only having luck with RK3318 mainline and the rk3328 legacy Station M1 builds. By balbes150 August 30, 2018 in Rockchip CPU Boxes. Hello, Thank you for this amazing project. 3. You are on current 6. Armbian is suited mostly for linux desktop replacement and server-like tasks. Hello, and Thank you @SteeMan indeed I didn't take the good way . One driven via modesetting with the 3D render node (card1) as the display subsystem with no scan-out hardware. 1. The latest kernel update for my TV box (linux-image-legacy-rk322x_23. The script will take care about preparing the workspace I thought of using the multitool to burn an image to the tv box, but after picking an image and inserting the sd card, it did not respond, since it booted from the original firmware and ignored multitool. It truly revived this old TV Box from the dead. English (USA) (Default) Deutsch . Download armbian-build and apply the patch: A quick msg to kindly ask what should be the current kernels with an RK3318/28 TV Box. Most likely, your DTB doesn't have support for the SD card. 5 or below (remember it's only dual core system, running almost same software configuration except it's using latest mainline stable Kernel 5. log. img + rk3328-evb. 62_20225, the picture is the MASKROM pads, in my board i put a switch button to do easy, this board enter in MASKROM mode when hold on jumper in pads and conect USB cabe in compunter! this is just a quick note that in my experience the amount of tv boxes with fake specs has grown quite a bit in the last months and that this is something to always have in mind when getting a box for a surprisingly cheap (i. y). I was curious about this chip after I saw a Picture of the Rock64 here on Armbian. Use the default The question is absolutely relevant and very welcome. I disabled the build of many drivers that, in my opinion, will not be used on a TV-box. 0-rc1. Share Pulseaudio also has some issues with labels, but I2S should be in reality HDMI (on my setup both SPDIF and HDMI appears as "Analog audio" ) Some trick you may try: 1) Disable compositing from Menu -> Settings @SteeMan Thank you for the advice!. 0 Smart TV Box Spezifikationen Betriebssystem: Android 11. Ground of Serial port on PC -----> Ground of TV Box RX (input) pin of Serial port -----> TX (output) pin of TV Box You don't need to send the data from PC to the TV Box (at this moment). I can't fathom the effort it has taken to get to here! I have a Sunvell T95Z plus with a S912 processor. /rebuild -d -b s905x3 -k 5. The load average in that TV box is very often 0. img from @balbes150 and using the snap installations, successfully set up NextCloud on my MX10 (RK3328) ver: 1. Surely the gpu part is easier to setup and use (it works out of the box) due to being backed by mesa instead This was necessary to use the port for sending commands to the Arduino without interference from the TV box’s system. Can CSC Armbian for RK322x TV box boards CSC Armbian for RK322x TV box boards (include SOC RK3229, RAM K4B2G0446D, Wi-fi SV6051P, this TV-Box Iconbit XDS8) works with the image Armbian_20. [ 0. Share putting it in rk322x-led-conf-default. Share How is the params file stored in your setup and how can we modify it. Share Was renaming the original file and putting the new one in the same place and running rkconfig with the same settings and then sync and reboot and its not loading the setting = no HDMI. /rebuild -d: Use the default configuration to pack all TV Boxes. Hi, I'm quite new to all this Linux Arm thing and I don't have any setup to create the build myself. . @sadp Your wifi chip is not supported by the brcmfmac driver; there is a patch for rockchip64 family but not for rk322x. 000000] cma: Reserved 16 MiB at 0x9f000000 on node -1 Setting up static identity map for 0x60100000 - 0x60100060 [ 0. This is only if its OK for all other board but i think its I have a MX10 Pro TV box I have been trying to get working with the dreaded SV6051 wifi. I can boot Armbian_20. sh. 1_armhf After modifying the rk3318-config script, it now detects my WiFi card and configure Bluetooth! (maybe another lookup path should be added in rk3318-config?) Yes, you're right! In the thread about CSC Armbian for RK322X TV Boxes, good news about Multitool with SSH, This Multitool is suitable for rk3318 ?? What version of drrbin is there? The Box is as follows: RUPA Android TV Box, 4K TV Box 11. 0 3D 4K 1080P10/100M Ethernet HD2. My system is currently on -edge and having 6. Find the one that best Purchase Link This should be a fun one. img A place for discussion of TV Boxes using Amlogic CPUs (s905, s905x, s905w, s912, s922, etc) 3. I don't know what the problem is. mr. sh BOARD=rk322x-box BRANCH=legacy RELEASE=focal BUILD_MINIMAL=yes BUILD_DESKTOP=no KERNEL_CONFIGURE=yes INSTALL_HEADERS=yes There is no need to activate multi-boot (make changes to the regular firmware to run Armbian). CSC Armbian for RK322x TV box boards CSC Armbian for RK322x TV box boards and is everything ok with it, I have two bought together with the tv box weeks before this post Burn the image several times. 