星期二, 2月 14, 2023

What Is a Thread Border Router? (And Do I Need to Buy One?)

What Is a Thread Border Router? (And Do I Need to Buy One?)

 


At the time of writing in September of 2022, for example, the following pieces of smart home hardware already have Thread border routers built into them:


Reference:

https://www.howtogeek.com/830124/what-is-a-thread-border-router-and-do-i-need-to-buy-one/

星期五, 12月 09, 2022

H.264 NAL reference

 http://www.hellotongtong.com/avcodecbase/avcodecbase-h264-learning100.html

    1. forbidden_zero_bit
      1. bit,H264 规定此位必须为 0
    2. nal_ref_idc
      1. 用于表示当前 NALU 的重要性,值越大,越重要
      2. 解码器在解码处理不过来的时候,可以丢掉重要性为 0 的 NALU
      3. nal_ref_idc 不等于 0 时, NAL unit 的内容可能是 SPS/PPS/参考帧 的片

        nal_ref_idc 等于 0 时,NAL unit 的内容可能是非参考图像的片

        当某个图像的片的 nal_ref_id 等于 0 时,该图像的所有片均应等于 0



            星期四, 12月 08, 2022

            ffprobe h264

             ffprobe -show_frames 1.h264 |grep pict_type

            jack@i7-build-server:~$ ffprobe -show_streams 1.h264

            星期五, 11月 25, 2022

            CPython

             Cross-compile Python for use on armv7l


            Cross compiling python for aarch64


            #!/bin/bashset -x -eexport HOST_ARCH=aarch64-linux-gnuexport TOOL_PREFIX=/home/username/aarch64-linux-toolchain/bin/$HOST_ARCH
            export CXX=$TOOL_PREFIX-g++
            export CPP="$TOOL_PREFIX-g++ -E"export AR=$TOOL_PREFIX-arexport RANLIB=$TOOL_PREFIX-ranlibexport CC=$TOOL_PREFIX-gccexport LD=$TOOL_PREFIX-ldexport READELF=$TOOL_PREFIX-readelfexport LDLAST="-lgcov"./configure --host=$HOST_ARCH --target=$HOST_ARCH --build=x86_64-pc-linux-gnu --prefix=$HOME/temp --disable-ipv6 ac_cv_file__dev_ptmx=no ac_cv_file__dev_ptc=no ac_cv_have_long_long_format=yes --enable-shared --with-zlib-dir=/usr/lib64 --with-ensurepip=yes --enable-optimizationmake BLDSHARED="$TOOL_PREFIX-gcc -shared" CROSS-COMPILE=$TOOL_PREFIX- CROSS_COMPILE_TARGET=yessudo make install BLDSHARED="$TOOL_PREFIX-gcc -shared" CROSS-COMPILE=$TOOL_PREFIX- CROSS_COMPILE_TARGET=yes prefix=$HOME/Python-$HOST_ARCH/_install

            星期四, 11月 17, 2022

            星期五, 11月 04, 2022

            bitmap font

             

            1.https://github.com/dhepper/font8x8

            2. https://opengameart.org/art-search?keys=bitmap

            3. https://opengameart.org/content/8x8-ascii-bitmap-font-with-c-source



            /************************************************************************

            * font.c

            * Copyright (C) Lisa Milne 2014 <lisa@ltmnet.com>

            *

            * This program is free software: you can redistribute it and/or modify

            * it under the terms of the GNU General Public License as published by

            * the Free Software Foundation, either version 3 of the License, or

            * (at your option) any later version.

            *

            * This program is distributed in the hope that it will be useful, but

            * WITHOUT ANY WARRANTY; without even the implied warranty of

            * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

            * See the GNU General Public License for more details.

