ch341par.exe -w 0xAA Control register bit 0 = STROBE, active low.
First set all control pins high (inactive except INIT which is active high): ch341par.exe
WCH CH341 Download Page (look for CH341PAR utility) ch341par
ch341par.exe -s 0x0D ; low ch341par.exe -s 0x0C ; high -r returns status byte. Busy is bit 7 (value 0x80). Invert logic (busy low = printer busy). low ch341par.exe -s 0x0C
C:\Program Files (x86)\CH341\CH341PAR\ch341par.exe
bcdedit /set testsigning on Then install driver. Reboot. | Tool | Description | |------|-------------| | io.dll + Python | Use pyParallel or pyWin32 with CH341 DLL | | CH341DLL | Programmatic access via C/C++/C# | | GiveIO / UserPort | For legacy LPT ports (not USB) | | libusb + libch341 | Cross-platform (Linux/macOS) |