Mitsubishi MELSEC-A Series Reference Manual page 69

4. COMPOSITION OF A THREE-TIER SYSTEM
(3)
(b) For the CPU module any of the AnUCPU, A2ASCPU(S1), A2USHCPU-S1,
QnACPU, and Q2AS(H)CPU(S1)
Up to two of the following link modules (one as a master station and the other as
a local station) can be used with a CPU module.
(The two modules cannot be used only for master stations or local stations.)
[For local station]
AJ71AP21
AJ71AP21-S3
A1SJ71AP21
AJ71AR21
A1SJ71AR21
[For master station]
AJ71AT21B
A1SJ71AT21B
When using a CPU module with link function as a master station for the third tier
When a CPU module with link function is used with the AJ71AT21B in a three-tier
system, the CPU module can be used as a master station for the third tier and the
AJ71AT21B can be used as a local station in the second tier.
Note that the following AnACPUP21/R21 versions and later can be used as a master
station for the third tier.
When a version earlier than that is used, construction of a three-tier system where
the AJ71AT21B is in the second tier and the CPU module is in the third tier is not
possible.
CPU module with link function
A2ACPUP21
A2ACPUR21
A2ACPUP21-S1
A2ACPUR21-S1
A3ACPUP21
A3ACPUR21
4 - 21
Version
107CX
107BX
107BY
107BY
107CZ
107BZ