07_Rk3328-tv_buster_current_5. @zero - welcome to the wonderful world of fake tv boxes Hi all. Thanks to your message, I changed my approach and I succeeded starting from Armbian_20. 46 without success, the same for RetroOrangePi R69 image. The installation is aborted at the file copying stage (message "Cleaning up Almost done", but the tv box does not start with emmc). Therefore, you can launch Armbian from an external media on a "clean" TV box (with Android). dtb no eth0 rk3328-a5x-1500. Download armbian-build and apply the patch: @audio kees if your need is just play video at 4k you probably won't go with armbian but rather with libreelec; if your goal is playing music you'd probably want to go with volumio either. I burned Armbian before on a different RK322x box and all went fine. 44_mate_desktop. By jock January 8, 2020 in Especially for you I did also setup a wireguard-tunnel to my bannana pi (also running armbian) most of the rk322x tv boxes are advertised as 1. 8. 4 kernel. Burning the image "Armbian_23. 1. 0 lunar and bookworm), changed the /boot/ArmibianEnv. NAND chip is just the non-volatile memory hi, I am considering getting a couple of inexpensive tv boxes to play with, my goals in order of interest would be: - Test Linux running some monitoring bash scripts. - Test Linux running some lan services as PiHole, nginx service fallback static pages for a couple of domains. 194, xfce, on my box everything works fine, only Youtube, it works slow, I appreciate your response. 100: recommend. 1 Bookworm Minimal. When I saw this page (thanks @Hqnicolas) - looked at the specs of this board, and looked at its price ($85) - I knew I had to try to install Linux on it. There are very limited people resources working on Armbian (and even less with TV boxes). Once you are done configurion your OS, you can proceed to software section. The only link to the stock firmware I can find is dead and in addition the board doesn't seem to switch to recovery mode by pushing the button (no USB device pops up). 0-trunk. Wif CSC Armbian for RK322x TV box boards CSC Armbian for RK322x TV box boards. It should be as easy as booting from SD card, updating everything with 'apt upgrade' and then executing nand-sata-install. 5 Ghz, but in reality rk3229/rk3228b chips are safe up to 1. So right value for the ram is set item default (that don't specifies the frequency value). BTW, you may wish to try to enable box-wlan-ap6330 or box-wlan-ap6334 device tree overlay in /boot/armbianEnv. 0_driver_as_rockchip. dtb > meson-g12b-ugoos-am6. 000000] OF: fdt: Machine model: Generic RK322x Tv Box board [ 0. And a pico second is a dammed short time. 4. By jock January 8, 2020 in [ 0. You are asked to set a root password, normal user and confirm your, automatically determined, language settings. The right values depend on used chips and pcb layout and must be I had seen it, but It refers to tv boxes booting armbian, with lots of issues that are solved at this moment. 5. Sometimes they call it "format", where you can select 16:9, 4:3, "just scan", zoom, and other options. Thank you for your clarification . sh docker-shell . 4. RK3228 and RK3229 tv boxes comes with three different flash memory chips: eMMC, NAND and eMCP. 05. Said so, tv boxes are the worst choice around in any case, especially if you choose among the Hello @victroniko, very glad you find our work useful!. open ones , SD-Card , USB and NAND boot allow , boot SD-CARD/USB also if there a OS in NAND or install Armbian legacy to nand. AP6330 Wifi Stock software is a really, really bad Android TV port. I tried out an old usb wifi dongle I had, and a really old BT dongle I had and both of them worked on my A5x Max box with Armbian_5. Using any of the following dtb files: M Bootloader update only possible with male - male USB cable and rktool outside of the box there are 3 bootloader 1. in case anyone (maybe @kalikopfnuss maybe others too) wants to give this approach a try on such a box or maybe even on other not yet working allwinner h6 boxes - just get the latest rk aml aw image from @balbes150 from here: Module Size Used by hci_uart 34102 1 cifs 402687 0 bnep 15079 2 Hello guys! @jock, I burned another image in the SD card (Armbian 23. 2. Loving this project. Armbian fluid (Default) Armbian fixed . 5. 143_desktop_20181203. Run the ddbr utility and create a full compressed copy of eMMC. 16. Its a Giga TV Box HD890 4K. It does not have a reset button but has an update app. 2. 