Unipulse F701-P, Operation Manual

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9 RS-485 INTERFACE
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5
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Chapter
9
Keep in mind that the relative address for reading the digital zero value is 0x04.
In cases less than 8 bits, the remainder bits become "0".
* The F701-P response (coil state) is always "0" (because processing is executed at the stage of
reading the command).
To confirm coil execution, judge as complete with a normal response to function code 05
(0x05) Force signal coil or 15 (0x0F) Force multiple coils.
02 (0x02) Read discrete inputs
ON/OFF states of slave input statuses are read.
No broadcast can be specified.
Specify the status start address and number of statuses.
* N = Number of statuses/8 or N = N + 1 if indivisible
Example) Read the states from NEAR ZERO (address 10001) to COMPL. (address 10008).
Keep in mind that the relative address for reading the NEAR ZERO value is 0x00.
The example shows the case where the F701-P conditions are as follows:
The LSB of the first data corresponds to the status of the beginning address.
It is expressed as 11110100 (0xF4) in binary notation.
* The statuses can also be read by function code 04 (0x04) Read input registers.
The statuses can be read together with weight values by function code 04.
[Request]
Function 1
byte
0x02
Start address 2
byte
s 0x0000 - 0xFFFF
Number of statuses 2
byte
s 1 - 2000 (0x07D0)
[Response]
Function 1
byte
0x02
Number of data bytes 1
byte
N *
Status state n
byte
s N or N+1
[Error response]
Error code 1
byte
0x82 (fu 0x80)
Exception code 1
byte
01 or 02 or 03
[Request]
Function 02
[Response]
Function 02
Start address; higher 00 Number of data bytes 01
Start address; lower 00 NEAR ZERO - COMPL. F4
Number of statuses; higher 00
Number of statuses; lower 08
NEAR ZERO
OFF
（
0
）
HI
OFF
（
0
）
GO
ON
（
1
）
LO
OFF
（
0
）
SP1
OFF
（
1
）
SP2
OFF
（
1
）
SP3
OFF
（
1
）
COMPL.
ON
（
1
）