hdmi基础培训.ppt

hdmi 其实就是相当于一个同lcd显示相似的接口。 差别在于 热插拔， 兼容性。 能显示有问题，不能显示：和lcd排查方法类似 热插拔： 检查hpd脚状态，hdmi中断脚配置。 1080p显示有问题：检查硬件走线情况 HDMI布线必须换层 电源，rgb信号走线： 影响抖动 换层，阻抗匹配。 参考平面，地平面。esd期间，共模电感，其他信号干扰。反射。 616 HDMI相关几个配置 vif重建：12M重建/lcdc重建 插hdmi后声音的问题。 rk616/618/3188m/3168m由于目前默认使用12m重建，存在的几个小问题： 1. 若使用mipi屏，拔插hdmi瞬间lcd会闪一下。 2. 录音时插拔hdmi会少秒，大概插拔8次左右少1秒. 3. 插hdmi时，只有hdmi有声音，平板上不能输出声音。（其他hdmi默认也是这样，不过若客户有特殊需求者无法修改）。 用dclk重建没有这些问题，不过眼图测试比较临界无法通过（目前还未发现有电视存在兼容性问题），所以若客户提出无法接受以上问题可建议他们改成dclk重建。 cat /sys/kernel/debug/rk616/hdmi rk616_ctl reg 0 1 2 3 4 5 6 7 8 9 a b c d e f ----------------------------------------------------------------- rk616_ctl 0: 75 01 20 81 08 00 22 00 00 00 00 00 00 00 00 00 rk616_ctl 10: 00 00 00 00 00 00 00 00 04 00 06 4d 00 00 02 ca rk616_ctl 20: 04 00 11 df 10 c0 00 54 04 00 00 00 07 6c 02 ee rk616_ctl 30: 00 00 00 00 00 08 40 40 3c 00 0f 00 00 00 00 00 rk616_ctl 40: 18 80 02 84 88 00 00 00 00 00 63 1c 00 00 80 00 rk616_ctl 50: 02 00 02 08 00 06 00 20 00 7f 00 01 89 fe 76 f0 rk616_ctl 60: 00 00 12 26 2c 00 00 00 00 00 00 10 00 00 00 00 rk616_ctl 70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 rk616_ctl 80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 rk616_ctl 90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 08 rk616_ctl a0: 84 01 0a 71 00 00 00 00 00 00 00 00 00 00 00 00 rk616_ctl b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 rk616_ctl c0: 80 00 78 00 00 00 00 00 80 50 70 00 01 00 01 00 rk616_ctl d0: 00 00 00 01 03 09 03 00 ff ff 00 00 d0 20 00 00 rk616_ctl e0: 20 0f aa 0f 02 00 01 96 00 00 00 00 02 0f ----------------------------------------------------------------- cat /sys/kernel/debug/rk616/core 0x0000:0000000000000000 0x0010:00000000000100c1 0x0020: 002c0898 084000c004610029 0x0030:0000000000000000 0x0040:0000000000000000 0x0050:0000001000000002 0x0060:0000004600000641 0x0070:000053de