            *

            * You should have received a copy of the GNU General Public License

            * along with this program.  If not, see <http://www.gnu.org/licenses/>

            ************************************************************************/


            /* the values in this array are a 8x8 bitmap font for ascii characters */

            static uint64_t font[128] = {

            0x7E7E7E7E7E7E0000, /* NUL */

            0x7E7E7E7E7E7E0000, /* SOH */

            0x7E7E7E7E7E7E0000, /* STX */

            0x7E7E7E7E7E7E0000, /* ETX */

            0x7E7E7E7E7E7E0000, /* EOT */

            0x7E7E7E7E7E7E0000, /* ENQ */

            0x7E7E7E7E7E7E0000, /* ACK */

            0x7E7E7E7E7E7E0000, /* BEL */

            0x7E7E7E7E7E7E0000, /* BS */

            0x0, /* TAB */

            0x7E7E7E7E7E7E0000, /* LF */

            0x7E7E7E7E7E7E0000, /* VT */

            0x7E7E7E7E7E7E0000, /* FF */

            0x7E7E7E7E7E7E0000, /* CR */

            0x7E7E7E7E7E7E0000, /* SO */

            0x7E7E7E7E7E7E0000, /* SI */

            0x7E7E7E7E7E7E0000, /* DLE */

            0x7E7E7E7E7E7E0000, /* DC1 */

            0x7E7E7E7E7E7E0000, /* DC2 */

            0x7E7E7E7E7E7E0000, /* DC3 */

            0x7E7E7E7E7E7E0000, /* DC4 */

            0x7E7E7E7E7E7E0000, /* NAK */

            0x7E7E7E7E7E7E0000, /* SYN */

            0x7E7E7E7E7E7E0000, /* ETB */

            0x7E7E7E7E7E7E0000, /* CAN */

            0x7E7E7E7E7E7E0000, /* EM */

            0x7E7E7E7E7E7E0000, /* SUB */

            0x7E7E7E7E7E7E0000, /* ESC */

            0x7E7E7E7E7E7E0000, /* FS */

            0x7E7E7E7E7E7E0000, /* GS */

            0x7E7E7E7E7E7E0000, /* RS */

            0x7E7E7E7E7E7E0000, /* US */

            0x0, /* (space) */

            0x808080800080000, /* ! */

            0x2828000000000000, /* " */

            0x287C287C280000, /* # */

            0x81E281C0A3C0800, /* $ */

            0x6094681629060000, /* % */

            0x1C20201926190000, /* & */

            0x808000000000000, /* ' */

            0x810202010080000, /* ( */

            0x1008040408100000, /* ) */

            0x2A1C3E1C2A000000, /* * */

            0x8083E08080000, /* + */

            0x81000, /* , */

            0x3C00000000, /* - */

            0x80000, /* . */

            0x204081020400000, /* / */

            0x1824424224180000, /* 0 */

            0x8180808081C0000, /* 1 */

            0x3C420418207E0000, /* 2 */

            0x3C420418423C0000, /* 3 */

            0x81828487C080000, /* 4 */

            0x7E407C02423C0000, /* 5 */

            0x3C407C42423C0000, /* 6 */

            0x7E04081020400000, /* 7 */

            0x3C423C42423C0000, /* 8 */

            0x3C42423E023C0000, /* 9 */

            0x80000080000, /* : */

            0x80000081000, /* ; */

            0x6186018060000, /* < */

            0x7E007E000000, /* = */

            0x60180618600000, /* > */

            0x3844041800100000, /* ? */

            0x3C449C945C201C, /* @ */

            0x1818243C42420000, /* A */

            0x7844784444780000, /* B */

            0x3844808044380000, /* C */

            0x7844444444780000, /* D */

            0x7C407840407C0000, /* E */

            0x7C40784040400000, /* F */

            0x3844809C44380000, /* G */

            0x42427E4242420000, /* H */

            0x3E080808083E0000, /* I */

            0x1C04040444380000, /* J */

            0x4448507048440000, /* K */

            0x40404040407E0000, /* L */

            0x4163554941410000, /* M */

            0x4262524A46420000, /* N */

            0x1C222222221C0000, /* O */

            0x7844784040400000, /* P */

            0x1C222222221C0200, /* Q */

            0x7844785048440000, /* R */

            0x1C22100C221C0000, /* S */

            0x7F08080808080000, /* T */

            0x42424242423C0000, /* U */

            0x8142422424180000, /* V */

            0x4141495563410000, /* W */

            0x4224181824420000, /* X */

            0x4122140808080000, /* Y */

            0x7E040810207E0000, /* Z */

            0x3820202020380000, /* [ */

            0x4020100804020000, /* \ */

            0x3808080808380000, /* ] */

            0x1028000000000000, /* ^ */

            0x7E0000, /* _ */

            0x1008000000000000, /* ` */

            0x3C023E463A0000, /* a */

            0x40407C42625C0000, /* b */

            0x1C20201C0000, /* c */

            0x2023E42463A0000, /* d */

            0x3C427E403C0000, /* e */

            0x18103810100000, /* f */

            0x344C44340438, /* g */

            0x2020382424240000, /* h */

            0x800080808080000, /* i */

            0x800180808080870, /* j */

            0x20202428302C0000, /* k */

            0x1010101010180000, /* l */

            0x665A42420000, /* m */

            0x2E3222220000, /* n */

            0x3C42423C0000, /* o */

            0x5C62427C4040, /* p */

            0x3A46423E0202, /* q */

            0x2C3220200000, /* r */

            0x1C201804380000, /* s */

            0x103C1010180000, /* t */

            0x2222261A0000, /* u */

            0x424224180000, /* v */

            0x81815A660000, /* w */

            0x422418660000, /* x */

            0x422214081060, /* y */

            0x3C08103C0000, /* z */

            0x1C103030101C0000, /* { */

            0x808080808080800, /* | */

            0x38080C0C08380000, /* } */

            0x324C000000, /* ~ */

            0x7E7E7E7E7E7E0000 /* DEL */

            };


            星期四, 10月 13, 2022

            Silicon lab matter& low power wifi RS9116

             



            RS9116 

            Standby Associated, DTIM = 10 / 51uA Wi-Fi (1 second beacon listen interval).

            SLEEP_IND_FROM_DEV output pin > to wake up MCU.

            ULP_WAKEUP input pin. > MCU to wake up  RS9116 

            1.      RS9116 auto joining Wifi AP router after power on > Yes.

            Our RS9116 use AT command , MCU can give us SSID and passwords to joining the AP router when power on.    


            星期三, 9月 07, 2022

            星期二, 9月 06, 2022