Technical specifications
A.11 S7-200 SMART cables
S7-200 SMART
784
System Manual, V2.3, 07/2017, A5E03822230-AF
A.11.2.3
USB/PPI Multi-Master Cable
To use the USB cable, you must have STEP 7-Micro/WIN SMART V2.3 (or later) installed. It
is recommended that you use the USB cable only with S7-200 SMART CPUs firmware
version V2.3 (or later).
The USB cable does not support Freeport communications.
Note
If you use this cable with S7-200 SMART CPU versions prior to V2.3, certain operations are
not possible (for example, downloading the user program).
Note
Attaching a USB-PPI cable to the CPU's RS485 port forces the CPU to exit Freeport mode
and enable PPI mode. This allows STEP 7-Micro/WIN SMART V2.3 to regain control of the
the CPU.
Table A- 166 USB/PPI Multi-Master cable - Pin-outs for the RS-485 to USB Series "A" Connector
RS-485 Connector Pin-out
USB Connector Pin-out
Pin Number
Signal Description
Pin Number
Signal Description
1
No connect
1
USB -DataP
2
24 V Return (RS-485 logic
ground)
2
USB -DataM
3
Signal B (RxD/TxD+)
3
USB 5 V
4
RTS (TTL level)
4
USB logic ground
5
No connect
-
-
6
No connect
-
-
7
24 V Supply
-
-
8
Signal A (RxD/TxD-)
-
-
9
Protocol select
-
-