@george fc2f87b3-499a-4776-870a-a2561f6f19d9-image.png

原因找到了，是configuration 那里要设置选择HFP

@allen 内核打开binder IPC

@macthree 建议全新安装会更好，0303版本是纯净版系统，您也可以下载我们github ubuntu仓库构建纯净版本镜像

补充内核编译操作说明（如下以coolpi 4b ubuntu22.04 0306系统版本为例）：

首先下载内核源码

coolpi@coolpi:~$ git clone https://github.com/yanyitech/coolpi-kernel.git Cloning into 'coolpi-kernel'... remote: Enumerating objects: 8550563, done. remote: Counting objects: 100% (5962/5962), done. remote: Compressing objects: 100% (3084/3084), done. remote: Total 8550563 (delta 2757), reused 5819 (delta 2648), pack-reused 8544601 Receiving objects: 100% (8550563/8550563), 1.98 GiB | 11.07 MiB/s, done. Resolving deltas: 100% (7166058/7166058), done. Checking objects: 100% (33554432/33554432), done. Updating files: 100% (87196/87196), done. coolpi@coolpi:~$

额外安装组件包

coolpi@coolpi:~$ sudo apt install -y flex bison libssl-dev coolpi@coolpi:~$ sudo ln -sf /usr/bin/python3 /usr/bin/python

开始编译内核

coolpi@coolpi:~$ cd coolpi-kernel coolpi@coolpi:~/coolpi-kernel$ ./build-kernel.sh cp4b

@jack_admin I mean can output video signal on the gpio using with custom timings, like you can on the RPI4?

@test 你的loader版本看起来比较早，升级loader试下。卡的分区表异常，格式化一次

@jack_admin 已经成功

@jack_admin 那就没有问题了，只要优先从tf卡启动就行，我已经通过tf卡启动ubuntu22.04，然后通过dd命令将img写入到emmc中，并且启动成功。这样就再也不用把emmc从板子上取下来了，yeah！谢谢

@xingzhan2012 可以用cool pi ubuntu系统，直接dd 刷系统到其他存储介质，比如emmc

latest loader image files

百度网盘下载cool pi 4b loader在线刷机包

OneDrive download cool pi 4b loader

@reddfoxx Refer to attachment link：
https://www.aliexpress.us/item/3256803830903295.html?spm=a2g0o.productlist.main.51.2d623ca45F44fO&algo_pvid=370776b3-bc3a-44b3-b469-07b7abd5eb71&algo_exp_id=370776b3-bc3a-44b3-b469-07b7abd5eb71-25&pdp_ext_f={"sku_id"%3A"12000027750691599"}&pdp_npi=2%40dis!USD!0.17!0.13!!!!!%40212244c416739165017785791d0685!12000027750691599!sea&curPageLogUid=LiqQEObfPtMi

coolpi/coolpi is the username and password for the debian build. people need to do a better job of documenting on this forum.