52
IMS01J02-E2
6. RKC COMMUNICATION
6.1 Protocol
RKC communication uses the polling/selecting method to establish a data link. The basic procedure is
followed ANSI X3.28 subcategory 2.5, B1 basic mode data transmission control procedure (Fast
selecting is the selecting method used in SR Mini HG SYSTEM).
•
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 controller 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 SR Mini HG SYSTEM:
EOT (04H), ENQ (05H), ACK (06H), NAK (15H), STX (02H), ETB (17H), ETX (03H)
( ): Hexadecimal
6.1.1 Polling
Polling is the action where the host computer requests one of the connected SR Mini HG SYSTEM to
transmit data. An example of the polling procedure is shown below:
SR Mini HG
SYSTEM
send
SR Mini HG SYSTEM
send
ID: Identifier
Host
computer
send
Host
computer
send
Host computer send
E
O
T
[ Data ]
or
[ BCC ]
[ ID ]
(1)
(2)
(5)
(3)
(4)
(9)
(7)
(10)
[Address] [ ID ]
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
