Mitsubishi Electric MELSEC-Q Series Programming Manual page 56

Start for a single block
A simultaneous start cannot be made for a single block. The block that has already started cannot be started, either. If either
of the above starts is made, the following processing is performed depending on the setting of the operation mode at block
double START.
■When the setting of the operation mode at block double START is "STOP"
A "BLOCK EXE. ERROR" (error code: 4620) occurs and the CPU module stops processing.
■When the setting of the operation mode at block double START is the default setting of
"WAIT"
Processing is not performed and waits until the START destination block ends its execution.
For the following CPU modules, the operation mode at double block START cannot be set. The operation
mode at double block START is limited to the "WAIT" mode.
• Basic model QCPU
• Q00UJCPU, Q00UCPU, Q01UCPU, Q02UCP
• Universal model QCPU whose serial number (first five digits) is "12051" or earlier
• L02SCPU, L02SCPU-P, L02CPU, L02CPU-P
• LCPU whose serial number (first five digits) is "15101" or earlier
Block START request
A block START request can start multiple blocks simultaneously by performing a parallel transition The steps in the
simultaneously started blocks are processed in parallel.
Number of steps that can be executed simultaneously
The following table indicates the number of steps that can be executed simultaneously and the maximum number of HOLD
steps in a single block.
CPU module type
Basic model QCPU
High Performance model QCPU
Process CPU
Redundant CPU
Universal Q00UJCPU, Q00UCPU, Q01UCPU, Q02UCPU
model QCPU
Q03UDCPU, Q03UDVCPU, Q03UDECPU, Q04UDHCPU,
Q04UDVCPU, Q04UDEHCPU, Q06UDHCPU, Q06UDVCPU,
Q06UDEHCPU, Q10UDHCPU, Q10UDEHCPU, Q13UDHCPU,
Q13UDVCPU, Q13UDEHCPU, Q20UDHCPU, Q20UDEHCPU,
Q26UDHCPU, Q26UDVCPU, Q26UDEHCPU, Q50UDEHCPU,
Q100UDEHCPU
LCPU L02SCPU, L02SCPU-P, L02CPU, L02CPU-P
L06CPU, L06CPU-P, L26CPU, L26CPU-P, L26CPU-BT, L26CPU-
PBT
The execution status of each block can be checked at another block using the block START/END bit or the
block activation check instruction of the SFC control instructions.
4 SFC PROGRAM CONFIGURATION
54
4.2 Steps
Number of steps Maximum number of HOLD steps
that can be in one block
executed
simultaneously
1024 steps 128 steps
1280 steps 256 steps
1024 steps 128 steps
1280 steps 256 steps
1024 steps 128 steps
1280 steps 256 steps