Z80Stealth v1.23 is released. Z80Stealth is a Spectrum emulator for DOS that also works in Win98. It emulates the Spectrum 128. It's an excelent emulator, and is worth a try.

Z80Stealth v1.23 Changelog:
Added secondary TRDOS autoboot, key mapping is set in keyboard.cfg,TRDOSBOOT2 (default – PGDOWN)
Partially rewrote Z80 engine, small bugfixes
Added memory/ports logging, with detailed info about addresses, opcodes, memory type (data/code)
Activate in menu Tools->Ports(Mem) log start/stop
Output files:
_Memlog_.txt memory access log
_Memlog_layout_.txt memory type log
_portlog_.txt port access log
Also you can log masked potrs, define them in z80s.ini in [DEBUG] section, example:
MASKEDPORTSCOUNT=2
MASKEDPORT.1=11111101
MASKEDPORT.2=xxxxxxx1

Download: Z80Stealth v1.23
Source: Here