.../Compare/Fill/Hunt in memory blocks, Use of breakpoints with the BRK instruction, Load/Save/Verify with any storage device.
The cartridge hardware expands upon the firmware features by supplying a de-multiplexer for the $9800..$9FFF I/Ox area (where the firmware is located per default) and a versatile reset button (with autostart inhibit for secondary cartridges).
Size: only 2048 Bytes.
Start with SYS 38912
Read 'instructions.12.txt' for further info.