You can backup PLC data and using it for serial start-up after any fault or after replace RAM-boards. 

DOS-version Step5 v6.6 and etc. is available for winXP, Vista, 7, 8, 8.1, 10 (for x86 and x64) via DosBox.

WINDOWS-version Step5 v7.2 and etc. is available for WinXP x86 only.

All software and "readme" file included on QR-code link.

• dual-port TTY interface fit to all Siemens S5 series PLC (S5-110A/S excluded)
• USB for easy connect to your PC or PG

Suitable old Simatic PLC's:

• All PLC S5 series (S5-110A/S excluded)
• All PLC build-in CNC (System3 and 800 series)

Including:

• interface cable (2m wire. If you need other length, contact me before buy it)
• personal label with software download link via QR-code

ALL INTERFACE CABLE TESTED BEFORE SEND (S5-115U and S5-150U test units)

If you need interface cable for Siemens Sinumerik system, please check my other lot:

Siemens Sinumerik V.24 (COM) dual-port interface cable USB

If you have any question, feel free to contact me.