0 Chipsatz: RK3318 Quad-Core 64bit Cortex-A53 GPU: Penta-Core Mali-450 FLASH: EMMC 64 GB RAM: DDR 4 GB USB: 1 x USB Hello, I have installed the armbian bookworm version with xfce on it, 6. dtb no inet rk3328-box-trn9-1500. Bought the 4GB/128GB variant. By jock April 16 (especially for raspberry pi) on how to setup a gadget, you can use them to actually test the port. /compile. With an unfolded paperclip, press the reset button; While holding the reset button, plug the power To install the Armbian image to your TV Box’s internal eMMC memory from a running microSD card image, run the Armbian configuration utility from the desktop and select Now, you can replace the Android TV system on your TV box with the Armbian system, turning it into a powerful server. dtb no eth0 rk3328-box-liantong. dtb I am trying to install Armbian on emmc of the tv box X96Q using armbian-install. img" in "/boot/uboot. Armbian for tv box Z28 Language . 037_Aml-s9xxx_bionic_current_5. Firstly, I want to share my experience with my my board (HK1 Mini), which might be useful to others. Well, it looks like there's another wifi chip in the cauldron of rk322x boxes . 11. dts then the user is getting HDMI working from beginning and dont need struggling setting it up with SSH or terminal. 1 right now, so perhaps you may want to switch when the new kernel will this box i would not recommend: one i got was in the end 2+16g instead of the promised 4+32g - furthermore the allwinner h6 u-boot is not booting it (maybe some new memory timing issues - the cpu is a h6 for sure, i I have two TV boxes that I installed armbian on them and recently I made an update / upgrade to both of them but only one seems to be unreachable. With legacy image (even on orange pi pc) I never get stability running pi-hole,either pihole web server ran but TV box + LInux CNC. Note: If you have previously run other distributions on the box such as coreelec the below installation will not work. @pakos96 from the dmesg you posted there is a problem with the sdio wifi too (device mmc1), so there is something wrong with your configuration which is disrupting the mmc controller as a whole. 8Ghz BT4. img to an SD card with Rufus and then again with Belena Etcher, but the TV box wont start with the SD card inserted, although when I say it doesnt boot. To do this, Also be prepared if anything goes horribly wrong with your emmc install to reinstall the android firmware using the Amlogic USB Burning Tool to unbrick your device. After the script has Insert microSD card to Android TV box; Booting to Armbian for the First Time. 02. 8k An area for discussing general topics about Armbian on TV Boxes 11k posts. The board itself is 4GB ram and 64GB eMMC and everything is working other than the wifi. If the system works correctly and you are satisfied, run the utility "ddbr" and create a full backup of eMMC (this is a prerequisite). ). My TV box has a 6051p network card. Had to fix that on my monitor/TVs usually setting the right option in the menu (some call it "16:9", some "Just Scan", "PC mode" or other fantasy names), but never had to handle it at board level. First things first - I did an Android backup. I have done this setup with an rk3318 box and this armbian distro. sh" 6. dtb no inet rk3328-box-z28. I noticed some thing at these new tries: 1 - In both cases (Burned Image or Multitool) the board still alive for only 60s. CSC Armbian for RK3288 TV Box boards (Q8) CSC Armbian for RK3288 TV Box boards (Q8) By jock May 6, 2018 in Rockchip CPU Boxes. sorry for late answer you have to try some LED-Config ( better name GPIO Config) settings inside rk322x-config tool and always reboot after every No, there's no NAND in this box and none of all the outdated NAND related stuff applies to ANY H3 device. CSC Armbian for RK322x TV box boards CSC Armbian for RK322x TV box boards. Contribute to indiboy/amlogic-s805-armbian development by creating an account on GitHub. Run sudo armbian-config to configure timezone, locales and other personal options Congratulations, Armbian is now installed and configured! CSC Armbian for RK3318/RK3328 TV box boards CSC Armbian for RK3318/RK3328 TV box boards. 7. 30 kernel on my 32gb usb flash drive using balena etcher according to the instruction, I have tweaked the boot. Armbian config tool helps you configure your network (static, dynamic, enabling hotspot). sh script by issuing the following command: . I think it is clear how to connect the CSC Armbian for RK322x TV box boards CSC Armbian for RK322x TV box boards. 4 Ghz and rk3228a chips are safe CSC Armbian for RK3288 TV Box boards (Q8) CSC Armbian for RK3288 TV Box boards (Q8) By jock May 6, 2018 in Rockchip CPU Boxes but TVs have the overscan setting which is pretty annoying (and IMHO obsolete nowadays). 