DVP-ES2-EX2-SS2-SA2-SX2-Operation Manual

2. Programming Concepts
2.14 E, F Index Registers
Index registers are used as modifiers to indicate a specified device (word, double word) by defining
an offset. Devices can be modified includes byte device (KnX, KnY, KnM, KnS, T, C, D) and bit
device (X, Y, M, S). E, F registers cannot be used for modifying constant (K, H) Index registers not
used as a modifier can be used as general purpose register.
Index register [E], [F]
Index registers are 16-bit registers which can be read and written. There are 16 points indicated as
E0~E7 and F0~F7. If you need a 32-bit register, you have to designate E. In this case, F will be
covered up by E and cannot be used. It is recommended to use instruction DMOVP K0 E to reset E
(including F) at power-on.
16-bit
F0
16-bit
E0
32-bit
F0
High word
E0
Low word
The combinations of E and F when designating a 32-bit register are:
(E0, F0) , (E1, F1) (E2, F2) (E3, F3) (E4, F4) , (E5, F5) (E6, F6) (E7, F7)
Example:
When X0 = ON and E0 = 8, F0 = 14, D5E0 = D(5+8) = D13, D10F0 = D(10+14) = D24, the content
in D13 will be moved to D24.
X0
MOV
K8
E0
MOV
K14
F0
MOV
D5E0
D10F0
2.15 Nest Level Pointer[N], Pointer[P], Interrupt Pointer [I]
N Master control nested N0~N7, 8 points
The control point of
master control nested
Pointer
P For CJ, CALL instructions P0~P255, 256 points
The location point of CJ,
CALL
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