- Added magic numbers to pretend the NEC original program version
2.70.
- Added string display routine with Shift-JIS code support.
- Added three nop instructions at start1 in start.s since the
installaer of the IPLware put 'call $0x09ab' instruction.
- Put the near return instruction at 0x9ab in selector.s.
Since the Shit-JIS display routine must be located at 0x1243, the
linker script file (ldscript) is applied.