086991] CPU0: thread -1, cpu 0, socket 15, mpidr 80000f00 [ 0. img. If you have or can find an original android firmware on the This Armbian configuration is based on the one for hinlink-h28k, which is the first RK3528 device in Armbian. I'm learning a ton about the A20 and linux, this is quite a change from my daily "co Do you happen to have a link to said image? Armbian_23. 000000] Memory policy: Data cache writealloc [ 0. @helix afaik, no tool for that. dtb system not start rk3328-box-trn9. You will need to restore the original android firmware The guide was created in response to the outdated or non-functional nature of much of the software provided by armbian-config->Software->Softy, particularly for TV boxes. This should install Armbian onto your TV box. CSC Armbian for RK3318/RK3328 TV box boards Language . 0, with LAN access In the past with Allwinner H3 based TV boxes it was rather easy to get them supported in Armbian since it was reading out the proprietary fex stuff and then adjusting few bits. Armbian is suited mostly for linux I'm testing Beelink Debian Strech 4. 1_Rk322x-box_bookworm_current_6. Start Armbian on the TV box and perform the initial setup of the system. Some parts report the device as Pixel 5, others MX10. 52_Aml-s9xx-box_lunar_edge_6. madness: 6051p network card. 50. To do this, there are 2 files on the SD card or USB stick you create. If you plan to use your board for running a home CSC Armbian for RK3288 TV Box boards (Q8) CSC Armbian for RK3288 TV Box boards (Q8) So, it seems, some X11 setting isn't quite right - because intentional changing of refresh rate causes the same defect. Looks like a Google Pixel 5 image that has had RK3528 support hacked into it. 087096] Setting up static identity map for 0x60008280 - 0x600082d8 [ 0. 11 installed, but reading here that doing an upgrade on edge, people are I flashed Armbian-unofficial_24. dts And you get the device tree in a text file, see attachment. open ones , SD-Card USB Boot NAND boot allow but boot NAND first , there you can try the new point in Multitool The module can be enabled in all the kernels if it is needed, but @microsolar can compile the kernel module for his own kernel too following the debian/ubuntu instruction on how to enable and compile kernel modules. Yes, I tried all the dtb files of rk3328, now again. Cortex-A7 Quad-Core - Mali-400, supports? How do I Enable i2c2 on Armbian 24. By jock January 8, 2020 in Rockchip CPU Boxes. xz" with Multitool seemed to go well. Do not include spaces when setting custom signatures. Armbian config provides clean and fast way of installing great selection of popular software titles. Support 玩客云。. a query this package will work for rk322x boxes, Armbian buster installed system, legacy kernel 4. If your hardware has An effective tutorial from @Hai Nguyen on how to configure a box as a hi-quality music player using an USB audio card, You can build your own image follow the common steps to build armbian for other tv boxes devices: When you set up Armbian on a Android TV box, you need to tell Armbian what drivers/setup to use for the chipset in your box. Armbian for tv box Z28 Armbian for tv box Z28. Plug the power adapter into the Android TV box; You should see the Armbian terminal running startup scripts; Insert microSD card to Android TV box; Booting to Armbian for the First Time. This is done through matching the best DTB file to your TV Box’s hardware. The board silkscreen is labeled as MXQ-RK3328-D4_A VER: 1. In terms of performance I bought a brand new Q96max 4k Ultra HD TV Box for the sole purpose of burning Armbian to it. The kernel config is a mix of the configs from the preinstalled Android and the config for hinlink-h28k. Found some informations about the ESP8089 on the linux-sunxi site which points to this other repository that already has some kernel integration and, most of all, the firmware files. Posted April 4. Русский (RU) Theme . dtb no eth0 rk3328-evb As I say, only on THIS build of Armbian and THIS MeCool box, hence setting up RDP. dtb no eth0 rk3328-evb. - Test Linux acting CSC Armbian for RK322x TV box boards CSC Armbian for RK322x TV box boards. This project relies on many contributors to build the Armbian system for Amlogic, Rockchip, and Allwinner boxes, Basic OS configuration is conducted at first boot. Can anyone help me turn this into a armbian server to run Klipper on please? I have pictures of the board but not sure how to For comparison, I am running Armbian on another Cubieboard 2 compatible TV box (1 GB RAM, CPU SoC is Allwinner A20 dual core A7 @ 1 Ghz). It is tailored for advanced users who are Log into your box with the root account and run the install-aml. 0. Armbian for Amlogic s805 tv box. Share (burn an image to two SD+USB media at once, configure it, and connect them simultaneously). @rafman please share the image (or the path) with a secure boot for the tv box X96Q or Z1 Do you happen to have a link to said image? Armbian_23. 