机型：50L2 机芯T960A1
故障现象：三无
维修与分析：查看打印信息显示，emmc/sd response timeout, cmd8, status=0x3ff2800
emmc/sd response timeout, cmd55, status=0x3ff2800
[mmc_init] mmc init success
Amlogic multi-dtb tool
Single dtb detected
start dts,buffer=0000000033ed4c80,dt_addr=0000000033ed4c80
parts: 12
00: logo 0000000002000000 1
01: rootsys 0000000001800000 1
02: recovery 0000000003000000 1
03: misc 0000000000800000 1
04: impdata 0000000000800000 1
05: userdata 0000000001000000 2
06: tclconfig 0000000002000000 1
07: cache 0000000002000000 1
08: tvos 0000000010000000 1
09: cri_data 0000000001000000 2
10: system 0000000058000000 1
11: data ffffffffffffffff 4
eMMC/TSD partition table have been checked OK!
check pattern success
测量各路电压正常，当时怀疑主芯片通信不良，更换主芯片开机故障还是一样，然后更换EMMC开机故障排除！
