Encounter

Found on:
"Encounter"

Loader files:
ROM Header
Contains only filename
ROM Data
BASIC code which ends with sys call to loader

Encoding:
Endianess:LSbF
Threshold:0x01f4
Lead-in:2064 x '0' bits followed by a single '1' bit
Sync:0xAA+0x55

Structure:
Header:None
Checksum:Yes
Data structure:
Data is arranged in 256 byte blocks. Each block is followed by a one byte checksum.
After the last block there is two additional bytes after the checksum byte.
These are the program start address, low/high order.
The data area seems to have 2047 trailing 0 bits.

Load address start/end is hardcoded. In the ROM Data area the values can be found here.
Load address start low:     0x197
Load address start high:    0x1c8
Load address end high:      0x229

No end low is used.

Checksum:
All bytes added together within each 256 byte block