Melec C-875, Instruction Manual

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4-2. Setting the board identifier port and rotary switch
(1) Board identifier port
This is a port to read out the board number assigned by the rotary switch.
* "1" when active D D D D D D D D ７ ６ ５ ４ ３ ２ １ ０
BIT
Rotary switch ２
０
BIT
Rotary switch ２
１
BIT
Rotary switch ２ ２
BIT Rotary switch ２ ３
Reserved（０）
(2) Setting the rotary switch
C-875 board numbers are assigned by the rotary switch on the board.
If more than two C-875s are used, numbers must be assigned artificially.
Set them by avoiding possible overlaps. When only one C-875 is used, set
the rotary switch to "0". (This setting is made at the time of shipment).
The following sketch shows the example where the board is set to 2.
０
９ １ ２
８
３
７
６ ４
５
4-3. DRIVE COMMAND PORT
Used to write a drive command. For the details of commands, refer to Chapter ６.
4-4. DRIVE DATA1,2,3 PORT (WRITE)
Various data are written by each drive command.
4-5. DRIVE DATA1,2,3 PORT (READ)
Used to read various data.
When reading data by the ADDRESS READ command, SET DATA READ command and ERROR STATUS READ command,
confirm BUSY BIT＝0 in STATUS1 after writing a command.
Reading the count data of the PULSE COUNTER, DIFFERENTIAL COUNTER and ADDRESS COUNTER is always enabled.
4-6. COUNTER COMMAND PORT
Used to write a command to control the PULSE COUNTER and DIFFERENTIAL COUNTER.
For the details of commands, refer to Chapter ９.
4-7. COUNTER DATA1,2,3 PORT (WRITE)
Used to write various data by counter command.