0-rc6_desktop_20200205 from SD card. Could be done for the legacy Allwinner kernel even without having the device in front of you (see Sunvell R69) but the situation with boards based on the new BSP is . rather, do not work fully. 0-trunk_X96q_bookworm_current_6. Rename the file "/boot/mvr9-uboot. 6. I do all the setup from a Windows machine and that's mostly why I haven't got a proper setup to try my own build. Session is indeed terminated, the control button on the TV box lights first red and then blue - as it is it possible for rk322x tv box to enable the OTG port on this one and make use of USB gadget? 0. Armbian Hi, i want share the experiences with my MXQ_R2B_LP3_V2. 10. With dtc tool you can also get the dts (text) from the dtb (binary) $ dtc -I dtb -O dts meson-g12b-ugoos-am6. These instructions are for Amlogic CPUs for TV Boxes. By jock January 8 I’ll probably try to heap all the information on these Tv-boxes, maybe they will need a separate dtb for them. and when I tried booting on the tv, everything worked till bam it kernel To add my own reason to the above list of reasons to use the TV boxes, It is a simple use case, and I get to keep a TV box out of the electronic heaven in the sky for a little longer, and save a new purchase. It has an Amlogic CPU I do all the process of installing Armbian in the SD card, Android starts an update and it says: "M I tried out an old usb wifi dongle I had, and a really old BT dongle I had and both of them worked on my A5x Max box with Armbian_5. cmd file, and only tweaked the video settings and regenerated using the mkimage command, Using linux to setup. The box ran fine on Android. 0 RAM 8GB ROM 64GB RK3318 Quad-Core CPU WiFi 2. Share . then back and select Keyboard and select your correct This Armbian configuration is based on the one for hinlink-h28k, which is the first RK3528 device in Armbian. That's my other problem. ===== 1. /install-aml. sudo . dtb no eth0 rk3328-a5x-mx10. sh build BOARD=onn4k BRANCH=current BUILD_DESKTOP=yes BUILD_MINIMAL=no DESKTOP_APPGROUPS_SELECTED= DESKTOP_ENVIRONMENT=mate DESKTOP_ENVIRONMENT_CONFIG_NAME=config_base EXPERT=yes KERNEL_CONFIGURE=no KERNEL_GIT=shallow RELEASE=bookworm Some Time ago I bought a cheap Z28 TV Box fromGearbest for 27€. @remlei very true 1/8G can running but best mounting one SD-card for docker data so all HA containers is being out of the eMMC then its being full then HA is installed and booting up for the first time also USB is tricky and need repower for getting disconnected device being reconiced after some time but they is working pretty good for no production systems. img @audio kees if your need is just play video at 4k you probably won't go with armbian but rather with libreelec; if your goal is playing music you'd probably want to go with volumio either. I managed to integrate it very easily into Hi, I would like to know if its possible to boot from SD card in my model of Android TV BOX. These numbers count in pico seconds. phandles are the way how kernel navigates the device tree. Theme . Both TV boxes are identical excpet one of them has piHole insalled. When you set up Armbian on a Android TV box, you need to tell Armbian what drivers/setup to use for the chipset in your box. dtb Hi, I would like to know if its possible to boot from SD card in my model of Android TV BOX. With your cursor keys, go down to the Personal menu, select Timezone and choose your region. Regarding klipper and rk3318/rk3328. I have made trial setting 660 mhz as frequency ram but sometimes don't boot. 13 server image on the R69. I will make a Pull Request to add the patch for rk322x but have to be patient, wait a couple of weeks and it will be probably available for edge 6. img". Quote; Netraam31. Hats off to Balbes150 and all. You can use the keyboard cursor keys, TAB key to move around each screen and Escape will move you back a screen. quite a bit cheaper than usual or most of the other offerings) price - you might be lucky and it will be a bargain or you might hit one with fake CSC Armbian for RK322x TV box boards CSC Armbian for RK322x TV box boards. Fehler beim Bearbeiten des Paketes console-common (--configure): Abh ngigkeitsprobleme - verbleibt unkonfiguriert Fehler traten auf Regarding dram settings. However, the WiFi is not working, only the Ethernet cable connection. Turned on Android box. By Da Alchemist July 14, 2017 in so perhaps some Voltage settings are not quite right. Results are very satisfying for my use case. zmxw byofhh yosvn ums ker otj uqlkk vms cnwkp uycosk