@whycan

[00:30:32.641] [19]HELLO! BOOT0 is starting!
[22]BOOT0 commit : 
[24]set pll start
[26]periph0 has been enabled
[28]set pll end
[31][pmu]: bus read error
[33]board init ok
[35]DRAM use external ZQ!!
[38]chip id check OK
[40]POWER SETTING ERROR!
[42]trefi:7.8ms
[45][AUTO DEBUG] single rank and full DQ!
[49]trefi:7.8ms
[51][AUTO DEBUG] rank 0 row = 16 
[55][AUTO DEBUG] rank 0 bank = 8 
[58][AUTO DEBUG] rank 0 page size = 8 KB 
[62]DRAM BOOT DRIVE INFO: V0.16
[65]DRAM CLK = 936 MHz
[67]DRAM Type = 3 (2:DDR2,3:DDR3)
[70]DRAMC ZQ value: 0x7b7bfb
[73]DRAM ODT value: 0x42.
[77]DRAM SIZE =4096 M
[79]dram_tpr4:0x0
[00:30:32.711] [82]DRAM simple test FAIL.
[84]fedcc098 != fedcba98 at address c0000000
[89]init dram fail
[00:30:32.725] C
[00:30:33.225] C
[00:30:33.725] C

V853 空板 usb 升级卡0% ，

两个串口无log