Delta DVP-10PM, Applications Manual

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5
Categories and Use of Basic Application Instructions
DVP-PM Operation Instruction
5-58
API Mnemonic Operands Function
39 SFRD P Shift Register Read
Controllers
20PM 10PM
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
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 M1970= ON
2. This instruction is generally used in pulse execution mode (SFRDP).
3. When SFRD is used as 16-bit instruction, Z device cannot be adopted; when SFRD is used as 32-bit
instruction, V device cannot be adopted.
4. When specifying the bit device of KnX(Y/M/S), the starting No. should be a multiple of 16 in octal or decimal
format. For example, K1X0, K4Y20 (octal); K1M0, K4S16 (decimal).
5. Valid range of operand
n
: 2 ≤
n
≤ 512
6. Flags:
OX O100
Zero flag M1808 M1968
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