APPENDIX. HOST COMMUNICATION PROTOCOL
IMR02E20-E1
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A.2 RKC Communication Protocol
RKC communication uses the Polling/Selecting method to establish a data link. The basic procedure is
followed ANSI X3.28-1976 subcategories 2.5 and B1 basic mode data transmission control procedure
(Fast selecting is the selecting method used in SRZ unit).
The Polling/Selecting procedures are a centralized control method where the host computer controls
the entire process. The host computer initiates all communication so the SRZ unit responds
according to queries and commands from the host.
The code use in communication is 7-bit ASCII code including transmission control characters.
Transmission control characters used in SRZ unit:
EOT (04H), ENQ (05H), ACK (06H), NAK (15H), STX (02H), ETB (17H), ETX (03H)
( ): Hexadecimal
A.2.1 Polling procedures
Polling is the action where the host computer requests one of the connected SRZ units to transmit data.
An example of the polling procedure is shown below:
SRZ unit
send
SRZ unit send
ID: Identifier
Host
computer
send
Host
computer
send
[ Data ]
or
[ BCC ]
[ ID ]
(5)
(3)
(4)
(9)
(7)
(10)
Host computer send
No response
No
response
Indefinite
Time
out
(8)
(6)
E
N
Q
E
O
T
E
O
T
S
T
X
E
T
B
E
T
X
E
O
T
A
C
K
N
A
K
E
O
T
(1)
(2)
[Address] [ ] [ ID ]
Memory area number
When polling
the data corresponding
to the memory area
