FX Series Programmable Controllers Basic Program Instructions 2
2-13
2.13 MPS, MRD and MPP
Basic points to remember:
- Use these instructions to connect output coils to the left hand side of a contact.
Without these instructions connections can onl
be made to the ri
ht hand side of the
last contact.
- MPS stores the connection point of the ladder circuit so that further coil branches can
recall the value later.
- MRD recalls or reads the previousl
stored connection point data and forces the next
contact to connect to it.
- MPP pops (recalls and removes) the stored connection point. First, it connects the next
contact, then it removes the point from the temporar
stora
e area.
- For ever
MPS instruction there MUST be a correspondin
MPP instruction.
- The last contact or coil circuit must connect to an MPP instruction.
-At an
pro
rammin
step, the number of active MPS-MPP pairs must be no
reater than
11.
Mnemonic Function Format Devices Program steps
MPS
(Point Store)
Stores the current
result of the
internal PLC
operations
N/A 1
MRD
(Read)
Reads the current
result of the
internal PLC
operations
N/A 1
MPP
(PoP)
Pops (recalls and
removes) the
currentl
stored
result
N/A 1
MPS
MRD
MPP
MPS, MRD and MPP usage:
• When writin
a pro
ram in ladder format, pro
rammin
tools automaticall
add all
MPS, MRD and MPP instructions at the pro
ram conversion sta
e. If the
enerated
instruction pro
ram is viewed, the MPS, MRD and MPP instructions are present.
• When writin
a pro
ram in instruction format, it is entirel
down to the user to enter all
relevant MPS, MRD and MPP instructions as required.
