Siemens SIMATIC S7 System Manual page 814

Special memory (SM) and system symbol names
D.14 SMB36-SMB45 (HSC0), SMB46-SMB55 (HSC1), SMB56-SM65 (HSC2), SMB136-SMB145 (HSC3),
SMB146-SMB155 (HSC4), SMB156-SMB165 (HSC5): high-speed counters
Table D- 13 HSC4 configuration and operation
S7-200 SMART
symbol name
HSC4_Status
HSC4_Status_5
HSC4_Status_6
HSC4_Status_7
HSC4_Ctrl
HSC4_Reset_Level
HSC4_Rate
HSC4Dir
HSC4_Dir_Update
HSC4_PV_Update
HSC4_CV_Update
HSC4_Enable
HSC4_CV
HSC4_PV
814
SM address Description
SMB146 HSC4 counter status
Note: Counter status bits are valid only while the CPU is executing an inter-
rupt routine that a high-speed counter event triggered.
SM146.0– Reserved
SM146.4
SM146.5 HSC4 current counting direction status bit: TRUE: Counting up
SM146.6 HSC4 current value equals preset value status bit: TRUE: Equal
SM146.7 HSC4 current value is greater than preset value status bit: TRUE: Greater
than
SMB147 HSC4 counter control
SM147.0 HSC4 active level control bit for Reset: FALSE: Reset is active high, TRUE:
Reset is active low
SM147.1 Reserved
SM147.2 HSC4 Counting rate selection for Quadrature counters: FALSE: 4x counting
rate; TRUE: 1x counting rate
SM147.3 HSC4 direction control bit: TRUE: Count up
SM147.4 HSC4 update direction: TRUE: update direction
SM147.5 HSC4 update preset value: TRUE: Write new preset value to HSC4 preset
SM147.6 HSC4 update current value: TRUE: Write new current value to HSC4 cur-
rent
SM147.7 HSC4 enable bit: TRUE: enable
SMD148 HSC4 new current value
You use SMD148 to set HSC4 current value to any value you choose. To
update the current value, write the new current value to SMD148; write 1 to
SM147.6; and execute the HSC instruction. The instruction then writes the
new current value to HSC4's current count register.
SMD152 HSC4 new preset value
You use SMD152 to set HSC4 preset value to any value you choose. To
update the preset value, write the new preset value to SMD152; write 1 to
SM147.5; and execute the HSC instruction. The instruction then writes the
new preset value to HSC4's preset register.
System Manual, V2.3, 07/2017, A5E03822230-AF
S7-200 SMART