Siemens Simatic S7 Series System Manual

Program instructions
7.6 Counters
S7-200 SMART
238 System Manual, 09/2015, A5E03822230-AC
Table 7- 7 Status bits for HSC0, HSC1, HSC2, and HSC3
HSC0
HSC1
HSC2
HSC3
Description
SM36.5 SM46.5 SM56.5 SM136.5
Current counting direction status bit:
• 0 = Counting down
• 1 = Counting up
SM36.6 SM46.6 SM56.6 SM136.6
Current value equals preset value status bit:
• 0 = Not equal
• 1 = Equal
SM36.7 SM46.7 SM56.7 SM136.7
Current value greater than preset value status
bit:
• 0 = Less than or equal
• 1 = Greater than
See Also
High-speed counter instructions (Page 220)
Example initialization sequences for the high-speed counters (Page 238)
7.6.5
Example initialization sequences for high-speed counters
HSC0 is used as the counter in the following descriptions of the initialization and operation
sequences.
● HSC0 and HSC2 support counting modes (0, 1), (3, 4), (6, 7), and (9, 10).
● HSC1 and HSC3 only support counting mode 0.
The initialization descriptions assume that the CPU has just been placed in RUN mode, and
for that reason, the first scan memory bit is true. If this is not the case, remember that the
HDEF instruction can be executed only one time for each high-speed counter, after entering
RUN mode. Executing HDEF for a high-speed counter a second time generates a run-time
error and does not change the counter setup from the way it was set up on the first execution
of HDEF for that counter.
Note
Although the following sequences show how to change direction, current value, and preset
value individually, you can change all or any combination of them in the same sequence by
setting the value of SM
B37 appropriately and then executing the HSC instruction.

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.