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Data Pointer Select Register - usage clarification

Did I understand it right:
ID1 and ID0 in the DPS register change the behaviour of the 8051-“INC DPTR”-instruction to what is given in Table 2.3 “DPTR0, DPTR1 Operations”.
DPS = 0x80
DPTR0 is selected, an “INC DPTR”-instruction will decrement DPTR0,
DPS = 0x81
DPTR1 is selected, an “INC DPTR”-instruction will increment DPTR1.

DPS register is the DPTR0 / DPTR1 selector.
When the INC DPTR instruction is executed, the active DPTR isincremented or decremented according to the ID1, ID0 (DPS.7-6), and SEL (DPS.0) bits as shown.

ID1 | ID0 | SEL | Result of INC DPTR

X | 0 | 0 | Increment DPRT0
X | 1 | 0 | Decrement DPRT0
0 | X | 1 | Increment DPRT1
1 | X | 1 | Decrement DPRT1


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