RT809H е незаменим при ремонт на това шаси. Предполагам, че не си включил външното  му захранване 12V при работа в ISP режим.

Четох и писах в ISP 1.8V режим, като подавах външни 3.3V и 1.8V и замостен кварц. Пробвах същата процедура, за да запиша твоя файл, но не се получи. 

Имах предвид, че без да свържеш RT809H към  външното  захранване 12V , трудно би се свързал с EMMC в това шаси.

Дъмп разбит на части ако ви върши работа
MSTAR: MBOOT   [000000200000 - 000000300000] Size: 3,00 MB
MSTAR: MPOOL   [000000500000 - 000000200000] Size: 2,00 MB
MSTAR: MISC   [000000700000 - 000000080000] Size: 512,00 KB
MSTAR: RECOVERY   [000000780000 - 000001800000] Size: 24,00 MB
MSTAR: BOOT   [000001F80000 - 000000B00000] Size: 11,00 MB
MSTAR: TEE   [000002A80000 - 000000600000] Size: 6,00 MB
MSTAR: RTPM   [000003080000 - 000000040000] Size: 256,00 KB
MSTAR: SYSTEM   [0000030C0000 - 00002BC00000] Size: 700,00 MB
MSTAR: USERDATA   [00002ECC0000 - 000040400000] Size: 1,00 GB
MSTAR: USERSDCARD   [00006F0C0000 - 000100000000] Size: 4,00 GB
MSTAR: CACHE   [00016F0C0000 - 00001EA00000] Size: 490,00 MB
MSTAR: TVSERVICE   [00018DAC0000 - 000009600000] Size: 150,00 MB
MSTAR: TVCONFIG   [0001970C0000 - 000003C00000] Size: 60,00 MB
MSTAR: TVDATABASE   [00019ACC0000 - 000000800000] Size: 8,00 MB
MSTAR: TVCUSTOMER   [00019B4C0000 - 000004200000] Size: 66,00 MB
MSTAR: FACTORY   [00019F6C0000 - 000006400000] Size: 100,00 MB
MSTAR: EMPTY_SPACE   [0001A5AC0000 - 00002C540000] Size: 709,25 MB
Reading Table Completed

Reading Initial Data. Please Wait..

Partition #9 - [SYSTEM] mount as [/dev_8] -> 700,00 MB, Type: EXT4
Partition #10 - [USERDATA] mount as [/data] -> 1,00 GB, Type: EXT4
Partition #11 - [USERSDCARD] mount as [/USERSDCARD] -> 4,00 GB, Type: FAT16
Partition #12 - [CACHE] mount as [/dev_11] -> 490,00 MB, Type: EXT4
Partition #13 - [TVSERVICE] mount as [/dev_12] -> 150,00 MB, Type: EXT4
Partition #14 - [TVCONFIG] mount as [/tvconfig] -> 60,00 MB, Type: EXT4
Partition #15 - [TVDATABASE] mount as [/tvdatabase] -> 8,00 MB, Type: EXT4
Partition #16 - [TVCUSTOMER] mount as [/tvcustomer] -> 66,00 MB, Type: EXT4
Partition #17 - [FACTORY] mount as [/factory] -> 100,00 MB, Type: EXT4

EmptyCheck:
 EMPTY -> ROM_1 -> Part #4 - [MISC]
 EMPTY -> ROM_1 -> Part #18 - [EMPTY_SPACE]
EmptyCheck: Done

Android Info:
Brand           = MStar
Device          = cv6a338_international
Name ID         = aosp_cv6a338_international
Product         = cv6a338_international
Platform        = messi
CPU ABI         = armeabi-v7a
Android Version = 4.4.4
Firm Version    = aosp_cv6a338_international-userdebug 4.4.4 KTU84P 0.0.2 test-keys
Inc. Version    = 0.0.2
Firm Date       = 2018-01-10 20:40:33 +08:00

Scanner Thread Terminated
Elapsed: 00:00:01:993
Found 18 Partition(s)..
Scan Done. Init Main Engine...