APPENDIX. HOST COMMUNICATION PROTOCOL
IMR02E20-E1
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(1) Data link initialization
Host computer sends EOT to the controllers to initiate data link before polling sequence.
(2) Data sent from host computer - Polling sequence
The host computer sends the polling sequence in the following two types of formats:
Format in which no memory area number is specified, and
Format in which the memory area number is specified.
When no memory area number is specified
To be sent in this format for any identifier not corresponding to the memory area.
When the memory area number is specified
To be sent in this format for any identifier corresponding to the memory area.
1.
Address (2 digits)
This data is a host communication address of the COM-ML for polled and must be the same as
the unit address set value in item
5.1 Address Setting (P. 21)
.
The polling address which transmitted a message once becomes effective so long as data
link is not initialized by transmit and receive of EOT.
2.
Memory area number (2 digits)
This is the identifier to specify the memory area number. It is expressed by “K1” to “K8” to each
memory area number (from 1 to 8). If the memory area number is assigned with “K0,” this
represents that control area is specified.
The memory area now used for control is called “Control area.”
If the memory area number is not specified when polling the identifier corresponding to
the memory area, this represents that the control area is specified.
If any identifier not corresponding to the memory area is assigned with a memory area
number, this memory area number is ignored.
Identifier
Address
Example:
ENQ
1
M
0
1
4.
3.
1.
ENQ
4.
3.
2.
1.
Memory
area
number
Identifier
Address
ENQ
K
Example:
ENQ
S
1
1
K
0
1
