Datasensing SH4 BASE-STANDARD, Product Reference Manual, Page: 98 / 103

CASCADE SYSTEM
90
SH4 BASE-STANDARD
RESPONSE TIME
Cascade operation is composed by a serialized optic scanning of all cascade units, then
the same post-Elaboration (optic scan analysis and self-testing) of single unit operation.
Then response time can be calculated in the same way of single unit case considering
Tscan as the time to scan all cascade units (comprehensive of communication messages
for units sync purpose).
T
responceC
=3xT
scanC
+2T
post-elabC
+T
OSSD
Cascade response time can also be computed from single units' response times with fol -
lowing formulas:
2 UNITS CASCADE: Sum of units' response times + 1ms
3 UNITS CASCADE: Sum of units' response times - 1ms
RECOVERY TIME
In cascade operation only receiver master unit synchronize with emitter master unit by
means of two sync optics and respective unique patterns, while T
SCAN
and T
SELF-TEST
depend on all units operation (see fig. 47). For what said in 4.4 recovery time is equal to
response time or 80ms whichever is greater.
SCAN1
ES
WAIT SCAN2
WAIT
WAIT WAIT SCAN3
WAIT
WAIT
PE
M
P
Es
WAIT
WAIT
P
Es
Tcycle
ES
ES
ES
ES
ES
ES
ES
ES
MASTER
SLAVE1
SLAVE2
TresponceC
SCAN1
ES
WAIT SCAN2
WAIT
WAIT WAIT SCAN3
WAIT
WAIT
PE
M
P
Es
WAIT
WAIT
P
Es
ES
ES
ES
ES
ES
ES
ES
ES
SCAN1
ES
WAIT SCAN2
WAIT
WAIT WAIT SCAN3
WAIT
WAIT
PE
M
P
Es
WAIT
WAIT
P
Es
ES
ES
ES
ES
ES
ES
ES
ES
Tcycle Tcycle
T
OSSD