Just select 8810/6820 in miracle box and press format this will reset phone to factory defaults.
Note: Do at your own risk spd based phone are very risky to play with them.
Definition Applied
1. Power Off Phone , Remove Battery, Insert Battery Back
2. Please Hold BootKey(UP and DOWN),Insert USB cable
3. Use Miracle Boot Key In cases Boot key not Find
4. Battery Should be Charged more then 50%
Scanning USB Serial port...
SU2Serial Port: COM29
Connecting to Phone,Wait..
Done.
Infor: SPRD3
Initialize boot13...
CPU type: 8810/6820
Flash type: NAND
Flash ID: 002C00BC
Flash Model: Micron MT29C4G48MAZAPAKD
Flash Size: 0x21000000(528.0M)
Being analyzed,Wait...
Analyzed data OK.(4)
Formating...
>>Format Completed.