Siemens SIMATIC S7 System Manual page 24

Product overview
1.3 CPU feature differences
USB-PPI cable
The CRs models provide the RS485 port as the only programming port for the CPU. Using
STEP 7-Micro/WIN SMART and a USB-PPI cable, you can perform the following tasks:
● Upload and download your program
● Monitor program functions
● Perform firmware updates
If you use Freeport (Page 465) in your program, attaching a USB-PPI cable forces the CPU
to exit Freeport mode and enables PPI mode. PPI mode allows STEP 7-Micro/WIN SMART
to regain control of the CPU.
Communication connections
Since the CRs CPU models support only an RS485 programming port, the CPU always
reserves one connection for the STEP 7-Micro/WIN SMART programmer connection. The
CRs model CPUs still support four connections on the RS485 port for HMIs.
No CPU instructions that require an Ethernet port
You cannot use the CPU instructions that utilize the Ethernet port on the CRs models. The
instructions that are not available in the CRs models are as follows:
LAD instruction
GET
SET
GIP_ADDR
SIP_ADDR
TCON
TSEND
TRECV
TDCON
No real-time clock
The CRs models do not have a real-time clock; however, the CRs models still support time
instructions. The time resets to the default time (January 1, 2000) on every power cycle. The
CPU maintains time with limited accuracy without the real-time clock.
No microSD card reader or any functions related to the use of a microSD card
Because the CRs models do not support a microSD card, you use the Reset to factory
defaults command (Page 164) using the RS485 port in case you forget your password.
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STL instruction
GET
SET
GIP
SIP
TCON
TSEND
TRECV
TDCON
Description
Get data through the Ethernet
Write data through the Ethernet
Get Ethernet IP address
Set Ethernet IP address
Open an OUC Ethernet connection
Send OUC data through the Ethernet
Receive OUC data through the Ether-
net
Disconnect an OUC Ethernet connec-
tion
System Manual, V2.3, 07/2017, A5E03822230-AF
S7-200 SMART