Delta DVP-ES2 - Manual (Page 217)

3 . I n s t r u c t i o n S e t
3 - 1 0 1
API Mnemonic Operands Function
39 SFRD P Shift Register Read
Controllers
ES2/EX2 SS2
SA2
SE
SX2
Bit Devices Word devices Program Steps Type
OP X Y M S K H KnX KnY KnM KnS T C D E F
S * * * * * *
D * * * * * * * *
n * *
SFRD, SFRDP: 7 steps
PULSE 16-bit 32-bit
ES2/EX2 SS2
SA2
SE
SX2 ES2/EX2 SS2
SA2
SE
SX2 ES2/EX2 SS2
SA2
SE
SX2
Operands:
S: Head address of data stack D: Destination device n: Length of data stack
Explanation:
1. This instruction defines the data stack of n words starting from S as a FIFO data stack and
specifies the first device as the pointer (S). The content of pointer indicates current length of
the stack. When SFRDP is executed, first data (S+1) will be read out to D, all data in this
stack moves up to fill the read device and content in pointer minuses 1. When the content in
pointer = 0, the instruction stops and carry flag M1022= ON
2. This instruction is generally used in pulse execution mode (SFRDP).
3. Valid range of operand n: 2 ≤ n ≤512
Program Example:
1. When X0 goes from OFF to ON, D9~D2 are all shifted to the right and the pointer D0 is
decremented by 1 when the content of D1 is read and moved to D21.
2. The figure below illustrates the shift and reading of the instruction.
n The content of D1 is read and moved to D21.
o D9~D2 are all shifted to the right.
p The content of D0 is decremented by 1.
D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 D21
X0
SFRDP D0 K10 D21
n = 10 points
Data read
Pointer