Siemens Simatic S7 Series System Manual

Libraries
9.2 USS library instructions
S7-200 SMART
System Manual, 09/2015, A5E03822230-AC
413
9.2
USS library instructions
9.2.1
USS communication overview
9.2.1.1
USS protocol overview
STEP 7-Micro/WIN SMART instruction libraries make controlling Siemens drives easier by
including pre-configured subroutines and interrupt routines that are specifically designed for
using the USS protocol to communicate with a motor drive. You can control the physical
drive and the read/write drive parameters with the USS instructions.
Siemens designed the USS communications library for use with Siemens general purpose
drives such as the Siemens Micromaster series. Siemens does not intend for the USS
communications library to be used with special purpose drives such as the V90 servo drive.
The control interface of the V90 servo drive is different from that of a general purpose drive.
For this reason, do not use the USS communications library with the V90 servo drive.
You find these instructions in the "Libraries" folder of the STEP 7-Micro/WIN SMART
instruction tree. When you select a USS instruction, one or more associated subroutines and
interrupts are added automatically.
The USS protocol library overview discusses the following subjects:
● Requirements for using the USS protocol (Page 414)
● Calculating the time required for communicating with the drive (Page 415)
Refer to "Using the USS protocol instructions (Page 416)" for a listing of USS protocol
instructions, error codes, and example programs.

Siemens Simatic S7 Series Specifications

General

CPU	Varies by model (e.g., S7-300, S7-400, S7-1200, S7-1500)
Communication Interfaces	PROFIBUS, PROFINET, Ethernet, MPI
Programming	TIA Portal, STEP 7
Programming Languages	LAD, FBD, STL, SCL, GRAPH
I/O Modules	Digital, Analog, Specialty modules available
Operating Temperature	0°C to 60°C (standard models)
Mounting	DIN rail mounting
Operating Voltage	24V DC or 120/230V AC (varies by model)
Protection Class	IP20 (standard models)
Memory	Varies depending on the S7 model. Includes work memory (RAM) for program execution, load memory (EEPROM or Flash) for program storage, and system memory for operating system functions. Memory sizes range from kilobytes to megabytes.